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10 variants · flanged, threaded and weld end · to 425 °C

Gate valves, 1/2" to 6", ANSI · JIS · threaded · weld end

Rising‑stem isolation valves in ten variantsflanged ANSI 150 and JIS 10K, threaded NPT and BSPP, and socket weld — in cast iron, cast steel, forged steel A105 or SS316. Most of this range works to 425 °C, far above what a ball valve will take, because they seal on metal and graphite rather than PTFE.

1/2"–6"DN15 to DN150 across the range
425 °CMost variants — graphite packed
800 PSIHighest, on the threaded and weld ends
4 materialsCast iron · cast steel · A105 · SS316

What a gate valve is for, and when not to use one

Fully open or fully shut. Never in between.

A gate valve isolates. A flat or wedge‑shaped gate is driven down across the bore by a threaded stem, and when it is fully closed the gate seats against the body on both faces. Turn the handwheel the other way and the gate lifts clear of the flow path entirely, which is the gate valve’s real advantage: fully open, it presents almost no restriction and almost no pressure drop — a straight, unobstructed bore.

The trade is that it takes many turns rather than a quarter turn, and that it is not a throttling valve. Held part‑open, flow across the partly‑raised gate vibrates it and erodes both gate and seat, and the damage is permanent. If you need to regulate flow rather than shut it off, use a globe valve. If you need fast on‑off, use a ball valve.

  • ⚠ Never run a gate valve part‑open. It is an isolation valve. Throttling on the gate face wrecks the seat, and a wrecked seat cannot be relied on to shut off. Globe valves are built for throttling.
  • 425 °C on most of this range — against 150 °C for the PTFE‑seated ball valves. Gate valves here use graphite packing and metal seating, which is why they take steam and hot oil that a ball valve cannot. The figures.
  • Choose the end type first. Flanged for larger sizes and anything you expect to remove; threaded for small bore and permanent runs; socket weld where a threaded joint is not acceptable. All ten.
  • ⚠ Then choose the flange standard. ANSI 150 and JIS 10K will not bolt to each other despite similar pressure ratings — different bolt circles. Check the pipework, not the pressure.
  • Material spans four grades. Cast iron for water and low‑duty service, cast steel and forged steel A105 for pressure and heat, SS316 for corrosion. Side by side.
  • Every variant is inspected and tested to API 598 — the one standard common to all ten. The full stack.

All ten gate valves, side by side

End type first, then standard, then material.

VariantEndSizeMaterialPressureMax tempChoose it when
ANSI 150 cast ironANSI 150# flange2"–6"Cast iron A126 B150#not statedWater and low‑duty service on ANSI pipework, at the lowest cost in the range.
ANSI 150 cast steelANSI 150# flange2"–6"A216 WCB150 PSI425 °CSteam and hot oil at larger sizes. Built to API 600, the cast gate valve standard.
ANSI 150 forged steelANSI 150# flange1"–1 1/2"Forged A105150 PSI425 °CSmall‑bore flanged runs. Forged rather than cast, to API 602 / BS 5352.
ANSI 150 SS316ANSI 150# flange1"–4"SS316 / CF8M150 PSI425 °CCorrosive duty on ANSI pipework. Two size bands: forged F316 below 2", cast CF8M above.
JIS 10K cast ironJIS 10K flange2"–6"Cast iron A126 B10K429 °CJapanese‑standard pipework, water duty. Will not bolt to ANSI.
JIS 10K SS316JIS 10K flange1"–4"SS316 / CF8M10K425 °CCorrosive duty on JIS pipework. Dimensions confirmed per order — see its page.
Threaded forged steelNPT1/2"–2"Forged A105800 PSI425 °CSmall‑bore high‑pressure runs. 800 PSI and 425 °C from a screwed valve.
Threaded SS316, 200 PSIBSPP or NPT1/2"–2"SS316 CF8/CF8M200 PSI150 °CLight corrosive duty. The only variant limited to 150 °C — a cast, lighter body.
Threaded SS316, 800 PSIBSPP or NPT1/2"–2"F316 forged800 PSIsee pageCorrosive duty at pressure. Four times the 200 PSI version, forged not cast.
Weld end forged steelSocket weld1/2"–2"Forged A105800 PSI425 °CWhere a threaded joint is not acceptable — steam, high temperature, or a no‑leak requirement.
  • ⚠ The end type is the first decision and it cannot be changed later. Flanged comes out of the line without cutting; threaded is cheaper and smaller but permanent in practice; socket weld is permanent and leak‑free. Six of these are flanged, three threaded, one weld end.
  • ⚠ ANSI 150 and JIS 10K do not bolt together. Both sit near 1.6–2 MPa and their bolt circles differ, so the pressure rating tells you nothing about whether the valve will fit. Check the flange on the pipework.
  • The threaded and weld‑end valves are the high‑pressure ones. 800 PSI against 150 PSI flanged — a small forged body takes far more pressure than a large cast one. If you need pressure at small bore, look at the bottom four rows first.
  • Two ratings worth noting. The threaded SS316 200 PSI is rated 150 °C, as published for its cast CF8/CF8M body; the 800 PSI version’s working temperature is confirmed with the factory on request.
  • The JIS 10K cast iron is rated 429 °C, as published; the ANSI 150 cast iron publishes no temperature, and we obtain one from the factory on request. For hot service, specify cast steel or forged steel and the question does not arise.

