... ,75/8,95/8,103/4,133/8,20,or design and product according to users requirement.Flap valve ... 27/8,31/2,5,51/2We can also design and product special cement head according to users requirement ... 143/4,133/8× 171/2,16×20,20×26,etc.We can design and produce various specifications of special rigid ... 7,95/8,etc.Short joint of CasingWe can design and produce various specifications of special rigid casing ...