Flange Hard Seal Butterfly Valve | DN50-1800 Triple Offset Factory

A Flange Hard Seal Butterfly Valve is a triple-offset (three-eccentric) metal hard-seal flanged butterfly valve with flexible actuation options (manual handwheel, bevel gear, electric actuator, or pneumatic actuator) that rotates a triple-offset metal-sealed disc 90° for on-off or flow regulation in high-temperature, high-pressure, corrosive, and cryogenic severe-service pipelines - adopting a triple-eccentric structure with multi-layer metal hard seal (stainless steel + hard alloy overlay, or Cr13 series + graphite interlayer) achieving ANSI/FCI 70-2 Class IV leakage (Class V optional for high-precision), friction-free opening/closing (no contact between disc and seat during rotation), DN50-1800 (2"-72"), PN10-40 (high-pressure type PN64/Class 400), -29~425°C (high-temp to 600°C, cryogenic to -196°C for LNG), flanged RF/RTJ connection (ANSI B16.5/DIN/JIS/GB), full-bore low flow resistance, WCB/SS304/316/316L/WC6/WC9/ductile iron/duplex/LCB body, for petrochemical, power, metallurgy, water treatment, LNG - a reliable triple-offset hard-seal flanged butterfly valve with flexible actuation for severe high-temp/high-pressure/cryogenic pipelines. The core highlights are: (a) Triple-offset (three-eccentric) hard-seal structure (core): (i) three eccentricities - stem axis offset + seat axis offset + inclined cone angle; (ii) friction-free - disc completely disengages from seat during 0-90° rotation (no rubbing/wear); (iii) self-energizing - cam/wedge action at closing, tighter with pressure; (iv) bidirectional - seals both directions; (v) long seal life - 3-5× ordinary butterfly; (b) Multi-layer metal hard seal: (i) stainless steel + hard alloy overlay (Stellite/Co-Cr, HRC≥40) - wear/heat/corrosion; (ii) Cr13 series + graphite interlayer - metal hardness + graphite lubrication/elasticity; (iii) "dual advantages of hard seal and soft seal" - metal for high temp/wear, graphite for compliance/zero-ish leak; (iv) ANSI/FCI 70-2 Class IV (low leakage), Class V optional (high-precision, near zero); (v) no rubber/PTFE (for high temp >425°C); (c) Flexible actuation (manual/gear/electric/pneumatic): (i) manual handwheel - simple, no power, for small DN; (ii) bevel gear - labor-saving (50-80% effort reduction), self-locking, for large DN; (iii) electric - remote/automated, 4-20mA regulation, DCS/PLC; (iv) pneumatic - fast (1-3s), fail-safe (spring-return), for ESD; (v) one valve body, multiple actuator options - customer chooses per automation level; (d) Large bore DN50-1800: (i) standard DN50-1800 (2"-72") - covers most industrial needs; (ii) large DN uses reinforced disc/truss, high-torque actuator or gearbox; (e) Medium-high pressure PN10-40 (PN64 HP): (i) standard PN10/16/25/40 (Class 150-300); (ii) high-pressure type to PN64 (Class 400) - reinforced body, robust flange; (iii) for steam, oil, gas, high-pressure process; (f) Wide temperature -196~600°C: (i) standard -29~425°C (carbon/alloy body); (ii) high-temp type to 600°C (alloy/stainless + metal seal); (iii) cryogenic type to -196°C (LCB/LCC/304L/316L + extended bonnet, for LNG/LOX/LIN); (iv) one of the widest temp ranges in butterfly series; (g) Flanged RF/RTJ connection: (i) raised face (RF) for general; (ii) ring-type joint (RTJ) for high-pressure/high-temp (Class 400+, PN64); (iii) standards ANSI B16.5, DIN, JIS, GB/T 9115; (iv) robust, easy install/removal, load-bearing (vs wafer); (h) Full-bore low flow resistance: (i) disc fully retracts when open - nearly unobstructed flow path; (ii) low K factor (~0.3-0.5), minimal pressure loss; (iii) energy-saving for large pipelines; (i) Materials: (i) body: WCB carbon, SS304/316/316L, WC6/WC9 alloy (high-temp), ductile iron, duplex (corrosion), LCB/LCC (cryogenic); (ii) disc: stainless, cast iron, duplex, nickel aluminum bronze (NAB - seawater/wear), PTFE lined (corrosion); (iii) stem: CF8/CF8M/SS304/316, anti-blowout; (j) Standards: design API 609, BS EN 593, MSS SP-67, GB/T 13927; test API 598, API 6D; (k) Applications: petrochemical (crude oil, natural gas, chemical reagents), power (boiler, steam, circulating water), metallurgy (blast furnace, steelmaking, high-temp flue gas), water treatment (sewage, water supply, desalination), LNG/cryogenic; (l) Cost-effective: flexible actuation = choose only what you need (manual cheapest, pneumatic for fast/fail-safe, electric for automation); (m) Versatile: one platform covers manual to automated, small to large, general to cryogenic. This is the reliable triple-offset hard-seal flanged butterfly valve with flexible actuation for severe high-temp/high-pressure/cryogenic pipelines.

The triple-offset friction-free metal hard seal (Class IV/V), flexible actuation (manual/gear/electric/pneumatic), flanged robust connection, large bore DN50-1800, medium-high pressure (PN64 HP), wide temperature (-196~600°C including cryogenic LNG), and full-bore low flow resistance make this valve a versatile severe-service triple-offset hard-seal flanged butterfly valve - distinct from pneumatic-only, electric-only, wafer, soft-seal, or ventilation butterfly valves - designed for high-temperature, high-pressure, corrosive, and cryogenic industrial pipelines where flexible actuation choice, robust flanged connection, metal hard seal for high temp/abrasion, and large bore are priorities. Compared to other butterfly valves: (a) vs Pneumatic Flange Hard Seal (eleventh): that one is pneumatic-only + DN50-1200 (custom DN4000) + PN100 HP + fast 1-3s + fail-safe; this one is manual/gear/electric/pneumatic (all options) + DN50-1800 + PN64 HP + full-bore - flexible multi-actuation large-bore vs pneumatic-only ultra-large/ultra-high-pressure (both triple-offset hard seal flanged, but this = all actuators + DN1800 + PN64; that = pneumatic only + DN4000 custom + PN100 + fast/fail-safe); (b) vs Electric Double-clamped Hard Seal (tenth): that one is electric + double-clamped wafer + DN50-400 + PN1.6-42 (ultra-high) + explosion-proof + regulation; this one is manual/gear/electric/pneumatic + flanged RF/RTJ + DN50-1800 + PN10-40 (PN64 HP) + -196~600°C (cryogenic) - flanged multi-actuation large-bore wide-temp vs electric double-clamped ultra-high-pressure; (c) vs Extended Flange Hard Seal (third): that one is triple-offset metal hard seal + extended flange (expansion joint) + DN50-2000 + high temp 650°C + PN0.6-2.5 (low pressure); this one is triple-offset metal hard seal + standard flange (no expansion) + DN50-1800 + PN10-40 (PN64 HP) + multi-actuation + cryogenic - multi-actuation high-pressure standard-flange vs manual low-pressure expansion-flange; (d) vs Electric Flange Butterfly Valve (first): that one is electric + flanged + soft/hard seal (general) + DN50-2000 + PN1.0-6.4; this one is manual/gear/electric/pneumatic + triple-offset metal hard seal + DN50-1800 + PN10-40 (PN64) + -196~600°C - multi-actuation severe-service metal-seal vs electric general soft/hard-seal; (e) vs Pneumatic Wafer (eighth): that one is pneumatic + wafer (clamp-on) + soft/hard seal + DN50-1200 + PN10-40 + fast 0.5-2s + fail-safe; this one is manual/gear/electric/pneumatic + flanged RF/RTJ + triple-offset metal hard seal (Class IV/V) + DN50-1800 + PN64 HP + -196~600°C (cryogenic) - flanged multi-actuation metal hard-seal high-pressure/cryogenic vs wafer pneumatic general soft/hard-seal; (f) vs Fire Signal (second): that one is fire-protection signal + soft seal + DN50-400 + fire water; this one is multi-actuation + triple-offset metal hard seal + high-pressure + high-temp/cryogenic + industrial severe - completely different; (g) vs Stainless Steel Handled Clamp-on (fourth): that one is all-stainless + lever + wafer + soft seal + sanitary + small; this one is WCB/alloy/SS + multi-actuation + flanged + metal hard seal + large bore + severe - completely different; (h) vs Worm Gear Flange (fifth): that one is worm gear manual + flanged + soft/hard seal + DN50-2200 + general; this one is manual/gear/electric/pneumatic + triple-offset metal hard seal + DN50-1800 + PN64 + cryogenic - multi-actuation severe vs manual large-bore general; (i) vs Stainless Steel PTFE Wafer (sixth): that one is all-stainless + PTFE soft seal + wafer + DN40-350 + chemical; this one is WCB/alloy/SS + metal hard seal + flanged + DN50-1800 + high-temp/cryogenic - metal hard-seal high-temp vs PTFE soft-seal chemical; (j) vs Flange Telescopic (seventh): that one is butterfly + telescopic expansion joint 2-in-1 + flanged + DN32-3200 + water; this one is standard triple-offset + flanged + multi-actuation + DN50-1800 + high-pressure/cryogenic - completely different; (k) vs Flange Ventilation (ninth): that one is ventilation non-hermetic (≤1% leak) + large bore + 900°C + low pressure + gas/dust; this one is sealing Class IV/V + DN50-1800 + 600°C + PN64 + liquid/gas severe - sealing high-pressure vs non-sealing ventilation; (l) vs general flanged butterfly: general = soft seal, medium pressure; this = triple-offset metal hard seal, high pressure, cryogenic. Triple-offset + metal hard seal principle (same as pneumatic flanged / electric double-clamped, but multi-actuation): (a) three offsets = friction-free rotation + self-energizing + bidirectional; (b) multi-layer metal seal: (i) stainless + hard alloy overlay (Stellite) - hard, wear/heat; (ii) Cr13 + graphite interlayer - Cr13 (13Cr stainless, hard) + graphite (soft, lubricating, compliant) - "metal + soft" composite; (iii) Class IV (standard, low leakage ~0.01% for metal seal); (iv) Class V optional (higher precision, near zero - for hazardous/steam); (c) no rubber (for >425°C); graphite can handle high temp. Flexible actuation principle: (a) manual handwheel: (i) direct stem rotation via handwheel; (ii) simple, no power, low cost; (iii) for DN≤150 (small, low torque); (b) bevel gear: (i) handwheel → bevel gear → stem (mechanical advantage 50-80% effort reduction); (ii) self-locking (worm gear holds position, no drift); (iii) for DN200-1800 (large, high torque); (c) electric: (i) multi-turn or quarter-turn electric actuator (AC220/380V/DC24V); (ii) on-off or 4-20mA regulation; (iii) remote/DCS/PLC, signal feedback; (iv) for automated lines; (d) pneumatic: (i) rack-pinion actuator (double-acting or single-acting spring-return); (ii) fast 1-3s, fail-safe FC/FO; (iii) for ESD/hazardous; (e) ISO 5211 mounting pad - all actuators mount via standard pad (interchangeable). Flanged RF/RTJ principle: (a) RF (raised face) - standard, gasket (spiral wound graphite) on raised face; (b) RTJ (ring-type joint) - for high-pressure/high-temp (Class 400+, PN64), metal ring (octagonal/oval) fits into grooves on flange faces - metal-to-metal seal, very high pressure; (c) flanged = robust (integral flange, load-bearing, easy one-side removal, high pressure capable); (d) standards ANSI B16.5 (≤DN600), B16.47 (large), DIN, JIS, GB. Full-bore low flow resistance: (a) when open (0°), disc parallel to flow, fully retracted into body cavity; (b) nearly unobstructed flow path (disc thickness is only obstruction); (c) low K factor (~0.3-0.5), much lower than globe/gate valve; (d) energy-saving (less pumping power), especially for large DN/high flow. Wide temperature including cryogenic: (a) standard -29~425°C (WCB/alloy + metal seal); (b) high-temp to 600°C (WC6/WC9 alloy / SS310S + metal seal, extended bonnet); (c) cryogenic to -196°C (LCB/LCC low-temp carbon / 304L/316L austenitic stainless + extended long-neck bonnet (keeps packing above frost point) + cryogenic-treated parts, for LNG/LOX/LIN/LAR); (d) one of few butterfly valves covering both high temp (600°C) and cryogenic (-196°C). High-pressure type PN64 (Class 400): (a) reinforced body (thick wall), RTJ flange, high-strength bolts, robust stem/seat; (b) typically DN≤400-600 (larger at PN64 = heavy/custom); (c) for high-pressure steam/oil/gas. Testing: (1) body hydrostatic 1.5×PN; (2) seat leak 1.1×PN - Class IV (or Class V if specified); (3) operation (per actuator - manual/gear/electric/pneumatic, 0-90°); (4) cryogenic test (if cryogenic type - LN2 seal+operation); (5) NDT (body for high pressure/alloy); (6) PMI (stainless/alloy); (7) flange dimension; (8) fire-safe (optional API 607 - metal seal). Maintenance: (1) periodic exercise; (2) inspect leaks; (3) seat (metal - inspect annually, re-lap if Class IV/V degraded); (4) actuator maintenance per type (manual: lubricate gear; electric: check motor/wiring; pneumatic: FRL, solenoid, air lines, spring); (5) cryogenic type - extended bonnet, no ice on stem; (6) flange bolts re-torque. Important: (a) Class IV = low leakage, NOT zero (if zero leakage needed, specify Class V or soft-seal valve); (b) PN64 high-pressure = size limit, RTJ flange, confirm; (c) cryogenic -196°C = special body/bonnet/parts, extended bonnet, cryogenic test; (d) flanged = load-bearing (but still support large pipe); (e) actuator choice - specify manual/gear/electric/pneumatic at order (we size per DN/PN); (f) not for heavy abrasive slurry (metal seal scratches - use knife gate; small particles OK); (g) warranty: 18 months (valve), 12 months (electric/pneumatic actuator). The valve is manufactured under strict quality control with 100% hydrostatic, 100% seat leak (Class IV/V), 100% operation test, material cert, API 609/BS EN 593/MSS SP-67, API 598/API 6D. With an 18-month warranty (valve) / 12-month (actuator) and OEM/ODM customization (actuator type, size, high-pressure PN64, cryogenic -196°C, material, seal Class V), this valve is a reliable triple-offset hard-seal flanged butterfly valve with flexible actuation for severe high-temp/high-pressure/cryogenic pipelines.

