... than 15 years experience about making double ball valve moulds.union ball valve has seven parts.We can make all kinds ... clear communications.2. We can provide various of single/double Union valves, check valves, membrane valves, bottom valves, gate valves, locking ... , coupling, tee, reduce, cap, union, flange, flexible connector, water supply and sewerage pipe fitting moulds, etc. made of ABS, U-PVC, C ...