Mechanical Joint Pipe
The "original" modern pipe joint, circa 1925; the mechanical joint remains in use primarily as a means for connecting fittings, valves, and similar appurtenances to a pipeline. The nuts, bolts, and gland featured in the joint provide a permanent watertight seal to 350 psi and more through a “stuffing box” compression of the gasket into its counterpart triangular recess of the joint.