G-valves DN25–800 for oil, fresh water/glycol or salt water
ACV valves are 3-way temperature control valves consisting of a powerful rotary valve and a quarter turn EL or PNEU actuator. High accuracy providing better temperature control. Can be used as a mixing or diverting application.
Ing Westad AS offers a wide range of actuators that meet the most demanding specifications, including explosion-proof, fail safe (EL + pneu), high duty cicel, extra protective surface treatment, including NORSOK. Furthermore, a wide range of EL as well as control signals such as analogue, digital and bus communication.The powerful rotor design provides tight temperature control without high maintenance claim. The system is available in three standard control configurations: EL, PNEU, and electro-pneumatic, offers flexibility for most requirements.
Some actuator options are designed and reinforced for vibration service and is qualified to Lloyd;s Marine Requirements for ship service. Standard G valves are suitable for a range liquids such as water, water/glycol, seawater, lubricating and hydraulic oils. Optional body material is available for services involving synthetic or fireproof oils, deionized water and ammonia or freon in oil.
Key features and benefits
1. Lightweight and compact
2. Configurable ports - allowing flexibility on installation
3. Low pressure drop - enables savings on either valve or pump size
4. High accuracy providing better temperature control
5. Can be used as a mixing or diverting application.
6. Can regulate cooling of hot systems (e.g. engine) or heat to cold systems (e.g. LNG).
7. Can switch between 2 or more setpoints during operation.
8. Can sense the temperature in a circuit with air, oil and water and control the temperature of coolant oil or water.
Applications
Mixing Applications
Lubricating oil temperature control is normally configured in a mixing application controlling the return temperature to the heat load. The temperature is normally measured as close as possible to the sump return.
Diverting Applications
Jacket water cooling in diverting applications regulates the outlet coolant water temperature from a diesel or gas engine. The valve either sends water to a cooler or bypass loop, accurately maintaining the temperature. The temperature is normally measured at the outlet from the heat source.
Charge Air Temperature Control
The intercooler is used to cool high temperature turbo charger air. In this application the G Valve regulates the flow of cooling water through an intercooler, increasing efficiency, enhancing performance and helping to meet today’s environmental requirements.
Electric Valve – GG and GEF
For the electric valve, the actuator of the G valve assembly uses an electric motor which rotates in either direction in response to the ON-OFF signals received. The motor drives a gearbox connected to the rotor shaft and turns the valve rotor clockwise or counter-clockwise, a maximum of 90 degrees. At the end of travel, limit switches are incorporated to isolate the electrical supply to the motor when the valve rotor has reached either end of the rotation. A feedback hall sensor is standard and provides position indication to the control system. The electric actuator is a rugged, compact and lightweight quarter turn actuator having enclosure protection to IP65. The actuator is powered by an electric motor driving a worm-type gearbox. The worm gearbox prevents reverse drive due to fluid forces. It is fitted with manual override as standard, enabling valve operation without power. A thermal cutout is fitted preventing overheating. Limit switches at each end of stroke disconnect motor power when end stroke is reached. These can also be used for remote indication.
Pneumatic Valve – GG and GPD
The pneumatic valve uses a spring return pneumatic actuator and positioner to control the rotation of the valve in response to an input signal from a pneumatic or electro-pneumatic control system. The pneumatic control system sends a pneumatic signal ranging from 0.21 to 1.03 bar (3 to 15 psi) to the actuator to correctly position the valve at the desired temperature setting. The pneumatic control system usually consists of a P+I pneumatic controller, sensor and the necessary air supply conditioning equipment (regulators, filters and water traps). The actuator is fitted with spring return as standard allowing fail-safe configuration if necessary. It is also fitted with a valve positioner enabling accurate and repeatable movement.
Modes of Operation
The unique construction of the AMOT G valve provides total flexibility by allowing you to select the valve port positions most ideally suited to meet your application requirements. There are two main types of mode of operation: 90° rotor that allows either ports 1 or 3 to be selected as the common port; and 180° rotor that requires port 2 to be the common port. Arrow indicates valve movement with increasing temperature or mA, as viewed from above (see diagram). For electrically actuated valves, on loss of signal the actuator is set up by default to stop in its current position.
