Frac Valves - ball screw gate valve is a type of large bore gate ... . Phosphating for improve corrosion resistance. 1.FEATURES: Valve with Ball Screw Ball screw structure lowers operating time Gate valve design Stem structure ... /16” ●Working Temperature: K, L, P, R, S, T, U, V ●Material Class :AA, BB, CC, DD, EE, FF, HH ●Specification ...