Penstock may consist of a single line and by the number of parallel lines and turbine HPP design. Starting as a single line from the open water surface penstock connected to more than one turbine is divided into arms of the central entrance. this separation of the "branch or pants zone" is called.
Penstock and selected outlets in the calculation result, the appropriate thickness and strength of the steel sheet metal bending and straight seam welded construction or ready spiral welded pipe is manufactured with welded joining again.
Penstock basically can be divided into two types:
1- Exposed Penstock
2- Buried Penstock