Process and installation for heat treating spheroidal or lamellar graphite cast iron pipes

An installation for effecting an annealing heat treatment of a spheroidal or lamellar graphite cast iron pipe, comprising a vessel having an elongated shape and a horizontal axis, a bath of molten metal contained in the vessel, and withdrawable means outside the bath for suspending the pipe in a substantially horizontal position and for plunging the pipe partly in the bath and simultaneously driving the pipe in rotation about the axis of the pipe, the pipe suspension and driving means comprising rotary arms which are substantially horizontal and parallel to the axis of the vessel in an operative position of the arms in which operative position the arms are located above the surface of the bath of metal contained in the vessel.

An installation for effecting a heat treatment of a metal pipe, comprising a vessel having an elongated shape and a horizontal axis and for receiving a bath of molten metal up to a given level in the vessel, and rotary means for engaging end portions of the pipe in a region of the pipe above the pipe axis for carrying and driving the pipe in rotation about the pipe axis and movable between a withdrawn first position in which position the pipe is remote from the vessel and molten metal and a second position in which second position the pipe carrying and driving means are located adjacent the vessel above said level and the pipe is partly immersed in the molten metal and said region of the pipe is located above said level with the pipe axis substantially horizontal.

An installation for effecting an annealing heat treatment of a spheroidal or lamellar graphite cast iron pipe, comprising a vessel having an elongated shape and a horizontal axis, a bath of molten metal contained in the vessel, and withdrawable means outside the bath for suspending the pipe in a substantially horizontal position and for plunging the pipe partly in the bath and simultaneously driving the pipe in rotation about the axis of the pipe, the installation further comprising an overhead crane and openable tongs carried by the crane and capable of engaging and bringing the pipe above the vessel, the tongs including pipe-supporting rollers, at least one of which rollers is provided with a driving motor.

An installation for effecting a heat treatment of a metal pipe, comprising a vessel having an elongated shape and a horizontal axis and for receiving a bath of molten metal up to a given level in the vessel, and rotary means for carrying and driving the pipe in rotation about the axis of the pipe, said means comprising rotary means for engaging end portions of the pipe on the inside of the pipe in a region of the pipe above the pipe axis, said rotary means being movable between a withdrawn first position in which position the rotary means and pipe are remote from the vessel and molten metal and a second position in which second position said rotary means are located adjacent the vessel and above said level and the pipe is partly immersed in the molten metal and said region of the pipe is located above said level and the axis of the pipe is substantially horizontal.