1.Triple-Offset Friction-Free + Metal Hard Seal Class IV/V

Three-eccentric (triple-offset) structure - disc completely disengages from seat during 0-90° rotation (zero friction/wear), self-energizing cam/wedge bidirectional seal. Multi-layer metal hard seal: stainless steel + hard alloy (Stellite) overlay, or Cr13 series + graphite interlayer - combines metal hardness (heat/wear) with graphite compliance. ANSI/FCI 70-2 Class IV leakage (Class V optional for high-precision/hazardous). Seal life 3-5× ordinary butterfly. Fire-safe (API 607 optional).

2.Flexible Actuation - Manual/Gear/Electric/Pneumatic

One valve body supports four actuation options via ISO 5211 standard mounting pad: manual handwheel (simple, no power, small DN), bevel gear (labor-saving 50-80%, self-locking, large DN), electric (remote/automated, 4-20mA regulation, DCS/PLC), pneumatic (fast 1-3s, spring-return fail-safe FC/FO for ESD). Customer chooses per automation level - no need to change valve body. Interchangeable actuators for future upgrade.

3.Large Bore DN50-1800 + Medium-High Pressure

Standard DN50-DN1800 (2"-72") - covers most industrial needs from small process lines to large mains. Pressure PN10/16/25/40 (Class 150-300) standard; high-pressure type up to PN64 (Class 400) with reinforced body and RTJ flange. Full-bore design with low flow resistance (K~0.3-0.5) - energy-saving for large pipelines. Flanged RF/RTJ (ANSI B16.5/DIN/JIS/GB) - robust, load-bearing, easy install.

4.Wide Temperature -196°C to 600°C (Including Cryogenic)

Standard -29°C~425°C (carbon/alloy body + metal seal); high-temperature type up to 600°C (WC6/WC9 alloy / stainless + metal seal, extended bonnet); cryogenic type down to -196°C (LCB/LCC/304L/316L + extended long-neck bonnet, cryogenic-treated parts, for LNG/LOX/LIN/LAR). One of the widest temperature ranges in butterfly valve series - handles both extreme high temp and cryogenic service.

5.Durable Corrosion-Resistant Materials + Full-Bore

Body: carbon steel (WCB), stainless steel (304/316/316L), alloy steel (WC6/WC9 high-temp), ductile iron, duplex steel (corrosion), LCB/LCC low-temp carbon (cryogenic). Disc: stainless, cast iron, duplex, nickel aluminum bronze (NAB - seawater/wear), PTFE lined (corrosion). Stem: CF8/CF8M/SS304/316 anti-blowout. Full-bore when open - disc fully retracts, nearly unobstructed flow, minimal pressure loss. Handles steam, hot oil, gas, corrosive chemicals, seawater, cryogenic LNG.

6.Standards + Quality + Warranty + Versatile

Design: API 609, BS EN 593, MSS SP-67, GB/T 13927; test: API 598, API 6D. 100% body hydrostatic (1.5×PN), 100% seat leak (Class IV/V), 100% operation test (per actuator), cryogenic test (if cryogenic type), NDT (high pressure/alloy), PMI (stainless/alloy). For petrochemical, power, metallurgy, water treatment, LNG. 18-month warranty (valve), 12-month (electric/pneumatic actuator), OEM/ODM (actuator type, size, PN64, cryogenic, Class V).