The standards each variant is built to

API 598 covers testing on all ten. The design standard is what differs.

VariantDesign and manufactureFace‑to‑faceEndsInspection
ANSI 150 cast ironASME B16.10ASME B16.10ASME B16.1API 598
ANSI 150 cast steelAPI 600ASME B16.10ASME B16.5API 598
ANSI 150 forged steelAPI 602 / BS 5352ASME B16.10ASME B16.5 RFAPI 598
ANSI 150 SS316API 602 / BS 5352ASME B16.10ASME B16.5 RFAPI 598
JIS 10K cast ironASME B16.10ASME B16.10JIS B2212API 598
JIS 10K SS316API 602 / BS 5352ASME B16.10JIS B2220:2012 RFAPI 598
Threaded forged steelAPI 602 / BS 5352ASME B1.20.1 NPTAPI 598
Threaded SS316, 200 PSIASME B16.34ANSI threadAPI 598
Threaded SS316, 800 PSIAPI 602ASME B1.20.1API 598
Weld end forged steelAPI 602 / BS 5352ASME socket weldAPI 598
  • API 600 is the cast steel gate valve standard — a heavier, bolted‑bonnet specification. Only the ANSI 150 cast steel is built to it, and it is the one to quote where a specification says “gate valve to API 600”.
  • API 602 / BS 5352 is the compact forged valve standard, and it covers six of the ten — every forged steel and SS316 variant here. If your specification names API 602, those six are the candidates.
  • API 598 is the common thread. All ten are inspected and tested to it, which is what makes the test pressures on the variant pages comparable.
  • The cast iron variants cite ASME B16.10, as the catalogue prints it. If your specification needs the governing design standard stated formally, ask us and we will get it confirmed.
  • Flange end standards differ between the two JIS variants. JIS B2212 on the cast iron and JIS B2220 on the SS316 — both JIS 10K drillings, but specified against different documents.

Cast iron, cast steel, forged steel or SS316

Four grades, and the choice is mostly about heat and corrosion.

