m         =          4 mm

n          =          12 mm

CH       =          14 mm for 20SD

                        18 mm for 25SD

                        22 mm for 30SD

                        28 mm for 35SD

                        32mm for 40SD

           

Pipe Thk. tolerance (-10%)

A-Class = 3.6 mm

B-Class = 4.8 mm

C-Class = 5.4 mm