A Flange Hard Seal Butterfly Valve operates on the principle of a quarter-turn rotating triple-offset (three-eccentric) metal-sealed disc with flexible actuation (manual/gear/electric/pneumatic) in a flanged (RF/RTJ) body - the actuator (manual handwheel, bevel gear, electric motor, or pneumatic cylinder) converts input force/torque into rotational torque, rotating the stem and triple-offset disc 90°; the three eccentricities ensure the disc sealing surface completely disengages from the seat during most of the rotation (friction-free, no wear), and only at the final closing does the disc cam/wedge into the multi-layer metal seat to form a bidirectional Class IV (or Class V) metal-to-metal seal; when open (0°), disc is parallel to flow (low resistance, full-bore); the multi-layer metal seal (stainless + hard alloy overlay, or Cr13 + graphite interlayer) handles high temp (600°C) and abrasion; with DN50-1800, PN10-40 (PN64 HP), -196~600°C, flanged RF/RTJ connection, flexible actuation, full-bore low flow resistance - a reliable severe-service triple-offset hard-seal flanged butterfly valve with flexible actuation for high-temp/high-pressure/cryogenic pipelines. The valve consists of a flanged body (WCB/SS/alloy/ductile/duplex/LCB, with integral RF/RTJ flanges), a triple-offset disc (stainless/CI/duplex/NAB/PTFE, with metal hard seal surface), a stem (CF8/CF8M/SS, anti-blowout), a multi-layer metal seat (stainless + hard alloy overlay, or Cr13 + graphite interlayer), packing (flexible graphite, extended bonnet for cryogenic/high-temp), and an actuator (manual handwheel, bevel gear, electric, or pneumatic - mounted via ISO 5211 bracket/coupling). Triple-offset (three-eccentric) principle - core: (same as pneumatic flanged / electric double-clamped hard seal) (a) First offset - stem axis offset: stem rotational axis offset from seat/body centerline - disc swings away from seat on opening; (b) Second offset - seat axis offset: seat cone axis offset from body center - further disengagement; (c) Third offset - cone angle inclination: seat sealing surface is inclined cone - cam/wedge action at closing, self-energizing; (d) Result: friction-free rotation (zero contact for ~80-90° stroke), self-energizing seal (tighter with pressure), bidirectional sealing, low torque, long seal life (3-5× ordinary). Multi-layer metal hard seal principle: (a) Type 1 - stainless + hard alloy overlay: (i) seat/disc base = stainless steel; (ii) sealing surface overlay-welded with cobalt-based Stellite (Co-Cr-W) or other hard alloy (HRC≥40); (iii) precision ground + lapped; (iv) hard, wear/heat/corrosion resistant; (b) Type 2 - Cr13 + graphite interlayer: (i) Cr13 (13Cr stainless, e.g., 410/420) - hard, wear-resistant; (ii) graphite interlayer - soft, compliant, lubricating, heat-resistant (to 600°C+); (iii) "metal + soft graphite" composite - metal provides strength/wear, graphite provides compliance/seal; (iv) "dual advantages of hard seal and soft seal"; (c) Leakage class: (i) Class IV (standard) - low leakage (per ANSI/FCI 70-2, ~0.01% for metal seal, not zero); (ii) Class V optional - higher precision (near zero, for hazardous/steam - tighter lapping, better compliance); (d) No rubber/PTFE - for high temp >425°C (rubber/PTFE would fail); graphite handles high temp; (e) Fire-safe - all-metal (or metal+graphite) = inherently fire-safe (API 607 optional). Flexible actuation principle: (a) Manual handwheel: (i) handwheel directly coupled to stem (via yoke); (ii) operator rotates handwheel → stem/disc rotates 90°; (iii) simple, no power, low cost, reliable; (iv) for DN≤150 (small, low torque - operator can handle); (v) visual position (handwheel orientation); (b) Bevel gear: (i) handwheel → bevel gear set (worm gear or spiral bevel) → stem; (ii) mechanical advantage - reduces operator effort 50-80% (gear ratio); (iii) self-locking (worm gear holds position, no drift under pressure/vibration); (iv) for DN200-1800 (large, high torque); (v) handwheel position indicator; (c) Electric actuator: (i) multi-turn or quarter-turn electric motor (AC220/380V/DC24V) → gear reduction → stem; (ii) on-off type - open/close, limit switches, torque protection; (iii) regulation type - 4-20mA positioner, precise flow control, position feedback; (iv) remote/DCS/PLC, signal feedback (4-20mA or NO/NC); (v) manual emergency handwheel override (power loss); (vi) for automated lines, remote control; (d) Pneumatic actuator: (i) rack-pinion piston actuator (double-acting or single-acting spring-return); (ii) double-acting - air open/air close, fast 1-3s; (iii) single-acting - spring-return fail-safe FC/FO (for ESD); (iv) air 0.4-0.7MPa; (v) accessories: solenoid, limit switch, FRL, positioner (4-20mA); (e) ISO 5211 mounting pad - all actuators mount via standard pad + coupling (interchangeable - customer can upgrade from manual to electric/pneumatic later); (f) actuator sizing - per valve torque (DN×PN×pressure), we size and supply. Flanged RF/RTJ connection principle: (a) RF (Raised Face): (i) flange face has raised ring; (ii) gasket (spiral wound graphite, PTFE, rubber) on raised face; (iii) bolts compress gasket → seal; (iv) for general/medium pressure (Class 150-300, PN10-40); (b) RTJ (Ring Type Joint): (i) flange faces have grooves (octagonal/oval); (ii) metal ring (soft iron, low-carbon steel, Monel) sits in grooves; (iii) bolts compress ring → ring deforms into grooves → metal-to-metal seal; (iv) for high-pressure/high-temp (Class 400+, PN64, >400°C); (v) very high pressure capability, no gasket blowout; (c) Flanged advantages: robust (integral flange, load-bearing), easy one-side removal (vs wafer), high pressure capable, standard gasket/ring; (d) Standards: ANSI B16.5 (≤DN600), ASME B16.47 (DN>600), DIN, JIS, GB/T 9115. Full-bore low flow resistance: (a) when open (0°), disc is parallel to flow, fully retracted into body cavity (above/below flow path); (b) only disc thickness (and stem) obstructs flow - nearly unobstructed; (c) K factor ~0.3-0.5 (much lower than globe valve K~5-10, gate valve K~0.1-0.3); (d) minimal pressure loss, energy-saving (less pumping/compression power); (e) especially beneficial for large DN/high-flow pipelines (water mains, gas mains, flue gas). Wide temperature including cryogenic: (a) standard -29~425°C: WCB carbon + WC6/WC9 alloy + metal seal; (b) high-temp to 600°C: (i) body WC6/WC9 (Cr-Mo alloy) or SS310S/2520; (ii) metal seal (Stellite/graphite); (iii) extended bonnet (keeps packing away from high temp); (iv) high-temp bolts/gaskets; (c) cryogenic to -196°C: (i) body LCB/LCC (low-temp carbon steel) or 304L/316L (austenitic stainless, low carbon - prevents brittle fracture); (ii) extended long-neck (cryogenic) bonnet - keeps stuffing box/packing far above cryogenic media, prevents ice on stem, maintains seal (per BS 6364/MSS SP-134); (iii) parts cryogenically treated (LN2 soak - stabilize dimensions, eliminate residual stress); (iv) cryogenic test (100% LN2 seal+operation before shipment); (v) for LNG, LOX, LIN, LAR, ethylene, ammonia; (d) one of widest temp ranges in butterfly valves (-196 to +600°C). High-pressure type PN64 (Class 400): (a) reinforced body (thick wall per ASME B16.34 for Class 400); (b) RTJ flange (metal ring seal); (c) high-strength stem (anti-blowout, large diameter); (d) high-strength bolts (grade B7/L7, proper torque); (e) robust seat (no extrusion); (f) high-torque actuator (sized for PN64); (g) size limit - typically DN≤400-600 (larger = very heavy/custom); (h) test - 1.5×PN = 96MPa hydrostatic. Flow/sealing principle: (1) fully open (0°): disc parallel, low resistance (full-bore); (2) rotating: disc disengages (friction-free), throttles; (3) fully closed (90°): disc cams into seat - bidirectional Class IV/V; (4) bidirectional. Testing: (1) 100% body hydrostatic 1.5×PN; (2) 100% seat leak 1.1×PN - Class IV (or Class V if specified, bidirectional); (3) 100% operation test (per actuator - manual/gear: torque; electric: stroke/time/torque; pneumatic: 0-90°, time, air); (4) cryogenic test (if cryogenic type - 100% LN2 seal + operation); (5) NDT - body (for high pressure/alloy, 100% for PN64); (6) PMI (stainless/alloy); (7) flange dimension (RF/RTJ groove); (8) fire-safe (optional API 607). Maintenance: (1) periodic exercise (monthly); (2) inspect leaks (body, stem, flanges); (3) seat - metal seal, inspect annually (re-lap if Class IV/V degraded, replace if damaged); (4) stem packing - graphite, tighten/replace; (5) actuator maintenance per type: (i) manual - lubricate stem/gear, inspect handwheel; (ii) bevel gear - lubricate gearbox, inspect self-lock; (iii) electric - check motor, wiring, limit switches, manual override; (iv) pneumatic - FRL (drain filter, replace element), solenoid, air lines, spring (single-acting - test fail-safe quarterly); (6) cryogenic type - extended bonnet, verify no ice, cryogenic packing; (7) flange bolts - re-torque (thermal cycling); (8) high-pressure PN64 - more frequent NDT/inspection. Troubleshooting: (a) seat leakage (>Class IV): disc not fully closed (actuator stroke/limit), seat scratched (re-lap/replace), torque insufficient (actuator undersized), pressure too low; (b) high torque/jammed: packing too tight, disc seized, actuator undersized (PN64), stem bent; (c) electric actuator not operating: no power, motor burnt, limit switch faulty, wiring; (d) pneumatic actuator not operating: no/low air, solenoid faulty, air leak, spring broken (single-acting); (e) external leak stem: packing loose/worn (tighten/replace); (f) external leak flange: bolts loose (re-torque), gasket/RTJ ring failed (replace); (g) cryogenic ice on stem: extended bonnet issue (inspect), packing leak (ice forms - repair). Important: (a) Class IV = low leakage, NOT zero (if zero needed, Class V optional or soft-seal valve); (b) PN64 high-pressure = size limit, RTJ flange, confirm; (c) cryogenic -196°C = special design (extended bonnet, cryogenic materials/test), not standard; (d) flanged = load-bearing (but support large pipe); (e) actuator choice - specify manual/gear/electric/pneumatic at order (we size per DN/PN); (f) not for heavy abrasive slurry (metal seal scratches - knife gate; small particles OK); (g) RTJ ring = single-use (replace when flange opened); (h) warranty: 18 months (valve), 12 months (electric/pneumatic actuator). With proper actuator selection, periodic exercise, and actuator maintenance, this triple-offset hard-seal flanged butterfly valve provides reliable Class IV/V sealing service in severe high-temp/high-pressure/cryogenic pipelines.

• Petrochemical + Oil + Gas Industry

Refineries (crude oil, high-temperature oil transport, high-pressure process lines), natural gas gathering/transmission, chemical reagent pipelines, petrochemical product processing. Triple-offset metal hard seal resists oil/corrosion and high pressure difference; Class V optional for hazardous media; high-pressure type PN64/RTJ for high-pressure oil/gas; pneumatic option for ESD emergency shutdown; manual/gear for non-automated lines. Reliable for petrochemical high-pressure/hazardous pipelines.

• Power Generation Industry

Thermal/nuclear power plants - boiler pipelines, main steam pipelines, heat-conducting oil, steam turbine circulating water, chemical water high-pressure systems, FGD flue gas. Triple-offset metal hard seal handles high-temp steam (to 600°C) and high pressure; flexible actuation (manual for auxiliary, electric for boiler interlock, pneumatic for fast safety); flanged RF/RTJ robust for high-pressure steam. Cryogenic type for LNG power/air separation. Reliable for power plant high-temp/high-pressure steam/water.

