The impulse piping is the one which connects the process outputs to the transmitter.

To protect the Pressure, Vacuum or, DP Instruments from the higher temperature, we provide Impulse Tubes, which is also called as Capillary Tubes. The Instrument should be installed at one end of the Impulse Tube, ensuring that there are no any leakages at that end, and the other end of the impulse tube should be connected to the process. 

These tubing can be in Copper or, SS construction, depending up on the material suitability for the process fluid.