Abstract: A shock absorber for a wireline instrument, the shock absorber having solid, cylindrical upper body, a cylindrical sleeve, and a mandrel. The mandrel has a hexagonal upper portion, a circular center portion, and a lower nose portion. A bolt connects the mandrel to the upper body, so that the mandrel can move telescopically within the sleeve, but cannot fall out of the sleeve. Three carbide cutting elements are mounted on the sleeve adjacent to alternate sides of the upper portion of the mandrel for cutting chips of material off of the sides of the mandrel as the mandrel is moved into the sleeve.

Abstract: An improved kelly valve of a type wherein a flexible inner valve body closes the valve passageway responsive to the pressure of a gaseous control fluid contained within a sealed chamber and opens the passageway responsive to exterior pressure of drilling fluid or of tools being passed through the valve. The improvements enhance the operating life of the flexible member and simplify the valve structure and assembly and disassembly procedures.