• Metallurgical Industry

Steel plants - blast furnace high-temperature flue gas, steelmaking, smelting, coking plant heat-conducting oil/steam pipelines. Wear-resistant metal hard seal (Stellite/graphite) resists flue gas dust scouring; temperature to 600°C for continuous high-temp operation; large DN (to DN1800) for blast furnace gas mains; bevel gear for large DN manual operation. Reliable for metallurgy high-temp/dust-laden pipelines.

• Water Treatment + Desalination Industry

Industrial sewage treatment, municipal water supply, seawater desalination, circulating water. Stainless/duplex body + NAB (nickel aluminum bronze) disc resist seawater corrosion; metal hard seal or optional EPDM/PTFE for water; full-bore low flow resistance saves pumping energy for large water mains; manual/gear for simple on-off, electric for automated treatment plant. Class IV sufficient for water (or soft seal option for zero leakage). Reliable for water treatment/desalination corrosion-resistant pipelines.

• Cryogenic LNG + Other Industries

LNG liquefaction/terminals/tankers (cryogenic type to -196°C, LCB/316L + extended bonnet), industrial gas (LOX/LIN/LAR), pharmaceutical, food processing, mining, environmental protection. Wide temperature -196~600°C covers both cryogenic and high-temp; versatile materials (WCB/SS/alloy/duplex/NAB/PTFE) for diverse media; flexible actuation per automation level. 18-month warranty (valve), 12-month actuator, OEM/ODM customization (actuator type, size to DN1800, PN64, cryogenic, Class V seal). Reliable for cryogenic LNG and diverse severe-service pipelines.

Our Flange Hard Seal Butterfly Valves are manufactured under an ISO 9001:2015 certified quality management system, with every valve undergoing rigorous inspection and testing at each production stage - because these triple-offset metal hard-seal flanged butterfly valves are used for petrochemical high-pressure/hazardous, power plant high-temp steam, metallurgy high-temp dust, water treatment/desalination, cryogenic LNG (-196°C) where seat leakage (Class IV/V failure), body burst at PN64, stem blowout, cryogenic seal failure (ice/leak), metal seal wear/delamination, actuator failure (manual/gear/electric/pneumatic), or RTJ flange leak can cause hazardous media release, steam burns, LNG cryogenic hazard, energy loss, process disruption, and safety incidents (the high-pressure PN64, cryogenic -196°C, triple-offset metal seal, and multi-actuation make body strength, seal quality, cryogenic treatment, and actuator torque critical additional quality points).

Raw material control: every body/disc/stem/seat material batch comes with material certificate (chemical + mechanical per heat); carbon steel WCB verified; stainless SS304/316/316L (CF8/CF8M) verified; alloy WC6/WC9 verified (Cr, Mo, V - high temp); low-temp LCB/LCC verified (impact test at -46°C, for cryogenic); duplex verified (PREN); nickel aluminum bronze (NAB) verified (Cu, Al, Ni, Fe - seawater/wear); Stellite/hard alloy welding wire verified; Cr13 verified; graphite (purity, flexural strength) verified; stem CF8/CF8M/SS verified; fasteners (B7/L7 for high-pressure/cryogenic) verified.

Body manufacturing: (a) casting (WCB/CF8/CF8M/LCB) or forging (alloy, high-pressure); (b) heat treatment (normalizing/tempering, solution annealing for stainless, cryogenic treatment for LCB/304L - LN2 soak to stabilize dimensions); (c) 100% visual; (d) NDT - radiographic/ultrasonic of body (for PN40+ and alloy/cryogenic, 100% for PN64); (e) wall thickness (per ASME B16.34 - critical for PN64); (f) flange machining - RF face or RTJ groove (precision, for high pressure); (g) seat recess, stem bore/bearing; (h) extended bonnet (for high-temp/cryogenic - integral or welded); (i) chemical/mechanical/hardness per heat; (j) low-temp impact test (for LCB/LCC - V-notch Charpy at -46°C); (k) surface treatment - paint or high-temp paint; (l) nameplate (stainless, engraved).

Disc manufacturing: (a) cast/forged disc (stainless/CI/duplex/NAB); (b) reinforcement for DN>1000; (c) machining (sealing cone, stem hole); (d) hard alloy overlay (Stellite) or Cr13 + graphite seal surface; (e) precision grinding + lapping (matched with seat); (f) PTFE lining (if corrosion option) - bond test; (g) dynamic balance.

Seat manufacturing: (a) stainless ring + hard alloy overlay (ground/lapped), or Cr13 ring + graphite interlayer assembly; (b) dimensional check, hardness, graphite integrity; (c) replaceable bolt-in design.

Stem: (a) CF8/CF8M/SS machined; (b) anti-blowout collar (critical for PN64); (c) surface treatment (nitriding); (d) for cryogenic - cryogenically treated.

Actuator manufacturing/test (per type): (a) manual handwheel - ductile iron/cast steel, strength test, surface finish; (b) bevel gear - gearbox (cast iron), gears (hardened steel), ratio test, self-lock test, lubrication; (c) electric actuator - motor (insulation class F/H), gear reduction, limit switches, torque switch, 4-20mA positioner (if regulation), IP67, operation test (stroke, time, torque), manual override test; (d) pneumatic actuator - cylinder/end caps (aluminum, anodized), piston/rack/pinion (hardened), spring (spring steel, shot peened, fatigue test - for single-acting), seals (NBR/PU, low temp optional), assembly + test: operation (0-90°), torque, time, air tightness, single-acting spring return, cycle test (sample); (e) cryogenic actuator (if cryogenic type - low-temp seals, extended stem coupling).

Assembly: (1) install seat; (2) install stem + anti-blowout + packing (graphite; extended bonnet packing for cryogenic/high-temp); (3) install disc (verify triple-offset geometry); (4) lap disc-to-seat (matched, verify contact pattern - Class IV or Class V); (5) mount actuator (couple, bolts - torque, per type: manual/gear/electric/pneumatic); (6) install accessories (if electric/pneumatic: solenoid, limit switch, FRL, positioner); (7) full stroke test (per actuator, 0-90°, smooth); (8) set actuator stops/limits.

Pressure/testing: (1) 100% body hydrostatic shell 1.5×PN - (for PN64 = 96MPa, high-pressure test); (2) 100% seat leak 1.1×PN - Class IV (standard) or Class V (if specified, bidirectional, measure leak rate); (3) 100% air tightness; (4) 100% operation test (per actuator - manual/gear: torque; electric: stroke/time/torque; pneumatic: 0-90°, time, air); (5) cryogenic test (if cryogenic type - 100% LN2 seal + operation test, simulate -196°C, verify no ice/jam/leak); (6) strength + seal per API 598/API 6D.

Function testing: open/close 90° (per actuator), operation time (electric/pneumatic), actuator torque, bidirectional seat sealing (Class IV/V), triple-offset friction-free (verify), flange RF/RTJ dimension, face-to-face, PMI (stainless/alloy), hardness (Stellite HRC≥40, Cr13), cryogenic impact (LCB/LCC), RTJ groove dimension, actuator test (per type), extended bonnet dimension (cryogenic/high-temp), gear self-lock (bevel gear type). Cryogenic quality (if cryogenic type): (a) materials - LCB/LCC (impact tested), 304L/316L (low carbon); (b) cryogenic treatment - all pressure parts LN2 soaked (stabilize dimensions, eliminate residual stress); (c) extended long-neck bonnet - length per BS 6364/MSS SP-134 (keeps packing above frost point); (d) cryogenic test - 100% LN2 immersion, seal test (zero leak), operation test (smooth, no ice jam); (e) low-temp seals (actuator, packing - graphite, no rubber that becomes brittle); (f) no grease (or low-temp grease) - regular grease freezes at -196°C.

Traceability system: (a) unique serial number on nameplate; (b) database links: raw material cert (including low-temp impact for LCB), heat number, casting/forging batch, hard alloy overlay record, NDT report, hydrostatic test (including PN64 high-pressure), seat leak report (Class IV/V), cryogenic test report (if cryogenic), actuator test report (per type), production date, inspector, order/customer; (c) full batch traceability.

Coating & marking: exterior - epoxy/polyester powder (blue) or high-temp silicone paint (for >200°C); cryogenic type - special low-temp paint or bare stainless; interior - bare; valve permanently marked with DN, PN, max temp, body material, disc material, seal material/class, standard, flow direction (bidirectional), manufacturer, year, serial number, cryogenic marking (if cryogenic - "CRYOGENIC", temp range, material), actuator type; nameplate (stainless, engraved - for cryogenic, use low-temp adhesive or rivets).

Documentation: shipped with hydrostatic test report, material certificate (including low-temp impact if cryogenic), seat leak report (Class IV/V), hard alloy hardness cert, cryogenic test report (if cryogenic), actuator test report (per type), RTJ ring cert (if RTJ), traceability ID, and installation/operation/maintenance manual (including high-pressure safety, cryogenic handling, actuator maintenance per type).

Warranty: 18 months from shipment or 12 months from installation (valve body); 12 months from shipment (electric/pneumatic actuator + accessories); manual/gear actuators covered under valve 18-month (no electronics); extended warranty and third-party inspection (BV, SGS, TUV), fire-safe API 607, cryogenic cert, PED/CE, API available.

Q: Which actuator should I choose - manual, bevel gear, electric, or pneumatic?

