Home » Products » Excess Flow Valve
Product List

Excess Flow Valve

The Excess Flow Valve (EFV) is a special safety valve intended to be used in the house connection line of natural or other gas systems. It is typically installed at the outlet of the tapping saddle at the branch off point or on the house connection line, but can be installed at other locations and applications as well.


Function:

The EFV's mechanism senses increased flow rates caused by accidental breaking of the house connection line, e.g. as a result of mistaken excavation operation or such. At normative flow rates, the EFV remains open with minimal obstruction to the gas flow, as required by the designated application. When the flow rate supersedes a preset value, the EFV automatically and immediately shuts off the outflow of gas to prevent the possibility of accidental ignition.

Operation Principal:

The EFV is a fully mechanical valve. Its closing body is spring biased at the open position to avoid obstruction to the flow (VN) and prevent early shutoff. In case of breakage in the downstream pipe, the flow reaches the specified closing flow (VS). The pressure difference caused by the flow at the preset closing flow rate exerts a force on the closing body greater then the spring bias, thus forcing the closing body to move towards the valve seat. Once the closing body starts to move, the balance of forces on it changes and it shuts instantly.
Re-arming: After the downstream pipe is repaired, over flow (VL) creates equilibrium and the spring can move the closing body back to its original position. Thus the EFV is re-armed and ready for operation.
If the EFV type is without over flow (VL), in order to rearm the EFV a manual pressure must be applied.

Design Features:

Fully mechanical
Unique design results in very low head loss at operation flow
Easy installation




Components and Materials:

Plastic Parts – PolyAcetal (POM-thermoplastic polymer)
Rod – Stainless Steel or Brass (depending on model)
Overflow Orifice - Brass
Spring – Stainless Steel
Seals – NBR (DIN EN 549 B2)

Application

In PE Gas Conducting Systems.

Compliance to Standards:

DVGW VP 305-2 / Januar 2007
GDF

Industrial Excess Gas Valves

  • Manufactures bronze gate valves and stop valves. Other items in bronze and brass for gas and for water; ball valves, fittings for polyethylene pipes, brackets for water-meters and gas-meters, ball valves with safety lock.
  • Manufactures inflatable seated butterfly valves for a variety of industrial valve requirements including gas, fluid, dry solids processing.
  • Manufactures ball valves for different temperatures and pressures found in the oil, natural gas, chemical and the food processing industries.

    • Valve Systems

  • Manufacturers of instrument valves, manifolds and their accessories for enclosures, double block and bleed, mounting system and monoflange.
  • Manufactures solenoid and multiport valves; water meters for application in water treatment plants.
  • Supplier of manually and automatic driven control valves systems and hydraulic actuators.
    • Excess Flow Valve
    • HDPE Water Pipe
    • HDPE Water Pipe
      HDPE pipe have many advantages compare with other piping materials, such as: Zero Leaks Best for the Environment Best for Consumers Corrosion and Chemical Resistant Lower Life Cycle Costs Perfect for Trenchless Lightweight and Flexible...

      • Tag: HDPE Pipe for Water