Stainless Steel 316 Ball Valve
Stainless Steel 316 · DN15–DN200 · PN16 · Corrosion Resistant
The SS316 ball valve resists chlorides, acids and steam condensate that destroy carbon steel — the default choice for chemical, marine and food plants.
Full-bore SS316 with PTFE seats keeps Cv high and pressure drop low across the line.
Key Features
Bubble-Tight Shutoff
Soft PTFE seats give zero-leakage shutoff for gas, water and chemical service.
Low Torque
Floating and trunnion designs keep operating torque low for lever or compact actuators.
Anti-Blowout Stem
Stem shoulder and live-loaded packing prevent ejection under line pressure.
Fire-Safe Design
Metal-to-metal backup seat holds line pressure after a fire (design principle; no API 607 certificate held).
Actuator Ready
ISO 5211 flange accepts pneumatic or electric actuators and gearboxes.
Full / Reduced Bore
Full-bore models give unobstructed Cv; reduced-bore saves weight and cost.
Technical Specifications
| Parameter | Specification |
|---|---|
| Body Material | WCB Carbon Steel / SS304 / SS316 / CF8M |
| Ball / Trim | SS304 / SS316 / 17-4PH |
| Seat Material | PTFE / RPTFE / PEEK / Metal |
| Size Range | DN15 – DN600 (1/2" – 24") |
| Pressure Rating | PN16 (ANSI 150 / 300) |
| End Connection | Flanged / Threaded / Welded / Wafer / Tri-clamp |
| Operation | Lever / Gear / Pneumatic / Electric Actuator |
| Bore | Full Bore / Reduced Bore |
| Fire Safe | Fire-safe design with metal backup seat (design principle; no API 607 certificate held) |
| Leakage Class | Bubble-tight, ANSI ISO 5208 Rate A (soft seat) |
| Standards | API 608 / ISO 17292 / GB/T 12237 |
| Certification | ISO 9001:2015, MTC available |
How to Specify a Stainless Steel 316 Ball Valve
The stainless 316 ball valve is specified for chemistry, not for looks. The question is always which wetted parts need to be 316 and which do not.
Which parts actually see the medium
Body, ball, stem and seat all contact the medium. A 316 body with a 304 ball is common and adequate for mildly corrosive service; for chlorides or acids specify 316 trim as well.
316 is for chlorides and general chemicals
Molybdenum in 316 gives it resistance to chlorides and dilute acids that 304 does not have. For seawater, produced water or hypochlorite, 316 is the minimum rather than a premium.
Seat material is usually the limiting part
PTFE covers most chemicals within its temperature range. Where the medium attacks PTFE, or the temperature exceeds it, the choice moves to PEEK or a metal seat — the body material is not the constraint.
Threaded, welded or flanged
Small stainless ball valves are often threaded or welded. Welded ends remove a potential leak path on hazardous service; threaded ends make maintenance easier on utility lines.
Confirm the pressure and temperature derating
A soft-seated ball valve loses pressure rating as temperature rises. For hot chemical service, check the derated figure rather than the ambient one.
Installation & Maintenance
Use the correct sealant or none at all
Threaded stainless joints gall easily and sealant choice matters. On welded ends, purge properly or the weld oxidises inside the bore.
Support stainless pipework independently
Stainless has a higher expansion coefficient than carbon steel. Where the two are joined, the difference shows up as load on the valve.
Avoid mixing stainless and carbon steel fasteners in wet service
Galvanic corrosion at the joint is a common and avoidable failure.
Do not over-torque the stem packing
Over-tightened packing raises operating torque and wears the stem. Adjust until it just stops weeping.
Common Specification Mistakes
Assuming all “stainless” is the same
304 and 316 behave very differently in chloride service.
Ignoring the seat when the body is 316
The seat is usually the first part to fail.
Using carbon steel fasteners on a stainless valve outdoors
Galvanic corrosion at the flange.
Frequently Asked Questions
What is the difference between floating and trunnion ball valves?
Floating ball valves seat the ball against the downstream seat by line pressure (DN15–DN150). Trunnion-mounted balls are held by top and bottom shafts for larger sizes (DN200+) and higher pressures.
Which seat material should I choose?
PTFE / RPTFE for most chemicals and clean fluids up to +200°C. PEEK for higher temperature. Metal seat for slurry, abrasive or high-temperature service.
Can ball valves be used for throttling?
Ball valves are best for on/off. For modulating duty use our V-port control ball valves or control valves, which keep a stable characteristic curve.
Applications & Use Cases
Oil & Gas
Pipeline isolation, tank farm and loading arms with fire-safe soft seats.
Water & Utilities
Municipal water, HVAC and irrigation with flanged or wafer ends.
Chemical
Corrosive media handled in SS316 or PTFE-seated bodies.
Food & Pharma
Tri-clamp and polished SS316 ball valves for hygienic lines.