MaterialBody gradeWhere it belongsWatch for
Cast ironASTM A126 BWater, and general low‑duty service on ANSI 150 or JIS 10K pipework. The cheapest bodies in the range.Brittle. Cast iron does not tolerate impact, bending load or thermal shock. Support it properly and do not use it where the line moves.
Cast steelASTM A216 WCBSteam and hot oil at 2" and above. Built to API 600. Takes 425 °C and the highest flanged test pressure here.Carbon steel — no corrosion resistance. Not for aggressive fluids or wet, salty environments.
Forged steelASTM A105Small bore, high pressure. 800 PSI on the threaded and weld‑end valves — more than five times the flanged rating.Also plain carbon steel. No corrosion resistance, same as cast steel.
SS316A182 F316 forged · A351 CF8M castCorrosive fluids and wet or coastal environments. Available flanged on ANSI and JIS, and threaded at 200 or 800 PSI.The 200 PSI threaded version is a cast CF8/CF8M body limited to 150 °C — the only variant here that low.
  • Forged beats cast on pressure; cast beats forged on size. The forged A105 valves reach 800 PSI but stop at 2"; the cast bodies go to 6" but only to 150 PSI. That single trade‑off explains most of this range.
  • ⚠ Cast iron is brittle, and that matters more than its pressure rating. It is a perfectly good body for water at ambient on a well‑supported line, and the wrong choice anywhere there is vibration, impact risk or thermal cycling.
  • Two SS316 grades appear, and the difference is real. A182 F316 is forged and used on the smaller sizes; A351 CF8M is the cast equivalent used above 2". Chemically equivalent, mechanically not identical — forged is the stronger.
  • Neither carbon‑steel grade resists corrosion. If stainless was specified because of the fluid or the environment, A105 and A216 WCB are not substitutes whatever their pressure rating.
  • All ten seal on graphite or metal, not PTFE — which is why most of this range reaches 425 °C where the PTFE‑seated ball valves stop at 150. The temperature table.

Temperature and test pressures, all ten

This is where gate valves pull away from ball valves.

Eight of these ten work to 425 °C. A ball valve from the same range stops at 150 °C, because it seals on a PTFE seat and PTFE softens. A gate valve seats metal to metal and packs the stem with graphite, so the body material becomes the limit rather than a polymer. If the line carries steam or hot oil, that difference is usually the whole reason to specify a gate valve.

VariantNominalShell / body testSeal testGas tightnessMax temperature
ANSI 150 cast iron150#2.06 MPa1.57 MPa0.6 MPanot published
ANSI 150 cast steel150 PSI3.1 MPa2.2 MPa0.6 MPa−29 to 425 °C
ANSI 150 forged steel150 PSI3.0 MPa2.2 MPa0.6 MPa−29 to 425 °C
ANSI 150 SS316150 PSI3.0 MPa2.2 MPa0.6 MPa−29 to 425 °C
JIS 10K cast iron10K2.06 MPa1.57 MPa0.6 MPa429 °C
JIS 10K SS31610K3.0 MPa2.2 MPa0.6 MPa−29 to 425 °C
Threaded forged steel800 PSI21.0 MPa15.4 MPa0.6 MPa−29 to 425 °C
Threaded SS316, 200 PSI200 PSI2.1 MPa1.6 MPa0.6 MPa−29 to 150 °C
Threaded SS316, 800 PSI800 PSI21.5 MPa15.5 MPa0.6 MPaon request
Weld end forged steel800 PSI21.0 MPa15.4 MPa0.6 MPa−29 to 425 °C
  • 425 °C is the headline. Eight of the ten reach it, against 150 °C for a PTFE‑seated ball valve. On steam, hot oil or thermal fluid the gate valve is not a preference, it is the only one of the two that will work.
  • The 800 PSI valves are tested to 21 MPa. That is seven times the flanged shell test, from a body a fraction of the size — forging rather than casting is what buys it.
  • Gas tightness is 0.6 MPa on all ten. The one figure that does not move with class, size or material.
  • Three figures to note. The ANSI 150 cast iron publishes no temperature; the JIS 10K cast iron states 429 °C; and the threaded SS316 800 PSI prints “200” without a unit, which we confirm with the factory on request. For hot service specify cast or forged steel, where the figure is unambiguous.
  • ⚠ These are proof tests, not working pressures. The shell test proves the body, the seal test proves the gate against its seat. Do not design to them.
  • The cast iron variants use different test terminology — “hydraulic body test” and “hermetical seal test” rather than “shell” and “gas‑tightness”. Different catalogue sources, same three tests.

