The ANSI Class 150 lug butterfly valve is a Cartiage Hard Back seated, concentric butterfly valve with a threaded lug body. The lug pattern allows each pipe flange to be bolted independently to the valve body, so the downstream pipe can be removed while the upstream side remains pressurized. This makes the valve suitable for end-of-line service, equipment isolation, and maintenance applications where a wafer valve cannot be used.
The PTFE seat extends the valve's service range beyond standard EPDM and NBR seats. PTFE provides near-universal chemical resistance and is suitable for aggressive acids, alkalis, solvents, oxidizing agents, and high-purity process fluids. The seat is dimensionally stable, does not absorb process fluid, and maintains low friction during disc rotation.
| Feature | Technical Benefit |
|---|---|
| Threaded lug body | Independent flange bolting on each side; permits downstream piping removal and end-of-line service. |
| PTFE / RPTFE seat | Broad chemical compatibility and low operating torque across the rated temperature range. |
| Blowout-proof shaft | Machined stem shoulder retains the shaft under full rated pressure, meeting API 609 anti-blowout requirements. |
| PTFE-lined bearings | Upper and lower low-friction bushings reduce torque and provide chemical-resistant shaft support. |
| ISO 5211 top flange | Direct mounting of manual gear operators, pneumatic actuators, and electric actuators. |
| Bubble-tight bidirectional seal | Zero visible leakage in both flow directions when tested to EN 12266-1 Rate A / API 598. |
| Optional disc encapsulation | Ductile iron disc with PTFE/PFA encapsulation or CF8M disc for maximum corrosion resistance. |
| Parameter | Specification |
|---|---|
| Pressure Rating | ANSI Class 150 |
| Body Style | Lug type, threaded inserts |
| Face-to-Face | API 609 Category A / EN 558 Series 20 short pattern |
| Flange Drilling | ANSI B16.5 Class 150 / ASME B16.42 Class 150 |
| Top Flange | ISO 5211 F05-F14 depending on valve size |
| Seat Test | 1.1 times rated pressure, bidirectional, zero visible leakage |
| Shell Test | 1.5 times rated pressure, water, per EN 12266-1 / API 598 |
| Operating Temperature | -29°C to +180°C depending on PTFE grade and pressure |
| Component | Material | Standard |
|---|---|---|
| Body | Ductile Iron / WCB / CF8 / CF8M | ASTM A536 / A216 / A351 |
| Disc | Ductile Iron / CF8M, optional PTFE or PFA encapsulation | ASTM A536 / A351 |
| Seat | PTFE / RPTFE | ASTM D4894 |
| Shaft | SS416 / SS431 / SS316 / 17-4PH | ASTM A276 / A564 |
| Bearing | FRP/PTFE/ bronze | — |
| Stem Seal | NBR | — |
| Internal Fasteners | SS316 | ASTM A276 |
PTFE is inert to most industrial chemicals and process fluids, including concentrated acids, caustic solutions, chlorinated solvents, and oxidizing media. The PTFE seat is well suited to services where EPDM, NBR, and FKM seats are not compatible, and where a low-friction quarter-turn valve is required.
| Seat Material | Typical Temperature Range | Recommended Service |
|---|---|---|
| PTFE | -29°C to +150°C | Strong acids, alkalis, solvents, high-purity water, general chemical service |
| RPTFE | -29°C to +180°C | Thermal cycling, higher-temperature chemical service, reduced cold flow |
| PFA encapsulated disc option | -29°C to +180°C | Aggressive media with full disc corrosion protection |
| Industry | Application |
|---|---|
| Chemical Processing | Acid transfer, solvent handling, reactor feed isolation, corrosive utility lines |
| Water Treatment | Chlorine, hypochlorite, acid, and alkali dosing skids |
| Pharmaceutical | High-purity process utilities, CIP and SIP support lines |
| Food & Beverage | CIP return lines, edible oil processing, sanitary utility isolation |
| Pulp & Paper | Chlorine dioxide, bleaching chemicals, and corrosive process media |
| Industrial OEM | Skid-mounted chemical feed systems and equipment isolation packages |
The ISO 5211 top flange enables direct mounting without custom brackets. Available actuator configurations include:
Factory-mounted actuator assemblies are stroke-tested and shipped as a single unit. Limit switches, positioners, and declutchable manual overrides are available as options.
Each valve receives the following standard inspection and test operations:
Material test certificates per EN 10204 3.1, PMI, and third-party witnessed testing are available on request.
It is used for quarter-turn isolation of corrosive, high-purity, or chemically aggressive fluids in pipelines where independent flange bolting is required. The threaded lug body allows one side of the pipeline to be disconnected while the other side remains sealed.
Yes. The lug body is designed for end-of-line service. The downstream flange can be blanked off, and the upstream side can remain pressurized at the rated Class 150 pressure, provided the bolting and gasket arrangement follows the manufacturer's installation requirements.
PTFE offers excellent chemical resistance and low friction. RPTFE includes a filler that improves dimensional stability and reduces cold flow, making it more suitable for thermal cycling and higher-temperature chemical service.
Standard sizes range from DN50 to DN1200.
Yes. The ISO 5211 top flange supports manual gear operators, pneumatic actuators, and electric actuators. Actuators can be factory-mounted and stroke-tested before shipment.
From raw material inspection to final delivery, every butterfly valve undergoes a comprehensive quality inspection to ensure reliable performance and compliance with international standards.
