catalytic converter air tubes?

I own a 1988 f250 automatic 2 wheel drive with a 351 V8. on the top of catalytic converter there are to 1 inch diameter air tubes. The one closest to the engine is plugged with a screw and the other has a metal pipe going from it back towards the motor. The pipe is broken at the top where the pipe and air tube connect. What is this pipe for? The break is jagged and corroded how do I repair this? Is there any heat resistant rubber tubing that can be used to clamp on?


Thank you