Introduction
This shut-off valve receives signals from control instruments to cut off, open, or redirect the flow of media, enabling automatic control of process parameters such as pressure, flow rate, temperature, or liquid level. It is widely used in the automatic control and remote control systems of various industrial sectors including petroleum, chemical, metallurgy, power, light industry, and textiles.
Product Specifications:
- Actuator Types: Diaphragm and piston
- Body Structures: Single-seated, cage-guided, double-seated (two-position three-way)
- Sealing Options: Packing seal and bellows seal
- Nominal Pressure Ratings: PN10, 16, 40, 64
- Nominal Diameter Range: DN20 to 200 mm
- Temperature Range: -60°C to 450°C
- Leakage Class: IV or VI
- Flow Characteristic: Quick opening
- The shut-off valve employs a multi-spring actuator connected to the regulating mechanism by three columns, reducing the overall height by approximately 30% and weight by about 30%.
- The valve body is designed with an equal-section, low-flow-resistance channel based on fluid dynamics principles, increasing the rated flow coefficient by 30%.
- The sealing components inside the valve are available in two types: a tight-sealing type with hard alloy overlay welding and a soft-sealing type made of soft materials, both providing excellent sealing performance when closed.
- The balanced valve internals enhance the allowable pressure differential of the shut-off valve.
- A bellows seal provides complete sealing for the moving valve stem, eliminating the possibility of medium leakage.
- The piston actuator offers high operating force and is suitable for high-pressure-differential applications.
Technical Parameter
Main part materials of ZXQ(ZSQ) pneumatic shut-off valve
| Valve body, sealing sleeve: | HT200, ZG230-450, ZG1Cr18Ni9Ti, ZG0Cr18Ni12Mo2Ti |
|---|---|
| Valve core, valve seat: | 1Cr18Ni9Ti, 0Cr18Ni12Mo2Ti, 1Cr18Ni9Ti overlaid with Stellite alloy |
| Sleeve, valve plug: | 1Cr18Ni9Ti, 0Cr18Ni12Mo2Ti, 1Cr18N19Ti overlaid with Stellite alloy |
| Packing: | Polytetrafluoroethylene, flexible graphite |
| Corrugated diaphragm: | Nitrile rubber reinforced with polyester fabric |
| Spring: | 60Si2Mn |
| Push rod, valve stem: | 2Cr13, 1Cr18Ni9Ti |
| Valve core, valve plug (soft parts): | Reinforced polytetrafluoroethylene |
| Bellows: | 1Cr18Ni9Ti |
Main technical parameters and performance indicators of ZXQ(ZSQ) pneumatic shut-off valve
| Nominal diameter DN (mm) | 15 | 20 | 25 | 32 | 40 | 50 | 65 | 80 | 100 | 125 | 150 | 200 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Rated flow coefficient Kv | Single-seat, double-seat | 5 | 7 | 11 | 20 | 30 | 48 | 75 | 120 | 190 | 300 | 480 | 760 |
| Sleeve |
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11 | 20 | 30 | 48 | 75 | 120 | 190 | 300 | 480 | 760 | |
| Nominal pressure PN (MPa) | 1.0 1.6 4.0 6.4 | ||||||||||||
| Rated stroke (mm) | 8 | 12 | 20 | 25 | 40 | 50 | |||||||
| Effective area (cm2) | ZMQ type | 100 | 200 | 400 | 600 | 1000 | |||||||
| ZSQ type | 100 | 125 | 160 | 250 | |||||||||
| Allowable leakage | Hard seal l/h |
General: 10-4 × valve rated capacity; |
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| Soft seal | Class VI | ||||||||||||
| Allowable differential pressure (MPa) | ZMQP (N) direct action | 6.4 | 5.09 | 2.91 | 1.85 | 2.18 | 1.33 | 1.52 | 0.99 | 0.62 | 0.60 | 0.69 | 0.39 |
| ZMQP (N) reverse action | 6.4 | 6.4 | 3.88 | 2.47 | 2.91 | 1.77 | 2.03 | 1.32 | 0.83 | 0.80 | 0.92 | 0.52 | |
| ZSQP (N) | 6.4 | 6.1 | 3.5 | 2.3 | 3.0 | 1.9 | 1.9 | 1.5 | 0.93 | 0.84 | 0.65 | 0.47 | |
| ZM (N) QM | Nominal pressure | ||||||||||||
| Signal pressure (kPa) | ZMQ | 0 or 250 | |||||||||||
| ZSQ | 0 or 400 - 600 | ||||||||||||
1) The performance indicators of this product comply with the GB/T4213-92 standard;
2) If the allowable differential pressure value in the table is greater than the nominal pressure, the nominal pressure value shall be taken; if it is less than or equal to the nominal pressure value, it remains unchanged;
3) The allowable values in the table are for standard cylinders. Different cylinders can be used to increase the allowable differential pressure.