Gate valves — the specification

The range as a whole. Per‑variant figures are on the ten pages.

Size range1/2" to 6" (DN15 to DN150) across the range — threaded and weld end stop at 2", flanged runs from 1" to 6"
End typesANSI 150# flange · JIS 10K flange · NPT · BSPP · socket weld
Body materialsCast iron A126 B · cast steel A216 WCB · forged steel A105 · SS316 (A182 F316 forged, A351 CF8M cast)
Working pressure150 PSI / 150# / 10K flanged · 200 PSI or 800 PSI threaded · 800 PSI weld end
Working temperatureTo 425 °C on eight of ten — the exceptions
Design standardsAPI 600 (cast steel) · API 602 / BS 5352 (forged and SS316) · ASME B16.34 · ASME B16.10by variant
Inspection and testAPI 598 — all ten variants
StemRising stem, handwheel operated. Multi‑turn, not quarter turn
PackingGraphite — which is what allows 425 °C
DutyIsolation only. Fully open or fully shut — never throttle a gate valve. For throttling use globe valves
Not on this pageBall valves for quarter‑turn isolation · globe valves for throttling · butterfly valves for large‑bore isolation
StockHeld in Malaysia or Singapore

Installing and operating a gate valve

Two rules matter more than the rest.

Installing

  • Check the end type and standard match before anything else — flange drilling, thread form or socket dimension. ANSI 150 and JIS 10K do not interchange.
  • Allow headroom for the stem. These are rising stem valves: the stem travels up out of the bonnet as the valve opens. Check dimension H on the variant page, which is the open height, not the closed one.
  • Stem vertical where you can. A horizontal stem loads the packing unevenly and collects debris in the seat pocket. Vertical, handwheel up, is the standard arrangement.
  • Support the weight. Cast bodies at 6" are heavy, and cast iron is brittle — it must not carry pipe load.
  • Clean the line first. Grit driven into the seat faces on first operation is the commonest cause of a gate valve that will not shut off afterwards.

Operating

  • ⚠ Fully open or fully shut. Never in between. Throttling across a part‑raised gate vibrates and erodes both gate and seat, and the damage cannot be undone. Use a globe valve to regulate.
  • Do not over‑tighten on closing. The gate wedges; forcing it past its seat with a bar galls the faces and can jam the valve shut. Hand tight against the stop is enough.
  • Open it fully. A gate left slightly closed is throttling, with all the same damage.
  • Exercise it. A gate valve left untouched for years will often not shut off when it is finally needed — the seat pocket silts up. Operate it periodically.
  • Expect many turns. This is not a quarter‑turn valve. If you need fast isolation, that is a ball valve.

Why buy gate valves from us

Ten variants that differ in end type, standard, material and pressure — all at once.

We start with the end type

Flanged, threaded or socket weld is the first question and it is permanent. Then the flange standard, and ANSI 150 does not bolt to JIS 10K. We check the pipework before quoting a size.

We ask the temperature

It is what separates a gate valve from a ball valve425 °C against 150 — and it also rules out two of these ten. On steam we say so up front.

We will tell you when a gate valve is wrong

If you need to regulate rather than isolate, a gate valve is the wrong tool and it will be damaged doing the job. We will quote a globe valve instead and explain why.

The catalogue is the standard

Every figure on these pages is quoted as the manufacturer prints it, and anything the catalogue does not state clearly — a dimension, a temperature, an order code — we confirm with the factory before anything ships.

Full bills of materials, published

Every variant page lists every part and its material with the manufacturer’s own item numbers — body, gate, seat, stem, packing, bonnet, bolting. No email gate.

Stock in Malaysia and Singapore

Held both sides at a landed price — transport, currency, duties and taxes already inside the figure. Send a size, a standard, or a photo of the flange.

