Products Description
Rubber seated butterfly valve with EPDM, NBR, or FKM liner. Zero leakage performance for water, wastewater, chemicals, and HVAC systems. Manual or actuated options available.
Key Technical Specifications
| Item | Specification |
|---|---|
| Valve Type | Rubber Seated Butterfly Valve |
| Seat Material | EPDM / NBR / FKM (Viton) |
| Model | Wafer / Lug / Flanged |
| Nominal Size | DN50 – DN1200 |
| Pressure Rating | PN10 / PN16 / ANSI150 |
| Body Material | ASTM A536 / EN GJS‑450 Ductile Iron |
| Disc Material | SS304 / SS316 / Coated Ductile Iron |
| Stem Material | SS304 / SS316 |
| Operation | Lever handle / Worm gear / Pneumatic / Electric |
| Face to Face | ISO 5752 Series 20 (wafer) or Series 28 (lug) |
| Top Flange | ISO 5211 (actuator mounting) |
| Coating | Fusion Bonded Epoxy (250‑300 microns) |
| Leakage Rate | Zero (ISO 5208 Rate A) |
| Standards | ISO 5752 / EN 593 / API 609 |
Product Features
Rubber Seat Gives You Bubble‑Tight Shut‑Off
The rubber liner presses tightly against the disc edge. When you close the valve, the rubber compresses. The seal becomes completely bubble‑tight. No water passes through. No leakage at all.
Three Rubber Compounds for Any Media
EPDM works for water, wastewater, and mild chemicals. NBR works for oils, fuels, and hydraulic fluids. FKM (Viton) works for high heat and aggressive chemicals. Choose the right rubber for your job.
Three Connection Types Fit Your Pipeline
Wafer type fits between two flanges. It is compact and low cost. Lug type has threaded inserts. You can remove downstream pipe without draining the line. Flanged type bolts directly to your pipe flanges.
Low Flow Resistance Saves Pumping Energy
When fully open, the disc sits edge‑on to the flow. Water passes around it with very little resistance. Your pump works less hard. Your electricity bill goes down.
Corrosion‑Proof Coating Extends Valve Life
We coat every valve body with fusion bonded epoxy. Thickness is 250 to 300 microns. This protects against rust, chemicals, and weather. The valve will outlast the pipes around it.
Core Selling Points
Manual or Actuated – You Choose
Need a simple lever handle? We have it. Need a worm gear for large pipes? We have it. Need pneumatic or electric actuation for automation? We have it. One valve design works for all.
ISO 5211 Top Flange for Easy Automation
The top flange follows the international standard. Need to automate later? Remove the handle. Bolt on a pneumatic or electric actuator. No need to buy a new valve.
No Gaskets Needed for Wafer Installation
The rubber seat extends to the flange faces. When you tighten flange bolts, the rubber compresses and seals. No separate gaskets to buy or install. Saves time and money.
Lockable Lever Stops Unauthorized Use
The lever handle has a locking plate with 10 positions. Insert a padlock to lock the handle at any setting. Fire lines, public areas, and remote sites stay secure.
Self‑Locking Gear for Large Valves
For DN200 and above, choose the worm gear option. The gear design locks itself. When you stop turning the handwheel, the valve stays where you set it. No brake needed.
Application
Municipal Water Supply – Isolation for main lines and branch lines. EPDM seat is drinking water approved.
Sewage Treatment Plants – Raw sewage, activated sludge, and effluent lines. EPDM resists sewage chemicals.
Pump Stations – Suction and discharge isolation. Low flow resistance saves pumping energy.
HVAC Systems – Chilled water and hot water isolation. Compact size fits in mechanical rooms.
Chemical Processing – Dosing lines and chemical transfer. Choose FKM seat for chemical resistance.
Food and Beverage – Process water and CIP lines. Food‑grade EPDM or FKM seat available.
Power Generation – Cooling water lines for condensers. Large sizes up to DN1200.
Irrigation Systems – Main line isolation and branch control. Lockable lever prevents water theft.