Selection of valve body and valve core materials for ZXQ(ZSQ) pneumatic shut-off valve
| Nominal diameter | 15 | 20 | 25 | 32 | 40 | 50 | 65 | 80 | 100 | 125 | 150 | 200 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| A | Ф196 | Ф232 | Ф308 | Ф394 | Ф498 | ||||||||
| L | PN16, 40 | 130 | 150 | 160 | 180 | 200 | 230 | 290 | 310 | 350 | 400 | 480 | 600 |
| PN64 | 210 | 230 | 230 | 260 | 260 | 300 | 340 | 380 | 430 | 500 | 550 | 650 | |
| H | PN16, 40 | 305 | 340 | 345 | 370 | 380 | 390 | 475 | 490 | 500 | 765 | 825 | 927 |
| PN64 | 320 | 350 | 354 | 372 | 382 | 397 | 473 | 475 | 517 | 805 | 882 | 815 | |
| Bellows seal type | 375 | 409 | 414 | 431 | 441 | 468 | 555 | 570 | 613 | 855 | 915 | 1017 | |
| H1 | PN16, 40 | 50 | 53 | 58 | 70 | 75 | 83 | 93 | 100 | 110 | 125 | 143 | 170 |
| PN64 | 60 | 65 | 70 | 77.5 | 85 | 90 | 100 | 85 | 125 | 148 | 170 | 208 | |
| H2 | PN16 | 115 | 115 | 121 | 130 | 140 | 153 | 178 | 190 | 200 | 260 | 320 | 360 |
| PN40 | 125 | 125 | 130 | 140 | 150 | 160 | 185 | 200 | 220 | 280 | 320 | 380 | |
| PN64 | 150 | 150 | 160 | 170 | 180 | 200 | 230 | 250 | 282 | 310 | 430 | 480 | |
| H3 | PN16, 40 | 404 | 415 | 428 | 448 | 448 | 468 | 561 | 578 | 590 | 886 | 1008 | 1120 |
| PN64 | 365 | 430 | 498 | 528 | 528 | 530 | 535 | 540 | 600 | 890 | 1208 | 1305 | |
| Bellows seal type | 395 | 465 | 478 | 509 | 509 | 548 | 641 | 658 | 670 | 976 | 1098 | 1210 | |
| Weight kg | Standard type | 10 | 10 | 12 | 15 | 18 | 23 | 35 | 45 | 60 | 75 | 90 | 120 |
| Bellows seal type | 12 | 12 | 14 | 17 | 20 | 26 | 38 | 48 | 64 | 79 | 95 | 125 | |
Connection dimensions and standards of ZXQ(ZSQ) pneumatic shut-off valve
• Flange standard: Cast iron flanges comply with GB4216-84, steel flanges comply with GB9113-88, JB/T79-94
• Flange sealing surface type: Convex surface for PN10, PN16; Concavo-convex surface for PN40, PN64, with the valve body having a concave surface.
• Structural length: Complies with the GB12221-89 standard
• Actuator air signal interface: Internal thread M10×1
﹡ The valve body flanges and flange face distances can be manufactured according to user-specified standards, such as ANSI, JIS, DIN, etc.
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:
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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;
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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.