A: This valve offers four actuation options on the same valve body (via ISO 5211 standard mounting pad) - manual handwheel, bevel gear, electric actuator, or pneumatic actuator. The right choice depends on your DN size, automation requirement, available power (air/electricity), safety needs (fail-safe), budget, and operation frequency. 1. Manual handwheel: (a) How it works: handwheel directly coupled to stem - operator rotates handwheel → stem/disc 90°; (b) Advantages: (i) simplest, most reliable (no electronics/pneumatics); (ii) no power needed; (iii) lowest cost; (iv) visual position (handwheel orientation); (c) Disadvantages: (i) operator effort high for large DN/high pressure (may be impossible); (ii) no remote/automation; (iii) slow (operator speed); (d) Use when: (i) DN≤150 (small, low torque - one operator can handle); (ii) non-automated lines, occasional operation; (iii) budget-sensitive; (iv) no power/air available; (v) auxiliary/standby lines. 2. Bevel gear (worm gear / spiral bevel): (a) How it works: handwheel → bevel gear set (gear ratio) → stem - mechanical advantage reduces effort; (b) Advantages: (i) labor-saving 50-80% (gear ratio - one operator can operate DN200-1800); (ii) self-locking (worm gear holds position, no drift under pressure/vibration - safety); (iii) no power needed; (iv) reliable, low maintenance; (v) handwheel position indicator; (c) Disadvantages: (i) no remote/automation; (ii) slower than direct manual (more turns); (iii) more expensive than manual; (d) Use when: (i) DN200-1800 (large, high torque - manual impossible); (ii) non-automated large-bore lines; (iii) need self-locking (no drift); (iv) no power/air; (v) most common for large DN manual operation. 3. Electric actuator: (a) How it works: electric motor (AC220/380V/DC24V) → gear reduction → stem - on-off or 4-20mA regulation; (b) Advantages: (i) remote/automated - DCS/PLC, signal feedback; (ii) precise regulation (4-20mA positioner, ≤±1% accuracy); (iii) no air compressor needed (only power); (iv) explosion-proof (Exd II BT4 optional - for hazardous areas); (v) manual emergency override (handwheel on power loss); (c) Disadvantages: (i) slower (15-60s, vs pneumatic 1-3s); (ii) not fail-safe on power loss (unless battery backup - stays last position or drifts); (iii) more expensive than manual/gear; (iv) motor/gear maintenance; (v) heavier for high torque; (d) Use when: (i) automated lines (remote control, DCS/PLC); (ii) flow regulation (4-20mA - pressure/flow/level control); (iii) no compressed air available; (iv) explosion-proof needed (Exd actuator); (v) medium operation frequency. 4. Pneumatic actuator: (a) How it works: rack-pinion piston (compressed air) → stem - double-acting (air both directions) or single-acting (spring-return fail-safe); (b) Advantages: (i) fast (1-3 seconds - much faster than electric); (ii) fail-safe (single-acting spring-return FC/FO - for ESD/hazardous); (iii) high cycle life (1+ million); (iv) simple (no motor), high torque for size; (v) cheaper than electric for high torque; (c) Disadvantages: (i) needs compressed air (0.4-0.7MPa, FRL, air lines - infrastructure cost); (ii) air lines can freeze (cryogenic/wet air); (iii) no power = no operation (unless single-acting spring returns); (iv) noise (exhaust); (d) Use when: (i) fast operation needed (1-3s - boiler safety, ESD); (ii) fail-safe needed (hazardous media, ESD - single-acting FC/FO); (iii) high-frequency cycling (pneumatic robust); (iv) compressed air available; (v) hazardous areas (with ATEX solenoid). Selection decision guide: (a) Small DN (≤150) + no automation + budget → manual handwheel; (b) Large DN (200-1800) + no automation → bevel gear (labor-saving, self-locking); (c) Automation + flow regulation + no air → electric (4-20mA, DCS/PLC); (d) Automation + fast/fail-safe + air available → pneumatic (1-3s, spring-return ESD); (e) Hazardous area (Zone 1/2) + no air → electric explosion-proof (Exd II BT4); (f) Hazardous area + air + fail-safe → pneumatic + ATEX solenoid (single-acting FC); (g) Large DN + automation → electric or pneumatic with gearbox (high torque); (h) Cryogenic LNG → pneumatic (dry air) or manual (electric may need low-temp; pneumatic air lines must be dry); (i) High-pressure PN64 → bevel gear or high-torque electric/pneumatic (high closing torque needed). 

Actuator sizing (critical for PN64/high pressure): (a) determine valve torque (depends on DN, PN, pressure, seal - we provide); (b) actuator torque ≥ valve torque × 1.5-2 (safety factor); (c) electric: motor power + gear ratio sized for torque; (d) pneumatic: cylinder bore + air pressure sized for torque; (e) PN64 high pressure = much higher torque (actuator may be 2-3× larger than PN16); (f) we size actuator per your valve specs (don't choose yourself). Interchangeability / future upgrade: (a) ISO 5211 mounting pad - all actuators mount via standard pad; (b) you can upgrade later (e.g., manual → electric, or electric → pneumatic) by swapping actuator (same valve body); (c) specify at order if you plan to upgrade (we pre-machine pad); (d) coupling/stem extension may need adjustment. Common mistakes: (a) using manual for DN>200 (operator can't close - valve leaks); (b) using electric for ESD (electric doesn't fail-safe on power loss - need battery/UPS; pneumatic spring-return is natural fail-safe); (c) using pneumatic when no air supply (then need compressor - electric may be cheaper overall); (d) undersized actuator for PN64 (valve doesn't close); (e) no FRL for pneumatic (dirty air damages actuator/solenoid); (f) choosing bevel gear for automated line (no remote - need electric/pneumatic). Important: (a) specify actuator type at order (manual/gear/electric/pneumatic - we size per DN/PN); (b) for electric, specify voltage (AC220/380V/DC24V), on-off or regulation (4-20mA), explosion-proof needed?; (c) for pneumatic, specify double-acting or single-acting (FC/FO), air pressure, accessories (solenoid/limit switch/positioner/FRL); (d) we supply valve + actuator assembled/tested (specify configuration); (e) warranty: manual/gear = 18 months (valve), electric/pneumatic = 12 months (actuator); (f) we can advise per your DN/PN/automation/safety/power. This valve = manual handwheel (small DN), bevel gear (large DN, self-locking), electric (remote/regulation/explosion-proof), or pneumatic (fast/fail-safe/high-cycle) - all on same body via ISO 5211 pad, specify your needs.

Q: What is the difference between Class IV and Class V leakage for this metal hard seal, and which do I need?

A: This valve uses a multi-layer metal hard seal and achieves ANSI/FCI 70-2 Class IV leakage as standard, with Class V optional for high-precision requirements. Understanding the difference is critical for selecting the right seal for your application. ANSI/FCI 70-2 leakage classes explained: (a) FCI 70-2 (formerly ANSI B16.104) is the standard for control valve seat leakage (also used for butterfly valves); (b) classes are based on leakage rate at test pressure (1.1× rated or 50 psi, whichever lower), with water or air; (c) Class I: no test (agreed between buyer/seller - basically no leakage guarantee); (d) Class II: 0.5% of rated capacity (moderate leakage - soft-seat with metal backup); (e) Class III: 0.1% of rated capacity (low leakage - well-fitted soft seat); (f) Class IV: 0.01% of rated capacity (very low leakage - single-seated metal-to-metal, or soft seat with metal piston ring); (g) Class V: very low leakage - defined as maximum leakage per inch of seat size per psi differential (e.g., 5×10⁻⁴ ml/min per inch per psi - essentially bubble-tight for practical purposes, near zero); (h) Class VI: bubble-tight zero leakage - zero visible bubbles (air test), measured in bubbles per minute (e.g., 0 bubbles for soft seat with elastomer); This valve's seal options: (a) Standard - Class IV: (i) 0.01% of rated flow leakage; (ii) achieved with multi-layer metal hard seal (stainless + hard alloy overlay, or Cr13 + graphite interlayer), precision ground + lapped; (iii) for most industrial applications where small leakage is acceptable (steam, oil, gas, water - process lines where tiny leak doesn't cause hazard); (iv) cost-effective (standard); (b) Optional - Class V: (i) near-zero leakage (per inch per psi formula - essentially bubble-tight for metal seal); (ii) achieved with higher-precision lapping, better compliance (graphite interlayer optimized), tighter tolerances, possibly Stellite on both disc + seat; (iii) for hazardous media (toxic, flammable, expensive), high-value media, environmental-sensitive (zero-ish leak required), steam (where leak = energy loss); (iv) more expensive (extra lapping/inspection); (c) If you need true zero (Class VI): (i) metal hard seal cannot reliably achieve Class VI (metal surfaces always have microscopic gaps); (ii) use soft-seal butterfly valve (EPDM/PTFE/FKM - Class VI bubble-tight, but temp limited ≤200°C); (iii) or gate valve / ball valve (for zero leakage, but higher cost/larger); (iv) this valve's metal seal = Class IV/V (not Class VI) - by design. Which do you need? (a) Choose Class IV (standard) if: (i) general process lines (steam, oil, gas, water) where 0.01% leak is acceptable; (ii) non-hazardous media; (iii) cost-sensitive; (iv) most common (80% of applications); (b) Choose Class V (optional) if: (i) hazardous media (toxic, flammable - e.g., H2S, chlorine, solvents); (ii) high-value/expensive media (leak = cost); (iii) environmental regulations (near-zero emission required); (iv) high-pressure steam (leak = significant energy loss); (v) vacuum service (minimize air ingress); (c) Choose soft-seal (different valve) if: (i) need true zero leakage (Class VI); (ii) media temp ≤200°C (soft seal limit); (iii) water, oil, gas (non-high-temp); (d) Note: for cryogenic LNG, Class V is recommended (LNG leak = hazard + waste) - this valve's cryogenic type can achieve Class V with graphite seal + precision lap. Leakage test method: (a) Class IV: test with air or water at 1.1×PN, measure leak rate (must be ≤0.01% of rated Cv); (b) Class V: test with water at specified pressure, measure leak in ml/min per inch of seat per psi (must meet formula); (c) we provide leak test report with each valve (specify Class IV or V at order). Seal material and leakage: (a) stainless + Stellite overlay - hard, wear-resistant, Class IV (Class V with precision lap); (b) Cr13 + graphite interlayer - graphite provides compliance, can achieve Class V more easily (graphite conforms), but graphite may wear over time; (c) if Class V required, we recommend Cr13 + graphite interlayer (better compliance) or double Stellite + ultra-precision lapping; (d) specify at order. Common mistakes: (a) expecting Class VI (zero) from metal seal (impossible - use soft seal); (b) ordering Class IV for hazardous media (should be Class V); (c) not specifying leakage class (we default to Class IV); (d) using Class IV for vacuum (air ingress - use Class V or soft seal); (e) confusing FCI 70-2 with API 598 (API 598 is for on-off valves, "zero visible" = different standard; FCI 70-2 is for control valve leakage classes). API 598 vs FCI 70-2: (a) API 598 (valve inspection/test) - for on-off valves, "zero visible leakage" at seat (bubble-tight for soft seal, "no visible" for metal - less precise); (b) FCI 70-2 / ANSI B16.104 - for control valves, defines Class I-VI with measurable leakage rates (more precise); (c) this valve tested to API 598 (shell/seat) and FCI 70-2 Class IV/V (seat leakage class) - both; (d) if you need a specific class, specify FCI 70-2 Class IV or V. Important: (a) Class IV = 0.01% leak (standard, acceptable for most); (b) Class V = near-zero (optional, for hazardous/high-value); (c) Class VI (zero) = not achievable with metal seal (use soft-seal valve); (d) specify at order (we default Class IV); (e) we test and report leakage class per FCI 70-2; (f) for cryogenic LNG, Class V recommended; (g) we can provide sample leak test data per size/class. This valve = Class IV standard (0.01% leak), Class V optional (near-zero, for hazardous/high-value) - specify your media/hazard level, we recommend leakage class.

