초록 ▼

A method of welding using a preheating insert is disclosed. The method includes the steps of positioning and igniting a combustible solid fuel mixture within a pipe to preheat the pipe by convection to a proper temperature and welding the pipe. The preferred and illustrated embodiment incorporates a

A method of welding using a preheating insert is disclosed. The method includes the steps of positioning and igniting a combustible solid fuel mixture within a pipe to preheat the pipe by convection to a proper temperature and welding the pipe. The preferred and illustrated embodiment incorporates an encircling bottom support having a centralized hollow tube. It is made of a frangible material to be easily broken should it fall into the pipe. It supports a hollow, cylindrical, combustible heating element. The heating element is made of thermite as an example. It includes a top located deflector plate to deflect hot gases flowing upwardly from combustion against the wall of a pipe to be heated. The apparatus is concentrically located within the pipe in the vicinity of the pipe section to be heated.

대표청구항 ▼

The method of welding a pipe by preheating a pipe section thereof, comprising the steps of: (a) igniting a combustible solid fuel mixture supported within the pipe; (b) positioning the solid fuel mixture within the pipe opposite the pipe section where a weld bead is to be formed; (c) heating the pip

The method of welding a pipe by preheating a pipe section thereof, comprising the steps of: (a) igniting a combustible solid fuel mixture supported within the pipe; (b) positioning the solid fuel mixture within the pipe opposite the pipe section where a weld bead is to be formed; (c) heating the pipe section by convection to an elevated temperature by directing heated gases given off by the ignited fuel mixture against the pipe section; (d) monitoring the temperature of the pipe section to determine that the pipe section has been heated to a specified temperature; and (e) welding the pipe by forming a multi-pass bead.