1. Fittings used for connecting pipes include: flanges, unions, pipe clamps, band clamps, couplings, and hose clamps, etc.

2. Fittings for changing pipe direction: elbows, bends

3. Fittings for changing pipe diameters: Reducing (Reduced) Tee, Reducing Elbow, Branching Tee, Reinforcing Pipe

4. Pipe fittings for branch lines: Tees, Crosses

5. Pipeline sealing fittings: gaskets, plumber's tape, hemp rope, flange blind plate, pipe plug, blind flange, cap, and welding plug

6. Pipeline fixing fittings: clamps, shackles, eye bolts, brackets, supports, pipe clips, etc.