Introduction
The pneumatic quick piston shut-off valve (hereinafter referred to as the piston shut-off valve) is a special shut-off valve designed for rapid cut-off or switching operations. It can change the cut-off and flow direction of the medium in as fast as approximately 0.2 seconds in response to signals from control instruments. This product features high operating force, low flow resistance, increased rated flow coefficient, and excellent sealing performance. Therefore, it is widely used in the automatic control of cooling water switches and switching in the production processes of high-speed wire rods, bars, etc.
-
under high-frequency switching and high-speed impacts.
-
The valve stem of this pneumatic quick shut-off valve is twice the diameter of a standard shut-off valve. After undergoing special hardening treatment, it is precision-machined through primary processing and then ground to a high surface finish on a grinding machine. This ensures long-term reliable sealing even under the harsh conditions of high-speed movement.
-
The pneumatic actuator is the key to the rapid response of the shut-off valve. Comprising specialized solenoid valves and accessories, it can complete valve opening or closing operations in approximately 0.2 seconds.
-
The shut-off valve exclusively uses expensive sealing packing imported from the United States. With superior flexibility, wear resistance, and sealing performance compared to domestically produced alternatives, it ensures efficient sealing between the valve bonnet and the valve stem.
Technical Parameter
Standard Specification - Body Part
| Type | Unbalanced plug type (ZSKP), Balanced plug type (ZSKM, ZSKG) |
|---|---|
| Nominal diameter | DN25mm~300mm (1"~12") |
| Flow characteristic | Quick opening |
| Trim material and treatment | For standard material combinations, temperature · pressure range and leakage class, refer to Table 1 and Figure 1. |
| Nominal pressure |
PN series: PN1.6MPa, 2.5MPa, 4.0MPa, 6.3MPa, 10.0MPa Class series: Class150, 300, 600 |
| Connection method | Flanged, Welded① |
| Flange distance | Complies with GB12221 |
| Body and bonnet material | WCB, CF8, CF8M, CF3, CF3M② |
| Actuator | Double-acting piston type |
| Packing | PTFE V-ring packing, PTFE carbon fiber, PTFE asbestos and flexible graphite |
| Surface coating | Light camel color, stainless steel body is not painted. |
|
Note ①: Connection method, body flange and flange face distance can be manufactured according to the standards specified by the user. ②: Body, bonnet and trim materials can be manufactured according to the standards specified by the user. |
|
Valve Installation & Maintenance
Valve Installation:
(1) Before installation, check that the product model, tag number, and specifications match the requirements. Inspect the entire valve for missing or loose parts.
(2) Prior to installation, clean the pipeline. Ensure there is sufficient straight pipe section at the valve inlet and install a filter. When connecting the valve body to the pipeline flanges, ensure coaxiality.
(3) Thoroughly clean the pipeline before installing the valve.
(4) The installation site should ensure the safety of personnel and equipment, facilitating operation, disassembly, and maintenance.
(5) The valve should be installed vertically upright on horizontal pipelines. If necessary, it can be installed at an angle, but horizontal installation should be avoided. For occasions with heavy valve weight or vibration, use a support frame.
(6) The medium flow direction must align with the arrow on the valve body. The air supply should be dry and oil-free. The valve should be used in environments with temperatures ranging from -20℃ to 55℃.
(1) Before installation, check that the product model, tag number, and specifications match the requirements. Inspect the entire valve for missing or loose parts.
(2) Prior to installation, clean the pipeline. Ensure there is sufficient straight pipe section at the valve inlet and install a filter. When connecting the valve body to the pipeline flanges, ensure coaxiality.
(3) Thoroughly clean the pipeline before installing the valve.
(4) The installation site should ensure the safety of personnel and equipment, facilitating operation, disassembly, and maintenance.
(5) The valve should be installed vertically upright on horizontal pipelines. If necessary, it can be installed at an angle, but horizontal installation should be avoided. For occasions with heavy valve weight or vibration, use a support frame.
