Welding and forming method

Claim 2

A forming method in which members are force together at an interface thereof, said method comprising the steps of: placing conductors adjacent each other; placing a magnetic coil adjacent said conductors; passing a forming current through said coil to induce currents in said conductors flowing generally parallel to each other and to said interface; and said currents induced by said forming current causing said conductors to be forced towards each other in a direction generally perpendicular to said interface.

Claim 3

The method of claim 1 including the step of electrically connecting said conductors prior to passing said forming current through said coil.

Claim 4

The method of claim 1 including the step of heating the portions of said members defining said interface prior to passing said forming current through said coil and wherein said forming current causes said members to be forced together.

Claim 5

The method of claim 3 wherein said conductors define said interface and said portions are inductively heated by passing a heating current through said coil.

Claim 6

The method of claim 4 wherein said forming current causes said conductors to be welded together at said interface.

Claim 7

The method of claim 1 wherein said conductors define said interface and the skin depth of said currents induced by said forming current is not less than the thickness of one of said conductors.

Claim 8

The method of claim 1 wherein said conductors are cylindrical and define said interface and said coil surrounds the portions of said conductors defining said interface.

Claim 9

The method of claim 7 wherein at least one of said conductors is tubular and the skin depth of said currents induced by said forming current is not less than the wall thickness of said tubular conductor.

Claim 10

The method of claim 7 wherein said conductors are tubular, one of said conductors surrounds the other of said conductor thereby defining a generally cylindrical interface therebetween, and the skin depth of said currents induced by said forming current is not less than the total radial thickness of said conductors through said interface.

Claim 11

The method of claim 9 wherein the portions of said conductors defining said interface are inductively heated by passing an inductive heating current through said coil prior to passing said forming current through said coil whereby said forming current causes said conductors to be welded together at said interface.

Claim 12

The method of claim 7 wherein said conductors are cylindrical and are placed end-to-end to define an interface therebetween generally normal to the axes of said conductors.

Claim 13

The method of claim 11 wherein the portions of said conductors defining said interface are inductively heated by passing an inductive heating current through said coil prior to passing said forming current through said coil whereby said forming current causes said conductors to be welded together at said interface.

Claim 14

The method of claim 1 including the steps of: placing a pair of cylindrical conductors end-to-end to define a first interface therebetween substantially normal to the axes of said conductors; placing a conductive sleeve In position surrounding the portions of said cylindrical conductors defining said first interface to define a second interface between said sleeve and one of said conductors and a third interface between said sleeve and the other of said conductors; placing said magnetic coil in position adjacent and generally surrounding said interfaces; passing said forming current through said coil to induce currents in said conductors and said sleeve flowing generally parallel to each other and to said interfaces; and said currents causing said conductors to be forced together in a generally axial direction and said conductors and said sleeve to be forced together in generally radial directions.

Claim 15

The method of claim 13 wherein the portions of said sleeve and said conductors defining said interfaces are heated prior to passing said forming current through said coil.

Claim 16

The method of claim 14 wherein said portions are heated by passing an inductive heating current through said coil.

Claim 17

The method of claim 13 wherein the skin depth of said currents induced by said forming current is not less than the radial thickness of said sleeve.

Claim 18

The method of claim 13 wherein said conductors are tubular and the skin depth of said currents induced by said forming current is not less than the total radial thickness of one of said conductors and said sleeve through the interface defined thereby.

Claim 19

The method of claim 17 wherein the portions of said conductors and said sleeve defining said interfaces are heated prior to passing said forming current through said coil.

Claim 20

The method of claim 4 including the step of cooling surfaces of said conductors during the inductive heating thereof.

Claim 21

The method of claim 4 including the steps of inductively heating said conductors and then forcing said conductors together by inducing parallel-flowing currents therein subsequent to the initial inductive heating and forcing together of said conductors.