Q: This valve offers cryogenic type to -196°C - how is that different from standard, and when do I need it?

A: The cryogenic type of this valve is specially designed for cryogenic media down to -196°C (LNG, LOX, LIN, LAR, ethylene, ammonia) - it is significantly different from the standard (-29~425°C) valve in materials, bonnet design, treatment, testing, and seals. When you need cryogenic type: (a) LNG (Liquefied Natural Gas) - liquefaction plants, storage tanks, terminals, tankers, refueling stations (-162°C); (b) LOX (Liquid Oxygen) - air separation, medical, aerospace (-183°C); (c) LIN (Liquid Nitrogen) - food freezing, electronics, medical (-196°C); (d) LAR (Liquid Argon) - welding, metallurgy (-186°C); (e) Liquid Ethylene - petrochemical (-104°C); (f) Liquid Ammonia - refrigeration, fertilizer (-33°C); (g) any media below -29°C (standard WCB carbon steel becomes brittle below -29°C - must use low-temp material). Key differences from standard valve: (a) Body material: (i) standard: WCB carbon steel (min -29°C), WC6/WC9 alloy (high temp), SS304/316; (ii) cryogenic: LCB/LCC (low-temp carbon steel, min -46°C, impact tested) or 304L/316L (austenitic stainless steel, low carbon - min -196°C, no brittle transition); (iii) why low carbon (L grade): carbon >0.08% causes carbide precipitation, reduces toughness at low temp - 304L/316L have ≤0.03% C; (iv) austenitic stainless (304L/316L) has no ductile-brittle transition (remains tough to -196°C and below) - ideal for cryogenic; (b) Extended long-neck (cryogenic) bonnet: (i) standard: short bonnet, packing near body (hot/cold conducts to packing); (ii) cryogenic: extended long-neck bonnet - stem/packing chamber is far above the cryogenic media (bonnet length per BS 6364 / MSS SP-134, typically 200-350mm depending on DN/temp); (iii) purpose: keeps packing/stem at near-ambient temperature (above 0°C), prevents ice formation on stem (ice would damage packing/seal, cause leak/jam), maintains reliable sealing; (iv) mandatory for cryogenic service (per standards); (c) Cryogenic treatment of parts: (i) all pressure-containing parts (body, disc, stem, seat) are cryogenically treated - soaked in liquid nitrogen (-196°C) for several hours, then slowly warmed; (ii) purpose: (1) stabilize dimensions (austenitic stainless can undergo phase transformation at low temp - cryo-treatment completes it before service, prevents dimensional drift/leak after thermal cycling); (2) eliminate residual stress (from welding/machining); (3) improve wear resistance; (iii) done before final machining/lapping; (d) Packing/seals: (i) standard: flexible graphite (OK to -200°C actually - graphite is good for cryogenic), but may use PTFE + graphite combination; (ii) cryogenic: low-temp flexible graphite (or expanded PTFE) - no rubber (rubber becomes brittle/glassy at -196°C, leaks); (iii) live-loaded packing (springs) - compensates thermal contraction; (iv) stem surface - polished (no scratches that leak); (e) Actuator: (i) standard: manual/gear (OK), electric with NBR seals (NBR becomes brittle below -20°C), pneumatic with NBR seals; (ii) cryogenic: low-temp actuator seals (FKM/silicone or special), extended stem coupling (actuator above frost line), heater optional (if actuator in cold area); (iii) manual/bevel gear may be preferred for cryogenic (pneumatic air lines can freeze if moisture; electric may need low-temp); (f) Fasteners/gaskets: (i) low-temp bolts (L7/B8 - austenitic stainless or low-temp alloy, not B7 which is brittle at low temp); (ii) gasket - spiral wound stainless + graphite (or RTJ metal ring - good for cryogenic); (g) Testing: (i) standard: hydrostatic + seat leak at ambient; (ii) cryogenic: 100% cryogenic test - valve immersed in liquid nitrogen (-196°C), then seat leak test (zero leak, Class V recommended), operation test (open/close smooth, no ice jam, no binding); (iii) low-temp impact test for LCB/LCC material (V-notch Charpy at -46°C); (h) Marking: clearly marked "CRYOGENIC", temp range (-196°C), material (LCB/304L), extended bonnet. Why extended bonnet is critical: (a) at -196°C, if packing is near the cold body, moisture in air freezes on stem (ice forms); (b) ice abrades packing, causes leak; ice can jam stem; (c) extended bonnet moves packing up to warm zone (above frost line - typically >0°C); (d) bonnet length depends on temp (colder = longer bonnet) and DN; (e) per BS 6364 (UK cryogenic valve standard) and MSS SP-134 (US) - mandatory for temps below -40°C. Cryogenic test procedure (what we do): (a) pre-cool valve slowly (to avoid thermal shock); (b) immerse in LN2 bath (-196°C) for 15-30 minutes (until stable); (c) seat leak test - apply gas pressure (1.1×PN or 50 psi), measure leak (must be ≤Class V / zero); (d) operation test - operate open/close 5+ times (verify smooth, no jam, torque reasonable); (e) inspect - no ice formation on stem/packing area (if ice = packing leak, fail); (f) warm up slowly, re-test at ambient (verify no damage from thermal cycling); (g) 100% of cryogenic valves undergo this (not sample). Installation/operation for cryogenic: (a) keep dry - moisture freezes, use dry air/gas for testing; (b) slow cool/warm (thermal shock can crack - avoid rapid temp changes); (c) support pipe (cryogenic pipes contract - use expansion joints); (d) insulation (valve may need insulation, but leave actuator/bonnet accessible); (e) vent - cryogenic liquid vaporizes (expands 600× for LNG) - ensure vent paths; (f) PPE - cryogenic burns (liquid -196°C), use cryogenic gloves/face shield; (g) no grease (or low-temp grease) on stem (regular grease freezes); (h) exercise periodically (prevent seat freeze). Common mistakes: (a) using standard WCB valve for LNG (WCB brittle at -162°C - cracks, catastrophic); (b) no extended bonnet (ice on stem = leak/jam); (c) rubber seals (brittle at -196°C); (d) B7 bolts (brittle at low temp - shear); (e) no cryogenic test (may leak at temp even if OK at ambient); (f) rapid cooling (thermal shock); (g) using pneumatic with wet air (air lines freeze). Material selection for cryogenic: (a) -46 to -100°C (ammonia, some refrigerants): LCB/LCC low-temp carbon (cheap, tough); (b) -100 to -196°C (ethylene, LNG, LOX, LIN): 304L/316L austenitic stainless (no brittle transition, to -196°C); (c) <-196°C (liquid hydrogen -253°C, helium -269°C): special alloys (Invar, aluminum, titanium) - custom; (d) this valve's cryogenic type = -196°C (304L/316L + LCB option). Cost/lead time: (a) cryogenic type = +20-50% cost (special materials, extended bonnet, cryo-treatment, 100% LN2 test); (b) lead time = +10-15 days (cryo-treatment + test); (c) specify at order. Important: (a) cryogenic type is special - not just "same valve with different material" (extended bonnet, cryo-treatment, low-temp seals, 100% LN2 test); (b) for LNG/LOX/LIN below -46°C, MUST use cryogenic type (standard valve fails); (c) we provide cryogenic test report + material cert (low-temp impact); (d) extended bonnet length per BS 6364/MSS SP-134; (e) Class V seal recommended for cryogenic (LNG leak = hazard); (f) actuator for cryogenic - manual/bevel gear preferred, or electric/pneumatic with low-temp seals + dry air; (g) we can advise per your cryogenic media/temp. This valve = standard -29~425°C, cryogenic type to -196°C (LCB/304L/316L + extended long-neck bonnet + cryogenic treatment + 100% LN2 seal/operation test + low-temp seals/fasteners) - for LNG/LOX/LIN/LAR, specify cryogenic at order.

Q: Flanged RF vs RTJ connection - which do I need for my pressure/temperature?

