Alloy Check valve Manufacturer in Saudi Arebia
The pressure seal gate valves supplied by Metals Valve are mainly used in high temperature & high pressure applications such as power-plant steam service. The pressure sealed bonnet-body joint is a more positive way of sealing compared to its bolted bonnet counterparts because the internal pressure of the valve is used for bonnet sealing. As the line pressure is elevated, the load between the sealing surface of bonnet and tapered gasket tends to be increased – the higher the line pressure(valve internal pressure), the greater the sealing force against the bonnet gasket. Hence a more effective sealing can be achieved. Metals Valve’s pressure sealed gate valves are available in cast/forged carbon steel, alloy steel, or stainless steel materials furnished with end connections of butt welding(BW), socket welding(SW) and flanged(RF/RTJ). They are designed as per API 600 and ASME B16.34 covering pressure ratings of Class 600, Class 900, Class 1500, Class 2500. Alloy Check valve
As illustrated in Fig-1, the pressure sealed bonnet-body joint of a high pressure gate valve is constructed by proper arrangement of body, bonnet, metallic gasket, seal ring, segmental thrust ring, retainer, body cover and a couple of bolts & nuts. The lower end of the bonnet is outwardly sloped to form a sealing contact with the inverted frusto-conical surface of the metallic gasket. The metallic gasket, usually made of soft steel material, is held down by a segmented thrust ring which is inserted into the annular groove of the valve body. The words “segmented” or “segmental” refer to the thrust ring consisting of a plurality of segments all of which may be cut from a single ring. A seal ring made of hard metal is placed between the thrust ring and the gasket and serves to distribute pressure on the thrust ring the gasket preventing deformation of the top surface of the relatively soft gasket. Both the metallic gasket and the seal ring shall be furnished with spaced threaded holes for ease of removing and maintenance. Besides, A – There shall be a 1° angle between mating surfaces of the bonnet slope and the gasket slope. This wedged design ensures a tight seal at either low or high line pressure. B – The interior sealing surface at the body neck shall be welded with a stainless steel inlay to provide finer grain and smooth finish as well as better corrosion resistance. C – Radial bores are furnished in the valve body through which a knock-out pin may be inserted for driving the segmental rings out of the groove. D – A small end bevel on the gasket to prevent it from scraping or catching in the
3. Material Selection
- C.S & S.S & Low Temp.
- High Temperature Alloy Steel
1. Conventional carbon steel, stainless steel, and low-temp materials for pressure seal gate valves.
2. Body materials listed in this table are cast steel. Forged steel body can be provided upon request.
3. Bonnet materials are furnished in forged steel to provide finer grain structure for a tight seal.
4. For sizes 4″ and smaller, the bonnet gasket shall be made of graphite.