(6) The medium flow direction must align with the arrow on the valve body. The air supply should be dry and oil-free. The valve should be used in environments with temperatures ranging from -20℃ to 55℃.
Valve Maintenance:
(1) Cleaning the Valve: For general media, cleaning with water is sufficient. For media harmful to health, first understand their properties and then select an appropriate cleaning method.
(2) Disassembly: Remove rust from exposed rusted parts first. Before derusting, protect the machined surfaces of precision parts such as the valve seat, valve plug, valve stem, and push rod. Use special tools when disassembling the valve seat.
(3) Valve Seat: Minor rust or wear on the sealing surface can be repaired by machining. If damage is severe, replace the seat. However, both repaired and replaced hard sealing surfaces must be lapped.
(4) Valve Stem: If the surface is damaged, it must be replaced.
(5) Damage to Push Rod, Guide, and Sealing Surfaces: Reverse-acting actuators must be replaced; direct-acting actuators can be reused after proper repair.
(6) Compression Spring: If there are cracks or other defects affecting strength, replace it immediately.
(7) Wear Parts: Packing, gaskets, and O-rings must be replaced entirely during each maintenance. Check the valve plug and diaphragm for cracks, aging, or corrosion that may cause future failures. Decide whether to replace them based on inspection results, but the diaphragm service life should not exceed 2-3 years.
(8) When reassembling the valve, ensure alignment. Tighten bolts diagonally and lubricate sliding parts. After reassembly, debug the valve according to the factory test items and methods. During this period, accurately adjust the packing compression force and the valve plug closing position.
(1) Cleaning the Valve: For general media, cleaning with water is sufficient. For media harmful to health, first understand their properties and then select an appropriate cleaning method.
(2) Disassembly: Remove rust from exposed rusted parts first. Before derusting, protect the machined surfaces of precision parts such as the valve seat, valve plug, valve stem, and push rod. Use special tools when disassembling the valve seat.
(3) Valve Seat: Minor rust or wear on the sealing surface can be repaired by machining. If damage is severe, replace the seat. However, both repaired and replaced hard sealing surfaces must be lapped.
(4) Valve Stem: If the surface is damaged, it must be replaced.
(5) Damage to Push Rod, Guide, and Sealing Surfaces: Reverse-acting actuators must be replaced; direct-acting actuators can be reused after proper repair.
(6) Compression Spring: If there are cracks or other defects affecting strength, replace it immediately.
(7) Wear Parts: Packing, gaskets, and O-rings must be replaced entirely during each maintenance. Check the valve plug and diaphragm for cracks, aging, or corrosion that may cause future failures. Decide whether to replace them based on inspection results, but the diaphragm service life should not exceed 2-3 years.
(8) When reassembling the valve, ensure alignment. Tighten bolts diagonally and lubricate sliding parts. After reassembly, debug the valve according to the factory test items and methods. During this period, accurately adjust the packing compression force and the valve plug closing position.
Ordering Instructions
When placing an order, please fill in the Specification Sheet or specify the following information:
-
If the model has not been selected before ordering, please provide us with the operating parameters:
(1) Nominal diameter DN (mm);
(2) Nominal pressure (MPa or bar);
(3) Fluid properties (including medium temperature, viscosity, or acidity/alkalinity);
(4) Pressure before and after the valve (pressure differential);
(5) Requirements for flow characteristics;
(6) Materials of valve body and valve core;
(7) Connection type;
(8) Driving method (provide air supply pressure, driving voltage);
(9) Supporting accessories (for pneumatic valves, it is recommended that users install an air filter triplet and a 2-position 5-way solenoid valve);
(10) On-site working conditions. -
If the product model of our company has been selected by the design unit, please order directly from our production department according to the model;
-
When the application occasion is very important or the pipeline is relatively complex, please provide the design drawings and detailed parameters as much as possible, and our experts will review and check them for you.
