DOYLES carries a large inventory of Type U ram blocks to fit a wide variety of tubing, drill pipe, and casing sizes. All rams are suitable for H₂S and meet NACE specifications. Variable Bore Rams can be used to seal on a range of pipe sizes. We carry both large and small bore. Shear rams cut the pipe in the hole, and bend the lower section of pipe to close off the rams and seal. Shear rams can also be used as blind rams during normal drilling applications.