IMO Circor type GA Bypass valves GAR, GAS and GAD.

IMO ab offers a special single-acting bypass valve for use in hydraulic systems where a safe and accurate opening pressure is required. The GA valve has a built-in automatic hydraulically acting pressure compensator, which ensures very low pressure increases and pressure variations in case of opening. This applies to both opening and the damped closing process. The valve is thus designed not to create inappropriate pressure surges or pressure variations during opening and/or closing.

Version: IMO GAR, GAS and GAD.

• GAR: Valve body made of Steel with thread IRG
• GAS: Valve body designed for SAE flanges
• GAD: Valve body designed for DIN flanges
• Pressure: up to 100MPa equivalent to 100 bar
• Capacity min: from 0.2 l/s or 10 l/m
• Capacity max: Up to 15 l/s or 1000 l/min through the valve
• Temperature -020 C-90/150C
• Pressure rise max 10% above the set value, but min 0.2 MPa/2 bar above
• Materials: Steel (GAS, GAR) or Nodular Iron (GAD), Viton O-rings
• Sizes GAR ½", ¾, "1" and 1 1/2", (GAS/GAD 015,020,025,040,065 mm)
• Technology: The valve body is a cone shape and the flow area significantly reduces the pipe dimension
• Gas 015 with 4 spring selections will deliver up to 25 l/min with set pressures from 6-100 bar
• Gas 065 with 4 spring selections will deliver up to 900 l/min with set pressures from 6-100 bar

Application:
IMO GA valves are intended for use in oil-based systems as a safety valve or bypass valve, i.e. the valve can be used as a working valve*. The valve is adjusted to opening pressure using the spring tension and damped using the Trottle screw. During flow-through operation, the valve is thus in hydraulic balance.

*However, it is a condition that the bypass valve is not exposed to pulsating flow if it is to function as a working valve. Pulsating flow can optionally be dampened using pulsation dampeners.

Installation:
According to Manual page 2, however, close placement to pressure sensor (pump) and oil-filled pipe is recommended for safe performance. Water or chemicals are not compatible with GA valves. Water should therefore not be used as a test medium.

As a large amount of energy is deposited in the liquid through the valve, it is recommended not to bypass to the suction side of the pump, but instead back to the tank.

Please refer to technical brochure GA 1102 GB for free download.