Based on the difference of any working condition, ZZY serires Self operated pressure regulating valve can be classified in to three types according to its inside part: ZZYP (single seat Self operated pressure regulating valve); ZZYM (cage type Self operated pressure regulating valve); ZZYN (double seat Self operated pressure regulating valve), customers can also choose the type by the local actual working condition (differential pressure, temperature, medium state) or leakage requirement. There are three different bonnet types according to the working condition: standard (normal condition), long neck type (big range for pressure adjusting), heat radiation type (temperature 350~550℃).

Self operated pressure regulating valve applies with the quick opening flow characteristic, which is quickly acted and highly accurate adjusted (error≤10%), so Self operated pressure regulating valve can be widely used in many fields like petroleum, chemical, electricity, metallurgy, food, textile, machinery and civilian building and so on to reduce/release or stabilize the pressure of the gas, steam and liquid and so on.

Self operated pressure regulating valve specification:

Self operated pressure regulating valve working principle:
1. Downstream Self operated pressure regulating valve Working principle

 

The self actuated downstream pressure regulating valve is the valve that controls the pressure at downstream and the valve action type is press-to-close type. The principle is as follows:

The medium flows through the valve body in the direction of the arrow on the valve body. The interception area between the valve plug (No.2) and the valve seat (No. 1) determines the medium flow.The controlled downstream pressure (P2) is transmitted to the sensing element via the pressure guiding tube (No.20), the condenser (No.18) (used when the medium is steam) and globe valve (No.19), and is converted into a positioning force.The positioning force adjusts the position of the valve plug according to the spring force.The spring force is adjusted by the pressure regulating disc (No.6).The fully balance valve is provided with a balance bellows (No.8), and the downstream pressure P2 acts on the inner surface of the bellows, and the upstream pressure P1 acts on the outer surface of the bellows so that the pressures P1 and P2 acting on the plug are balanced with each other.

When the downstream pressure is greater than the adjusted set point,it compresses the spring and drives the plug, and then the valve opening is proportionally reduced according to the amount of pressure change. When the downstream pressure is lower than the set point, the valve plug is driven by the reaction force generated by the spring, so that the valve opening degree is proportionally increased according to the pressure change, thereby achieving the purpose of pressure reducing and stabilizing.

2. Upstream Self operated pressure regulating valve working principle

 

The self actuated upstream pressure regulating valve is the valve that controls the pressure at upstream and the valve action type is press-to-open type. The principle is as follows:

The controlled upstream pressure (P1) is transmitted to the sensing element via the pressure guiding tube (No.20), the condenser (No.18) (used when the medium is steam) and globe valve (No.19), and is converted into a positioning force.The positioning force adjusts the position of the valve plug according to the spring force.The spring force is adjusted by the pressure regulating disc (No.6).The fully balance valve is provided with a balance bellows (No.8), and the downstream pressure P2 acts on the inner surface of the bellows, and the upstream pressure P1 acts on the outer surface of the bellows so that the pressures P1 and P2 acting on the plug are balanced with each other.

When the upstream pressure is greater than the adjusted set point,it compresses the spring and drives the plug, and the valve opens,then the valve opening increases proportionally with increasing pressure. When the upstream pressure reduces,the force acting on the detecting element is reduced. Under the reaction force of the spring, the valve plug is driven to reduce the valve opening, and the valve is closed when the pressure is lower than the pressure setting value, thereby achieving the purpose of pressure reducing and stabilizing.