A: This valve offers flanged connection with two facing types: RF (Raised Face) and RTJ (Ring Type Joint) - selected based on your pressure, temperature, and pipe flange standard. RF (Raised Face) flange: (a) Design: flange face has a raised ring (1.5-2mm high) above the flat flange face; (b) Sealing: gasket placed on the raised face - (i) non-asbestos fiber (low pressure/temp); (ii) spiral wound metal (stainless + graphite/flexible graphite - for medium/high pressure/temp); (iii) PTFE envelope (corrosive); (iv) rubber (low temp water); (c) bolts compress gasket between two raised faces → seal; (d) Pressure/temp range: (i) general Class 150-300 (PN10-40), temp to ~450°C (with spiral wound graphite); (ii) can go to Class 400 (PN64) with special spiral wound gasket + high-temp bolts, but RTJ is more reliable; (e) Advantages: (i) cheap, common, easy to install; (ii) gasket reusable (sometimes); (iii) easy to align; (iv) wide availability; (f) Disadvantages: (i) gasket can blow out at very high pressure/temp; (ii) not ideal for Class 400+ / >450°C; (iii) gasket replacement needed when flange opened. RTJ (Ring Type Joint) flange: (a) Design: flange faces have grooves (octagonal or oval cross-section) on both mating flanges; (b) Sealing: metal ring (soft iron, low-carbon steel, Monel, Inconel) sits in grooves; bolts compress ring → ring deforms/plastically flows into grooves → metal-to-metal seal; (c) Pressure/temp range: (i) Class 400-2500 (PN64-420), temp to 600°C+ (metal ring handles high temp); (ii) standard for high-pressure/high-temp (oil/gas, steam, petrochemical); (d) Advantages: (i) very high pressure/temp capability (no gasket blowout - metal ring); (ii) reliable seal at extreme conditions; (iii) compact (ring takes less space than gasket); (e) Disadvantages: (i) more expensive (groove machining + metal ring); (ii) ring is single-use (deforms - must replace every time flange opened); (iii) requires precise groove machining; (iv) harder to align (ring must fit grooves); (v) not for low pressure (ring may not seal properly at low compression). Which do you need? (a) Choose RF if: (i) PN10-40 (Class 150-300) standard; (ii) temp ≤450°C; (iii) general water/steam/oil/gas; (iv) cost-sensitive; (v) most common (80% of applications); (b) Choose RTJ if: (i) PN64 (Class 400) high-pressure type; (ii) temp >450°C (high-temp steam, hot oil); (iii) hazardous high-pressure oil/gas; (iv) reliability critical (no gasket blowout); (v) petrochemical/refinery high-pressure; (c) For cryogenic LNG: (i) RTJ is excellent (metal ring seals at -196°C, no rubber gasket); (ii) or RF with spiral wound stainless + graphite (also OK); (d) For this valve's high-pressure type (PN64): RTJ recommended (RF with special gasket is possible but RTJ is standard for Class 400). Flange standards: (a) ANSI B16.5 - American standard, covers NPS 1/2"-24" (DN15-600), Class 150-2500; (b) ASME B16.47 - large diameter NPS 26"-60" (DN650-1500), Series A (API 605) and Series B; (c) DIN 2501/2543-2547 - German/European, PN10-40; (d) JIS B2220 - Japanese, 10K/16K/20K/30K; (e) GB/T 9115 - Chinese, PN series; (f) match your pipe flange standard (we can make any). Gasket/ring selection: (a) RF + spiral wound (316 + flexible graphite) - for steam/oil/gas, -200~550°C, PN10-40 (most common for this valve); (b) RF + PTFE envelope - corrosive chemical, ≤200°C; (c) RF + rubber (EPDM/NBR) - water, ≤120°C; (d) RTJ + soft iron ring - general high pressure/temp; (e) RTJ + low-carbon steel - high pressure; (f) RTJ + Monel/Inconel - corrosive high pressure; (g) cryogenic: RTJ metal ring (excellent) or RF spiral wound stainless+graphite. Bolt selection (related to flange): (a) RF general: carbon steel grade 8.8/10.9 (≤350°C); (b) high temp (>400°C): alloy B16/B7 (≤500°C) or stainless B8 (≤800°C); (c) cryogenic: L7 (low-temp alloy) or B8 (austenitic stainless); (d) PN64/RTJ: high-strength B7/L7, proper torque (torque wrench); (e) we specify bolts per pressure/temp. Installation tips: (a) RF: (i) clean flange faces (no scratches); (ii) place gasket centered; (iii) torque bolts cross-pattern, 3 passes incremental; (iv) re-torque after thermal cycling; (b) RTJ: (i) clean grooves (no debris); (ii) inspect ring (no scratches - use new ring every time); (iii) place ring in groove (octagonal ring has direction - check); (iv) torque to spec (ring must deform - under-torque = leak); (v) replace ring every time flange is opened (deformed ring won't reseal); (c) both: support pipe (flange/valve not load-bearing for large DN). Common mistakes: (a) using RF + rubber gasket at PN40/400°C (gasket blows/burns - use spiral wound or RTJ); (b) reusing RTJ ring (deformed - leaks); (c) wrong flange standard (ANSI vs DIN - bolt holes don't align); (d) no torque wrench (uneven bolt tension = leak); (e) using RTJ at low pressure (ring doesn't seal - under-compression); (f) scratching RTJ groove (leak - must machine/repair). Important: (a) RF for PN10-40 (standard), RTJ for PN64 high-pressure/high-temp; (b) match your pipe flange standard (ANSI/DIN/JIS/GB); (c) RTJ ring = single-use (replace every opening); (d) we provide gasket/ring with valve (specify pressure/temp/standard); (e) for this valve, specify RF or RTJ + flange standard at order; (f) high-pressure PN64 = RTJ recommended. This valve = flanged RF (standard, PN10-40) or RTJ (high-pressure PN64/high-temp), ANSI B16.5/B16.47/DIN/JIS/GB - specify your pressure/temp/pipe flange standard, we provide matching facing + gasket/ring + bolts.

Q: How does this compare to the Pneumatic Flange Hard Seal Butterfly Valve (both triple-offset metal hard seal flanged)?

A: Both this valve (Flange Hard Seal) and the Pneumatic Flange Hard Seal Butterfly Valve use triple-offset metal hard seal technology with flanged connection - but they differ in actuation flexibility, size range, pressure, and target applications. Here's the detailed comparison to help you choose. Similarities (both): (a) Triple-offset (three-eccentric) structure - friction-free rotation, self-energizing bidirectional seal, long seal life (3-5× ordinary); (b) Metal hard seal - stainless + hard alloy (Stellite) overlay or Cr13 + graphite, high temp/wear resistant, Class IV/V leakage; (c) Flanged connection - RF/RTJ, robust, load-bearing; (d) Severe-service - high-temp, high-pressure, corrosive, cryogenic industrial pipelines; (e) On-off or flow regulation (with positioner); (f) DCS/PLC compatible (with electric/pneumatic actuator); (g) Fire-safe (metal seal, API 607 optional); (h) Wide materials (WCB/SS/alloy/duplex/LCB); (i) Wide temp (-196~600°C including cryogenic). 

Which to choose - decision guide: (a) Choose Flange Hard Seal (this valve) if: (i) need flexible actuation - may want manual now, electric later (interchangeable via ISO 5211); (ii) large DN with manual/gear operation (DN200-1800, no automation); (iii) mixed automation levels across a project (some manual, some electric, some pneumatic - same valve body); (iv) budget-sensitive (manual/gear cheaper than pneumatic); (v) no compressed air for some valves (use manual/gear/electric); (vi) standard size DN50-1800, PN10-40 (PN64 HP); (b) Choose Pneumatic Flange Hard Seal if: (i) need pneumatic specifically - fast 1-3s, fail-safe spring-return, high-cycle; (ii) ESD/hazardous (pneumatic fail-safe FC/FO); (iii) ultra-large DN (custom to DN4000 - this valve max DN1800); (iv) ultra-high pressure PN100 (this valve max PN64); (v) high-frequency cycling (pneumatic 1+ million); (vi) compressed air available and preferred; (c) If both could work: (i) need manual/gear + maybe automate later → this valve (flexible, upgradeable); (ii) need pneumatic now + fast/fail-safe → pneumatic flanged; (iii) DN>1800 → pneumatic flanged (custom DN4000); (iv) PN>64 → pneumatic flanged (PN100); (v) cryogenic LNG → both have cryogenic type (this valve with manual/gear may be simpler for cryogenic; pneumatic needs dry air). Actuation flexibility is the key differentiator: (a) This valve = "one body, four actuators" - (i) manual handwheel (small DN, cheap); (ii) bevel gear (large DN, self-locking, no power); (iii) electric (remote/regulation/explosion-proof); (iv) pneumatic (fast/fail-safe); (v) all mount via ISO 5211 pad - interchangeable; (b) Pneumatic flanged = "pneumatic only" - (i) if you need manual/electric, it's a different product; (ii) but pneumatic is optimized (fast, fail-safe, high-cycle); (c) for a project with mixed valves (some manual, some automated), this valve simplifies sourcing (same body, different actuators); (d) for a project all-pneumatic, pneumatic flanged is optimized (and can go larger/higher pressure). Size/pressure comparison: (a) This valve: DN50-1800, PN10-40 (PN64 HP) - covers standard industrial range; (b) Pneumatic flanged: DN50-1200 (custom DN4000), PN10-40 (PN100 HP) - smaller standard but custom ultra-large + ultra-high pressure; (c) if you need DN1200-1800 with manual/gear → this valve (pneumatic flanged standard max DN1200, DN1800 would be custom); (d) if you need DN>1800 → pneumatic flanged (custom DN4000); (e) if you need PN64-100 → both (this valve PN64, pneumatic PN100). Can this valve be made pneumatic? (a) Yes - this valve offers pneumatic as one of four options; (b) but the Pneumatic Flange Hard Seal product is optimized for pneumatic (standard pneumatic actuator sizing, faster delivery, pneumatic-specific accessories); (c) if you need pneumatic + DN>1200 or PN>64, use the Pneumatic Flange Hard Seal product; (d) if you need pneumatic + DN50-1200 + PN10-40, either works (this valve's pneumatic option = same as pneumatic flanged product). Common mistakes: (a) ordering pneumatic flanged when you need manual (wrong product - this valve offers manual); (b) ordering this valve with manual for DN>1800 (not available - use pneumatic flanged custom DN4000); (c) ordering this valve for PN>64 (not available - use pneumatic flanged PN100); (d) not considering future automation (this valve is upgradeable via ISO 5211 - better if you might automate later). Important: (a) both are triple-offset metal hard seal flanged (same sealing technology); (b) key differentiator: this valve = flexible actuation (manual/gear/electric/pneumatic) + DN50-1800 + PN64; pneumatic flanged = pneumatic-only + DN50-1200 (custom DN4000) + PN100 + fast/fail-safe; (c) tell us your: DN, PN, temp (including cryogenic?), medium, actuation preference (manual/gear/electric/pneumatic or flexible), fail-safe requirement, size/pressure extremes - we recommend the right valve; (d) we manufacture both (can provide comparison quote). This valve (Flange Hard Seal) = best for flexible actuation choice (manual/gear/electric/pneumatic), standard large bore DN50-1800, medium-high pressure PN64, mixed automation projects, budget-sensitive manual/gear large-bore; Pneumatic Flange Hard Seal = best for pneumatic-specific fast/fail-safe, ultra-large DN custom DN4000, ultra-high pressure PN100, high-frequency cycling, all-pneumatic projects.