Fire Protection – Isolation for fire pump test lines. Lockable handle meets code requirements.
Marine and Offshore – Seawater cooling and ballast lines. Choose SS316 disc and FKM seat.
Industrial Manufacturing – Process water, cooling water, and compressed air.
Media Compatibility by Rubber Type
| Media Type | EPDM | NBR | FKM |
|---|---|---|---|
| Fresh water | ✓ Excellent | ✗ No | ✓ Good |
| Raw water | ✓ Excellent | ✗ No | ✓ Good |
| Wastewater | ✓ Excellent | ✗ No | ✓ Good |
| Sea water | ✓ Good | ✗ No | ✓ Excellent |
| Hot water (80°C) | ✓ Good | ✗ No | ✓ Excellent |
| Hot water (120°C) | ✗ No | ✗ No | ✓ Excellent |
| Air / compressed air | ✓ Excellent | ✓ Good | ✓ Good |
| Oils / fuels | ✗ No | ✓ Excellent | ✓ Good |
| Hydraulic fluids | ✗ No | ✓ Excellent | ✓ Good |
| Mild chemicals | ✓ Good | ✗ No | ✓ Excellent |
| Aggressive chemicals | ✗ No | ✗ No | ✓ Excellent |
| Acids (dilute) | ✗ No | ✗ No | ✓ Good |
| Food products | ✓ Yes (food grade) | ✗ No | ✓ Yes (food grade) |
Materials That Ensure Long Service Life
| Component | Standard Material | Properties | Upgrade Option |
|---|---|---|---|
| Body | Ductile Iron ASTM A536 65‑45‑12 | 450 MPa tensile, 12% elongation | SS316 for corrosive environments |
| Disc | SS304 | Good corrosion resistance | SS316 (salt water), Nylon‑coated DI (abrasion) |
| Rubber seat | EPDM | -20°C to 80°C, excellent for water | NBR (oil), FKM (high heat/chemicals) |
| Stem | SS304 | Good strength, corrosion resistant | SS316 for salt water or chemicals |
| Stem O‑rings | EPDM or NBR | Seals stem from media | FKM for high temperature |
Accessories
Hand Lever with Locking Plate – Standard on manual valves up to DN300. Locks at 10 positions. Padlock not included.
Worm Gear Operator – For DN200 and above. Self‑locking. Includes position indicator (0° to 90°). Handwheel diameter 200‑400mm.
Limit Switch Box – Mounts on ISO 5211 top flange. Provides open/closed electrical feedback. Mechanical or proximity switches.
Pneumatic Actuator – Double‑acting or spring‑return (failsafe). Includes solenoid valve and speed controllers. For automated operation.
Electric Actuator – On‑off or modulating (4‑20mA). Weatherproof (IP67) or explosion‑proof (ATEX). Manual override standard.
Positioner (for Modulating Control) – Converts 4‑20mA signal to precise disc position. Accuracy within ±1%. For pneumatic actuators.
Flange Bolt Sets – Grade 8.8 zinc plated. Includes bolts, nuts, washers. Correct length for wafer installation.
Performance Testing
Air‑Tightness Test (ISO 5208 Rate A – Zero Leakage):
Close valve fully. Apply 0.6 bar air pressure to one side.
Submerge valve in water. Watch for bubbles for 60 seconds.
Result: No bubbles = zero leakage. This is the strictest test for rubber seated valves.
Hydrostatic Seat Test (High Pressure):
Close valve fully. Apply 1.1 times rated pressure with water.
PN16 valve → 17.6 bar. Hold pressure for 60 seconds.
Result: Zero leakage allowed. Record result on certificate.
Hydrostatic Shell Test (Body Strength):
Open valve partially (protects seat from over‑compression).
Fill body with water. Apply 1.5 times rated pressure.
PN16 valve → 24 bar. Hold for 60 seconds.
Result: No water through body, disc, or stem seals.
Rubber Seat Compression Test:
Measure seat compression after assembly.
Proper compression is critical for zero leakage.
Too little compression = leaks. Too much compression = hard operation.
