Kirloskar Reflux Valve Multi Door

Comprehensive Engineering Guide: Kirloskar Multi-Door Non-Return Valves (MDNRV)

Designed according to IS 5312 (Part-2) standards, Kirloskar Multi-Door Non-Return Valves (MDNRV) prevent backflow and water hammer in high-flow water transport infrastructure.

Technical Specifications & Configuration

These metal-seated check valves feature hinged doors mounted on a central diaphragm. To deliver zero-leakage performance under pressure, both door rings and diaphragm rings undergo precision machining, scraping, and mirror-lap finishing.

• Fluid Compatibility: Handles clean water with suspended solids up to 5000 PPM.
• Maximum Flow Velocity: Operational threshold capped at $4\text{ m/s}$.
• By-Pass System: Optional IS 5312-compliant bypass valve available for pressure equalization.

Installation & Pipe Preparation

Proper site handling and alignment safeguard the valve against body stress, flange cracking, and premature mechanical wear.

• Lifting & Handling: Anchor rigging to built-in lifting lugs or eye bolts. Never run slings through secondary attachments like bypass piping. Transport with the inlet flange resting horizontally.
• Pipeline Alignment: Verify that mating pipe flanges are parallel to prevent stress concentration. Do not force uneven flanges together by over-tightening bolts.
• Structural Support: Mount the valve on concrete foundation pads to prevent pipe sagging.
• System Integration: Verify that flow direction matches pipe movement, confirm smooth manual door actuation, and calibrate active surge protection equipment before start-up.

Operation & Preventative Maintenance

During pump start/stop cycles, keep the optional bypass valve open to balance internal pressure. Once the main valve doors seat fully, close the bypass line until the next cycle.

Storage Tip: Store rubber component spares in cool, dark environments away from direct sunlight. Flat rubber sheets have an 8-month storage life, while elastomeric O-rings, U-cups, and gaskets remain stable for up to 18 months.

Troubleshooting Protocol

• Seat Leakage: Check whether the bypass valve remains open. If debris is trapped in the seal, attempt to flush it out under flow. For persistent leaks, isolate the line, remove the valve, and inspect for damaged seat rings. Note: Precision seat ring re-machining must be performed at KBL factories.
• Flange Leakage: Re-torque flange bolts evenly. If leaks persist, inspect for flange misalignment or replace damaged gaskets.
• Vibration or Hammering: Anchor adjacent upstream and downstream piping to rigid foundation supports.

Warranty & End-of-Life Recycling

KBL provides warranty coverage for 12 months from commissioning or 18 months from factory dispatch, whichever comes first. This coverage applies to defects in material and workmanship, provided operating limits are respected. At end-of-life, components can be returned through the KBL Product Recycle Program (customercare.recycle@kbl.co.in) for safe material reclamation.