Rigid pipe connector with radially shiftable lock elements and method of making the same

A rigid pipe connector comprising:

• a pin and a box;
• said pin having an externally tapered section and a transverse make up shoulder;
• said box having an internally tapered body section to receive the tapered section of said pin and having an open end and an inner transverse make up shoulder confronting said pin make up shoulder;
• said pin section and said box section having therebetween axially spaced companion tapered sealing portions;
• said box section having port means between said sealing portions for admission therebetween of a pressure fluid acting to circumferentially expand said box section and compress said pin section;
• and means on said pin and box engageable by a loading tool for axially relatively forcing said sections and compressively loading said make up shoulders while said pressure fluid is acting on said sections;
• said pin and box sections being held against axial separation with said make up shoulders in compression and said box section in tension by a pressure energized shrink fit between said pin section and said box section upon relief of said pressure fluid;
• and locking means coacting between said pin and box to hold said pin in compression and said box in tension, said locking means comprising circumferentially spaced locking elements projecting radially from one of said pin and box and lockingly engaged with the other of said pin and box.