7.7.5. Check of wheel cylinders of back brakes at the stand


Fig. 7-18. Scheme of check of wheel cylinders of back brakes: 1 — an emphasis of pistons; 2 — the tested cylinder; 3 — a cylinder arm; 4 — the manometer of low pressure; 5 — the manometer of high pressure; 6 — the cylinder for creation of pressure; 7 — a vessel; 8 — a flywheel

Install the cylinder on the stand, attach to it the pipeline from manometers (fig. 7-18) and pump over system.
Adjust an emphasis 1 so that pistons of the wheel cylinder rested against them.
Check lack of leak of liquid. Connect the manometer of low pressure; slowly rotating a flywheel of control of the drive cylinder, establish pressure of liquid of 0,05 MPas (0,5 kgfs/cm2).
Make sure that the established pressure keeps within 5 min. Repeat similarly test with a pressure of 0,1-0,2 – 0,3–0,4–0,5 MPas (1–2–3–4–5 kgfs/cm2).
Reduce pressure and connect the manometer of high pressure. Following the specified rules, repeat tests with a pressure of 5-10-15 MPas (50–100–150 kgfs/cm2).
Pressure decrease because of leak of liquid through sealing elements, connections of pipelines, unions for pumping of liquid or through a casting time is not allowed.
Reduction of pressure is allowed insignificant (no more than 0,5 MPas (5 kgfs/cm2) within 5 min.), especially with more high pressures, because of shrinkage of sealants.