with high thrust capacity and self alignment properties is mounted on a stub shaft integral with the head piece and enclosed by a shell body associated with the tail piece a gap between the head piece and shell body is sealed with a metal face seal assembly a juncture between the shaft and main part of the head piece is shaped to avoid a stress riser condition and a thrust washer has a configuration complimentary to the juncture to transmit forces between the head piece and bearing assembly a joint between the tail piece and shell body is locked with a weld bead technique that enables the unit to be refurbished with reduced labor application_number US 94356701 A description referring now to the figures there is shown a swivel assembly 10 for coupling a drill or pipe string to a product such as a communications cable power cable or conduit for the same typically a pipe string will be positioned in a bore or hole with horizontal directional drilling techniques at the down hole end of the drill string the swivel can be connected between the drill string and the lead end of a product to enable it to pull the product back through the bore the swivel 10 includes a head piece 11 a shell body 12 and a tail piece 13 which are primarily round bodies that in assembly are all concentric with a common axis 14 disposed within these bodies are a seal assembly 16 a thrust.