Union Bonnet Needle Valves
The union bonnet needle valve is a heavy‑duty fluid control component with a robust structure and outstanding sealing performance. It adopts a specialized threaded union bonnet design, which greatly simplifies installation and daily maintenance operations.
This valve is highly adaptable to high‑pressure, high‑temperature and corrosive medium working environments, and is widely used for precision flow regulation and shut‑off control in key industries including petroleum, chemical engineering and natural gas.
Technical Parameters of Union Bonnet Needle Valve
| Parameter | Details |
| Product Type | Union Bonnet Needle Valve |
| Series 11 Max Operating Pressure | Up to 6000 psig |
| Series 11H Max Operating Pressure | Up to 10000 psig |
Maximum Operating Pressure by Series & Material
| Series | Material | Max Operating Pressure |
| Series 11 | Stainless Steel | 414 bar (6000 psig) |
| Series 11 | Alloy C‑276 | 414 bar (6000 psig) |
| Series 11 | Alloy 400 | 345 bar (5000 psig) |
| Series 11 | Titanium | 241 bar (3500 psig) |
| Series 11H | Stainless Steel | 690 bar (10000 psig) |
Main Materials of Union Bonnet Needle Valve
Standard Material: 316 stainless steel
Optional Materials: Titanium, alloy C‑276, alloy 400 and other special alloy materials (customizable upon customer request)
Structural Features of Union Bonnet Needle Valve
High‑Strength Body: Integrally forged valve body for enhanced structural stability and pressure resistance
Two‑Section Valve Stem Design: Upper valve stem threads adopt roll‑hardened treatment for wear resistance; lower valve stem surface undergoes special hardening treatment for extended service life
Anti‑Disassembly Design: Union bonnet structure effectively prevents accidental disassembly of the valve, improving operational safety
Medium Isolation: Lubricant for upper stem threads is completely isolated from system medium, avoiding medium contamination and ensuring pure fluid delivery
Non‑Rotating Lower Stem: The lower valve stem only moves up and down without rotating lifting, reducing packing wear during each stroke and minimizing friction between valve seat and valve head
Backsealing Function: Equipped with backsealing function in the fully open position, enhancing sealing reliability and protecting the stem assembly
Flexible Installation: Supports panel mounting for diversified installation scenarios
Stable Handle: Handles are locked with screws at both ends, ensuring high stability and long‑term durability; multiple handle colors are available for selection
Strict Factory Test: Each valve undergoes professional seal testing before delivery; tested with nitrogen or compressed air (for Series 34) at rated working pressure, or with water at 1.1 times the rated working pressure