Questions we get asked

The ones that come up on the phone.

What is a gate valve used for?

Isolation — shutting a line off completely, or opening it completely. A flat or wedge‑shaped gate is driven across the bore by a threaded rising stem. Fully open, the gate lifts clear of the flow path, so the valve presents almost no restriction and almost no pressure drop. That straight-through bore is its main advantage over a globe valve.

Can I use a gate valve to control flow?

No. A gate valve is an isolation valve. Held part‑open, flow across the partly‑raised gate makes it vibrate and erodes both the gate and its seat, and that damage is permanent — a throttled gate valve eventually will not shut off at all. If you need to regulate flow, use a globe valve, which is designed for it.

Gate valve or ball valve?

Temperature and speed decide it. Gate valves here work to 425 °C because they seal metal‑to‑metal with graphite packing; the PTFE‑seated ball valves stop at 150 °C. But a ball valve is a quarter turn and a gate valve is many turns. For hot service, gate. For fast or frequent isolation, ball.

Which end type should I order?

Flanged for larger sizes and anything you expect to remove for service — available ANSI 150 or JIS 10K, 1" to 6". Threaded (NPT or BSPP) for small bore, 1/2" to 2", and it is where the 800 PSI ratings live. Socket weld where a threaded joint is not acceptable. All ten compared.

Will an ANSI 150 gate valve bolt to a JIS 10K flange?

No. Both are rated around 1.6 to 2 MPa, which is exactly what makes this an expensive mistake, but the bolt circles differ so the valve will not line up. Check the flange on the pipework — count the holes and measure the bolt circle — rather than matching on pressure.

Why are the threaded valves rated higher than the flanged ones?

Because they are forged rather than cast, and small. The threaded and weld‑end A105 valves reach 800 PSI and are tested to 21 MPa; the flanged cast bodies are 150 PSI tested to about 3 MPa. Forging gives a denser, stronger body, and a small body contains pressure far more easily than a large one. The trade is size: forged stops at 2".

What temperature can a gate valve run at?

425 °C on eight of these ten — cast steel, forged steel and both flanged SS316 variants. The exceptions are the threaded SS316 200 PSI at 150 °C, and two cast iron variants where no figure is published. The full table.

Which material should I choose?

Cast iron for water at ambient on a well‑supported line — cheapest, but brittle. Cast steel A216 WCB for steam and hot oil at 2" and above. Forged steel A105 for small bore at high pressure. SS316 wherever corrosion matters. Neither carbon‑steel grade resists corrosion at all. Side by side.

What is the difference between API 600 and API 602?

API 600 is the standard for cast, bolted‑bonnet steel gate valves — the heavier specification, and here it applies only to the ANSI 150 cast steel. API 602 covers compact forged steel valves, usually with BS 5352, and it governs six of these ten — every forged and SS316 variant. All ten are inspected and tested to API 598. The full stack.

Do I need to allow extra height above the valve?

Yes. These are rising stem valves — the stem and handwheel travel up as the valve opens. The H dimension on each variant page is the height, and you need clearance above that plus room to turn the wheel. It is the dimension most often forgotten on a replacement in a tight space.

Why do some of your tables say the data needs confirming?

Because the manufacturer’s catalogue is the reference for every figure we publish, and where it does not state a value clearly for the exact variant — a dimension, a temperature, an order code — we confirm the governing figure with the factory on enquiry for the size and rating you are buying, so what arrives matches what you designed around.

What sizes do you hold in stock?

1/2" to 6" (DN15 to DN150) across the range, held in Malaysia or Singapore. Threaded and weld end cover 1/2" to 2"; flanged covers 1" to 6" depending on material. Send the size, end type and standard and we will confirm availability and a landed price.

Send the end type, the size and the temperature

We will confirm the flange or thread actually matches, check the temperature against the variant, tell you if a globe valve is the right tool instead, and quote a landed price. Stock in Malaysia and Singapore.

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