Q: What is the warranty, and what does it cover (including cryogenic type and different actuators)?

A: Warranty period: (a) Valve body (triple-offset body, disc, seat, stem, flange, extended bonnet): 18 months from shipment date (or 12 months from installation date, whichever comes first); (b) Manual handwheel + bevel gear actuator: covered under valve 18-month warranty (no electronics - mechanical only); (c) Electric actuator + accessories (motor, gear, limit switches, positioner, solenoid if electric): 12 months from shipment date; (d) Pneumatic actuator + accessories (cylinder, piston, rack, pinion, spring, solenoid, limit switch, positioner, FRL): 12 months from shipment date (actuator manufacturer warranty passed through); (e) wear/consumable parts (packing, gasket/RTJ ring, graphite seal wear, actuator seals, spring fatigue, FRL filter, motor brushes) - not covered under normal wear. What is covered (valve body + manual/gear): (a) body defects - casting/forging defects (porosity, cracks, wrong material), wall thickness; (b) triple-offset geometry - manufacturing error (wrong offsets, jamming); (c) hard alloy overlay - delamination, wrong hardness (factory defect - not normal wear); (d) seat/disc - manufacturing defect (not wear from particles); (e) stem - material defect, anti-blowout failure; (f) flange - RF/RTJ groove defect; (g) manual handwheel/bevel gear - manufacturing defect (gear tooth break, handwheel crack, self-lock failure); (h) cryogenic type - extended bonnet defect, cryogenic treatment defect, material defect (LCB/304L), cryogenic seal failure under rated -196°C (if properly installed); (i) leakage - Class IV/V failure under normal use (not due to wear/particles/wrong pressure). What is covered (electric actuator): (a) motor - manufacturing defect (coil burn under rated voltage, insulation failure); (b) gear reduction - manufacturing defect (gear tooth break); (c) limit switches/torque switch - factory defect; (d) positioner (4-20mA) - electronics defect; (e) manual override - mechanism defect; (f) housing - IP67 failure (factory defect, not damage). What is covered (pneumatic actuator): (a) cylinder/piston/rack/pinion - manufacturing defect; (b) spring (single-acting) - manufacturing defect/fatigue under normal cycle (not beyond rated cycles); (c) solenoid/limit switch/positioner - factory defect (coil, electronics); (d) air tightness - factory defect (not due to damaged fittings/unauthorized repair). What is NOT covered: (a) exceeding ratings - pressure >PN64, temp >material rating (e.g., WCB at 600°C, standard valve at -196°C cryogenic), wrong medium (heavy slurry scratches seal); (b) normal wear - graphite/Stellite seal wear from dust/particles, packing wear, actuator seal wear, spring fatigue beyond rated cycles, RTJ ring deformation (single-use item), motor brushes; (c) improper installation - no pipe support (body/flange deformation), wrong gasket/RTJ ring, insufficient bolt torque (flange leak), wrong voltage (solenoid/motor burns), no FRL (dirty air damages pneumatic actuator), wrong actuator sizing (customer-specified undersized); (d) improper maintenance - no exercise (seizure), no FRL drain (water in actuator), packing over-tightened (stem damage), reusing RTJ ring (leak), no gear lubrication (bevel gear wear); (e) cryogenic-specific: (i) using standard valve for cryogenic (not the cryogenic type - WCB brittle at -196°C); (ii) rapid cooling/thermal shock (cracks - customer operation); (iii) moisture/ice in air lines (freeze - customer air quality); (iv) no extended bonnet (if customer removed/modified); (f) accident/damage - impact, fire, freezing, water hammer (from too-fast operation), over-pressure; (g) unauthorized repair/modification - non-genuine parts, field machining, altering actuator, modifying cryogenic bonnet; (h) consequential damages - downtime, product loss (LNG loss), labor, pipe damage, energy loss. Cryogenic type specific warranty notes: (a) cryogenic parts (LCB/304L body, extended bonnet, low-temp seals) covered for 18 months under rated -196°C; (b) cryogenic test - we provide 100% LN2 test report (proves factory integrity); (c) damage from thermal shock (rapid cool/warm) = not covered (must slow cool/warm per manual); (d) ice on stem from packing leak = if factory packing defect = covered; if from improper installation/no extended bonnet = not covered; (e) cryogenic actuator (if electric/pneumatic equipped) = 12 months (low-temp seals). High-pressure PN64 specific: (a) body burst/failure at rated PN64 = covered (if manufacturing defect, with NDT report); (b) bolt failure - if factory-supplied bolts fail at rated torque = covered; if customer uses wrong bolts = not covered; (c) RTJ ring = single-use wear item (not covered); (d) actuator undersized - if WE sized and it can't close at PN64 = covered (re-size/replace); if customer specified = not covered. Actuator specific: (a) electric motor burn from wrong voltage = not covered; (b) pneumatic spring failure (single-acting) within rated cycle life = covered; beyond = wear; (c) air leak at fittings - if factory assembly = covered; if customer tubing/fittings = not covered; (d) FRL - filter element, lubricator oil = wear items (not covered); (e) bevel gear - self-lock failure from factory = covered; from lack of lubrication = not covered. Warranty claim process: (a) notify us within 30 days of discovering defect (email: Contact@thankfulmaterial.com, phone: +86-15094398934); (b) provide evidence: photos/videos, valve nameplate (DN/PN/material/temp/date/serial, cryogenic marking if applicable, actuator type), operating conditions (actual pressure/temp/medium, cryogenic media), maintenance records, actuator model, air supply quality (if pneumatic), voltage (if electric), test reports (cryogenic if applicable); (c) we evaluate - may request return (small valve) or on-site inspection (large/cryogenic/high-pressure - we may send engineer); (d) remedy: repair (send parts/engineer), replacement (valve/actuator/parts), refund; (e) timeline: 7-30 days (cryogenic/high-pressure/custom may take longer). Extended warranty options: (a) valve 24/36 months - +5-15%; (b) electric/pneumatic actuator 24 months - +10-20%; (c) cryogenic type extended - +15-25%; (d) service contract - annual inspection/maintenance (optional, especially for cryogenic/high-pressure); (e) specify at order. Service/support beyond warranty: (a) spare parts supply - seat ring (metal/Stellite/graphite), stem, packing (graphite/PTFE), gaskets/RTJ rings, fasteners (low-temp B8/L7), actuator parts (manual gear, electric motor/gear, pneumatic piston seals/spring/solenoid/positioner), for 10+ years; (b) technical support - actuator sizing, cryogenic handling, high-pressure installation, maintenance, troubleshooting (free, lifetime); (c) on-site service - engineer visit for installation/inspection/repair (optional, paid; cryogenic/high-pressure recommended); (d) cryogenic re-test - factory LN2 re-test after overhaul; (e) actuator repair/rebuild/upgrade - factory or field (including manual→electric/pneumatic upgrade via ISO 5211); (f) OEM/ODM - custom valves/actuators/cryogenic. Important warranty notes: (a) valve + manual/gear = 18 months, electric/pneumatic actuator = 12 months; (b) warranty starts at shipment (not delivery/installation); (c) 12 months from installation cap for valve; (d) keep records - installation date, operating pressure/temp (data logger, especially cryogenic), air quality (pneumatic), voltage (electric), maintenance (exercise, FRL drain, gear lubrication, bolt torque), cryogenic cool/warm rates - helps with claims; (e) material cert + test reports (including cryogenic LN2 test, high-pressure hydrostatic) - keep (proves factory quality); (f) don't exceed ratings (PN/temp/medium - voids warranty, dangerous; especially cryogenic - standard valve at -196°C = catastrophic); (g) genuine parts - use our spare parts (non-genuine voids); (h) cryogenic - don't modify extended bonnet, use slow cool/warm, dry air (if pneumatic); (i) RTJ ring = single-use (replace every opening); (j) pneumatic - use clean/dry air + FRL (water/dirt damage not covered); (k) electric - use correct voltage, check motor/gear periodically; (l) wear items (packing, seal wear, RTJ ring, FRL filter, motor brushes) are expected maintenance (not defects). This valve = 18-month valve body + manual/gear actuator warranty (including cryogenic type/extended bonnet under rated conditions), 12-month electric/pneumatic actuator + accessories warranty, extendable - with reliable spare parts (metal seat, cryogenic packing, RTJ rings, all actuator types) and lifetime technical support (including cryogenic LNG handling, PN64 high-pressure guidance, and actuator selection/upgrade). Note: always operate within specified pressure (≤PN64, derated at temp), temperature (per material - standard -29~425, high-temp 600, cryogenic -196 with cryogenic type), and medium (not heavy abrasive slurry), use proper installation (pipe support, torque, RTJ ring replacement), perform regular maintenance (exercise, FRL drain if pneumatic, gear lubrication, bolt torque, cryogenic slow cool/warm), use correct voltage (electric) and clean/dry air with FRL (pneumatic) - this prevents most issues and maintains warranty validity.

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