Machining of grooves

SAB gorge

Recommendations for the calculation and machining of piston grooves for hydraulic applications.
Diameter from 18 to 200 mm, all rings except those on which the surfaces are not parallel.

SABexe_g01
SABexe_g02

In case of bilateral thrust, both groove surfaces will require precision grinding: Ra ≤ 0.8nm

Cylinder bore……………………..D = d1, tolerance H7 (d1: nominal ring Ø)
Piston diameter …………………d = d1, tolerance f8
Groove base gap…………………z : according to d1, see chart P1
Groove base diameter…………dL = d min – (2.a1 max + z)
Tolerance on dL…………………-0.00 / -0.20 mm
Groove width……………………..L = h1, tolerance, see chart P
Groove base radius……………..R : according to dl, see chart PI

Table P
Tolérance on L Pressure
Laterales Bilaterales
Tolérance C9 Tolérance F8
Table P1
Z R
dl > 100 mm 0.80 0.50
dl ≤ 100 mm 0.50 0.30