Four-way switch valves

Features and benefits

• A Lantern ring with steam block and extra deep stuffing box minimizes the risk of leakage occurring through the packing chamber. Live-loading is available on request.
• The sturdy one-piece ball and stem provides optimal strength, and is well suited to applications where fouling due to coke fines are a concern. The one-piece design avoids the problems generally associated with the more conventional two-piece ball and stem, which is highly susceptible to solids buildup in the ball-stem joint and a resulting increase in operating torques.
• Strong bellows offer a unique seat loading design that maintains the floating seats in constant contact with the ball and ensures a positive seal.
• Scraper type seats: Velan’s unique seat design scrapes coke buildup from the surface of the ball during each cycle. Seats are hard-faced to ensure a long, trouble-free service life. 
• Steam purges to bellows and body area ensure the valve cavities are kept free of coke buildup.