Product Name
Manual & High-Mount Vacuum Ball Valve, 316 Stainless — NW16/25/40/50 KF & ISO80, Three-Piece
Product Summary
A three-piece 316 stainless vacuum ball valve, full port, with KF clamp flanges (NW16 / NW25 / NW40 / NW50) or ISO-K (ISO80), sizes 1/2″–2-1/2″. Two builds share the same body: the V-3A with a stainless lever for manual operation, and the V-3AM with an ISO 5211 direct-mount pad and reinforced stem seal that takes a pneumatic or electric actuator without brackets. The serviceable three-piece body opens for cleaning — for lab, semiconductor support and food or pharmaceutical vacuum systems.
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ISO 9001 · CE · Manufacturer since 1999
PDFV-3AM NWISO 5211 Mount · NW/KF · Dimension SheetDownload ↓
Product Description
This vacuum ball valve is a three-piece, full-port valve in cast 316 stainless steel (ASTM A351 CF8M) with PTFE seat and gaskets, built for vacuum and negative-pressure isolation. Flange options cover KF (NW16, NW25, NW40, NW50) and ISO-K (ISO80), sizes 1/2″ to 2-1/2″ — the clamp-style flanges connect and open without tools, the way vacuum lines are built.
Two builds share the same body: the V-3A with a stainless lever for manual operation, and the V-3AM with an ISO 5211 direct-mount pad and reinforced stem seal (Viton O-ring plus PTFE packing) that takes a pneumatic or electric actuator without brackets. Need larger or automated vacuum valves? See the pneumatic vacuum ball valve (ISO-K DN80/DN100), the two-piece manual vacuum ball valve (ISO100), or browse all vacuum valves.
Manual or Direct-Mount?
| V-3A (manual) | V-3AM (direct-mount) | |
|---|---|---|
| Operation | Quarter-turn stainless lever with locking plate | ISO 5211 pad for a pneumatic or electric actuator — lever included for manual use |
| Stem seal | PTFE packing | Viton O-ring plus PTFE packing |
| Best for | Hand-operated isolation points | Lines that are — or may later be — automated |
Key Technical Specifications
| Type | Vacuum ball valve — three-piece, full port |
| Models | V-3A (manual) / V-3AM (ISO 5211 direct-mount) |
| Size range | 1/2″ – 2-1/2″ |
| Connections | KF clamp flange (NW16 / NW25 / NW40 / NW50) or ISO-K (ISO80) |
| Body, cap & ball | ASTM A351 CF8M — the cast form of 316 stainless steel |
| Seat & gaskets | PTFE |
| Stem | ASTM A276 SS316 (V-3A); reinforced seal with Viton O-ring on V-3AM |
| Service | Vacuum and negative-pressure isolation |
Materials
V-3A manual version — 17 parts, matching the numbered circles ①–⑰ in the drawing below. The V-3AM direct-mount version shares the wetted parts and adds the Viton O-ring stem seal, Belleville washer and ISO 5211 hardware (20 parts — see its dimension sheet PDF).
| No. | Part | Material |
|---|---|---|
| 1 | Body | A351 CF8M |
| 2 | Cap | A351 CF8M |
| 3 | Ball | A351 CF8M |
| 4 | Seat | PTFE |
| 5 | Gasket | PTFE |
| 6 | Thrust washer | PTFE |
| 7 | Stem | A276 SS316 |
| 8 | Packing | PTFE |
| 9 | Gland | SS304 |
| 10 | Bevel washer | AISI 301 |
| 11 | Handle | SS304 |
| 12 | Spring washer | SS304 |
| 13 | Bolts | AISI 304 |
| 14 | Bolt washer | AISI 304 |
| 15 | Bolt nut | AISI 304 |
| 16 | Handle sleeve | Vinyl grip |
| 17 | Locking plate | SS304 |
Dimensions (mm)
L, bore Ød1, flange Ød2 and flange thickness C are identical for both builds; H differs (lever vs mounting pad), and S is the V-3AM stem flat. Full drawings in the V-3A and V-3AM dimension sheets (PDF).
