Forge has line

I was busy soldering some copper pipe together for the gas line of the forge and something dawned upon me, something dissappointing. The melting point of the solder is only just over two hundred degrees, the forge will easily be 6-700 degrees hot at anytime whee it is switched off. And heat rises so I was afraid that the heat radiating out of the back of  the burner pipes would unsolder the joint directly above the opening of the  burner.