The forged steel bellows globe valve has three bonnet design forms: the first is a bolted bonnet. The valve designed according to this design has a valve body connected to the bonnet with a bolt and nut. The winding type product features: 316 clamp flexible graphite) seal, customers can also use metal rings to connect when special requirements. The second design form is a welded bonnet. According to this design, the valve body and the bonnet are threaded and fully welded. If the customer has special requirements, a through-weld connection can also be used. The third type is a self-sealing bonnet. A valve designed according to this design has a threaded connection between the valve body and the bonnet, and an internal pressure self-tight ring seal.
Features: The valve stem is sealed with a corrugated tube, using a filler-assisted seal, a double-layer corrugated tube, no lifting handwheel, and a valve stem anti-rotation device.
Application: Industrial, power system, exhaust gas purification device, gas, steam equipment, vacuum equipment, hot water, heat transfer oil application, shipbuilding industry, etc.
Applicable medium: petroleum, natural gas, steam, hot water, heat transfer oil, industrial water, etc.
Gate valve design structure and characteristics:
Gate valves are designed and manufactured in accordance with API602 and ASME B16.34. Inspection and testing shall be in accordance with API 598, and the marking shall be in accordance with MSS-SP-25.
With the following structure
Full or reduced diameter
Open pole bracket type (OS & Y)
Self-centering plate pressure sleeve
Bolt connection, wound gasket sealed bonnet, nut connection, fully welded sealed bonnet and threaded connection internal pressure self-tightening bonnet
Integral upper seal seat
Socket end complies with ASME B16.11
Threaded end (NPT) meets ANSI / ASME B1.20.1
Forged steel valves have the following advantages:
1. Small flow resistance. The medium channel inside the valve body is straight through, the medium flows in a straight line, and the flow resistance is small;
2. Less effort when opening and closing. Compared with the shut-off valve, whether it is open or closed, the movement direction of the gate is perpendicular to the medium flow direction;
3, high height, long opening and closing time. The opening and closing stroke of the gate is large, and the lowering is performed by the screw;
4, water hammer phenomenon is not easy to produce. The reason is the long closing time;
5. The medium can flow in any direction on both sides, which is easy to install. Gate valve channels are symmetrical on both sides;
6, the structure length (the distance between the two connecting end faces of the shell) is small;
7, the sealing surface is easy to wear, affecting the service life. During opening and closing, the two sealing surfaces of the gate and the valve seat frictionally slide with each other. It is easy to cause abrasion and wear under the effect of medium pressure, which affects the sealing performance and shortens the service life.
8. The price is more expensive. There are more contact sealing surfaces, and the processing is more complicated, especially the sealing surface on the gate seat is not easy to process, and there are many parts. Simple shape, short structure length, good manufacturing process and wide application range.