Welding requirements for orbital ball valves

What device? Which one are you using? Is it welded? They are usually flanged and do not require welding.

Just like when welding ordinary ball valves, pay attention to the installation direction.

http://www.zgfqvalve.com/cn/products/otherball/bar_gdball.gif http://www.zgfqvalve.com/cn/products/otherball/cp1.gif http://www.zgfqvalve.com/cn/products/hightemball/ttt.gif Design specifications for ball valves: Design basis – GBAPI; Structural length – JB/T 7745, GB/T 12221; ANSI B16.10 for connection flanges; GB/T 9113, JB/79, HG20592; ANSI B16.5 for butt-welded ends; GB/T 12224, MSS SP44; ANSI B16.25 for testing and inspection; JB/T 9092, API 598. When it comes to welding, there isn’t much difference from other valves; the choice of welding materials and methods depends mainly on the type of material used

Why use welding? It’s usually flange connection, right? Please, the original poster, tell us

To ensure accurate fitting between the valve stem and the valve core, concentricity also needs to be taken into account.

When welding a ball valve with a track design, it is important to ensure that the valve is in the open position; if it is closed, this may result in poor sealing. The reason for this is that such valves use an eccentric design – the valve stem is raised to change the position of the ball’s center, so that the ball does not come into contact with the valve seat during operation. When the valve is closed, the ball does come into contact with the valve seat, and sealing is achieved through compression of the valve seat. If welding is carried out while the valve is closed, the heat generated during welding can be transmitted to the valve seat. Due to the tight contact between the ball and the valve seat, binding can occur, and thermal stress cannot be fully released. As a result, when the valve is opened again after being closed, the sealing surfaces do not make full contact, leading to internal leakage