WELDING APPARATUS

PROBLEM TO BE SOLVED: To provide a welding apparatus which materializes a stable welding state by performing more even heating by means of further structural working even while following a heater part of a simple structure having a pair of halved heaters and is improved so as to make an insulating material unnecessary and so as to permit maintenance-free operation.SOLUTION: The welding apparatus has the heater part 3 which externally surrounds a joint part S made by fitting a pipe end part 4 of a welding coupling T made of PFA and an end part 6 of a tube 5 made of PFA and welds the tube end part 4 with the end part 6 by thermally welding the joint part S with heat generation of the heater part 3, wherein the heater part 3 has an annular structure formed by arranging a pair of halved heaters h each having a substantially semi-circular inner peripheral surface 7 for heating the joint part, and the halved heater h has a heat transfer case 9 assuming a substantially semi-circular shape, made of ceramic and a heat generation element 10 which is conductively connected to the outside on one end part in the circumferential direction of the heat transfer case 9 and is housed in a folded state on the other end in the circumferential direction.