Boiler Feed Water Valve Fail Position

Boiler feedwater is treated to protect it from two basic problems.

Boiler feed water valve fail position.

It is critical not to allow the hrsg to dry out which can cause severe thermal damage to the boiler tubes and the drums. The feedwater valves are normally sized to accommodate an operating condition that occurs when the safety valves open during a unit trip. One important parameter of their design is the pressure drop at the rated condition as well as off design conditions. The valve s fail position is a safety precaution that protects your process in emergency situations.

Some typical applications are 0 135 ohm slide wires from a mcdonnell and miller 7b switch or a 4 20ma signal from a. N failure mode fail safe is the preferred failure mode which. Modulating feedwater valves allow for constant incremental adjustments to feed water into your boiler. Be a boiler feedwater regulator valve where a constant speed feed pump is used.

Coupling dependable service with added protection into one quality product is taco s combination boiler feed backflow preventer valve. To protect against this the feedwater valves are sized for minimal pressure. They come in all types from ball valves to knife gates to globe valves and operate. Large and sudden change in steam load and or.

Feedwater control valves play a critical role in boiler operation. Taco boiler feed valves have set the standard for dependable service. Drum level controller inadvertently left in manual position. There are a few different fail scenarios.

Safety valve lifting and then reseating. Off of many types of signals. Loss of water to the deaerator or makeup water system. The buildup of solid deposits on the interior or water side of the tubes and corrosion.

Loss of plant air pressure to the control valve actuator. The backflow preventer offers added protection preventing the system from emptying if supply pressure should fail. The pressure condition for the valve inlet pump. Drum level controller failure.

Each having its own consequences and safety effects.