| Size / Flange | D1 (V-3A) | H (V-3A) | H (V-3AM) | L | Bore Ød1 | Flange Ød2 | C | S (V-3AM) |
|---|---|---|---|---|---|---|---|---|
| 1/2″ NW16 | 103 | 56 | 38 | 92 | 17 | 30 | 2.3 | 9 |
| 1″ NW25 | 130 | 63 | 49 | 120 | 26 | 40 | 2.5 | 11 |
| 1-1/4″ NW40 | 131 | 68 | 55 | 112 | 41 | 55 | 2.5 | 11 |
| 1-1/2″ NW50 | 153 | 90 | 67 | 133 | 52 | 75 | 2.5 | 14 |
| 2″ NW50 | 194 | 98 | 75 | 146 | 52 | 75 | 2.5 | 14 |
| 2-1/2″ ISO80 | 225 | 109 | 105 | 209 | 83 | 110 | 2.5 | 17 |
Application Fields & Locations
- Laboratory vacuum systems: isolation points on pump lines and manifolds built with KF fittings.
- Semiconductor support lines: roughing and foreline isolation where 316 stainless construction is required.
- Food & pharmaceutical vacuum: negative-pressure processing and packaging lines.
- Vacuum pump protection: shutting off sections for service without venting the whole system.
FAQ
What is the difference between KF (NW) and ISO-K flanges? Both are clamp-style vacuum flanges. KF (also written NW or QF) covers the small sizes — NW16 to NW50 on this valve — sealed with a centering ring and clamped by hand. ISO-K is the larger series; the 2-1/2″ size here uses ISO80. Match the flange to the fittings your system already uses.
Manual or direct-mount — which should I choose? Choose the V-3A lever version for hand-operated isolation points. Choose the V-3AM if the valve is — or may later be — automated: its ISO 5211 pad takes a pneumatic or electric actuator directly, with no bracket to fabricate.
Is it full port? Yes — the bore is unrestricted through the valve (see the Bore Ød1 column in the dimensions table), keeping conductance high on vacuum lines.
Can the valve be serviced? Yes. The three-piece body unbolts, so the seats and ball can be inspected, cleaned or replaced without cutting the valve out of the line.
What seals are used? PTFE seat, gaskets and packing on both builds; the V-3AM adds a Viton O-ring on the stem for a reinforced seal under vacuum.
What is the minimum order? No minimum order quantity — we accept orders of any size, including small trial orders. For small orders, freight is arranged and paid by the buyer. Payment is by T/T — 30% on order confirmation, 70% before shipment.
Sample Policy
We are happy to provide product samples for customers to evaluate quality or conduct testing. The process typically begins with a quotation based on the customer’s specifications.
If the pricing is acceptable, we can offer samples either free of charge or at a cost depending on the product type and availability.
Shipping fees are borne by the customer.
Order Process
After confirming the product requirements and other details with the customer, we will issue a Sales Confirmation for approval. Once confirmed, the customer is required to pay a 30% deposit to proceed with production.
When mass production is completed and the goods pass inspection, the customer must pay the remaining 70% balance before shipment is arranged.
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FAQ
A. How can I request a quote?
Please provide a detailed inquiry sheet including product specifications, materials, quantities, and any special requirements. We will offer a quotation based on your request.
B. What are your quotation terms?
Our quotations are typically based on FOB terms. However, we can also offer CFR, CIF, or other Incoterms upon request.
C. What is your Minimum Order Quantity (MOQ)?
We have no MOQ. We operate on a made-to-order basis and accept orders of any size — trial orders are welcome. For smaller orders, freight is arranged and borne by the buyer.
D. What are your payment terms?
By T/T – 30% down payment upon order confirmation, and 70% balance before shipment.
E. What is your lead time?
Lead time depends on order quantity and specifications. We will confirm the exact schedule when you request a quote.
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