... and double groove pipe, tube frame 1. Roller and mould for round pipe, square pipe, shaped pipe, etc. 2. ... shaped tube, polygonal tube, single and double groove pipe, tube frame, special-shaped mould, etc.3. ... 60-63HRC.8. Selection: To produce first-class pipe mould, we must have first-class raw material. ... concave angle phenomena, and to form tolerance of roundness in les than 0.05mm, square tube on ...