- Exercise 18 Questions 1 What Is The Function Of A Bleed Off Circuit 2 Is A Bleed Off Circuit Energy Efficient Why 1 (35.28 KiB) Viewed 102 times
- Exercise 18 Questions 1 What Is The Function Of A Bleed Off Circuit 2 Is A Bleed Off Circuit Energy Efficient Why 2 (29.73 KiB) Viewed 102 times
- Exercise 18 Questions 1 What Is The Function Of A Bleed Off Circuit 2 Is A Bleed Off Circuit Energy Efficient Why 3 (55.23 KiB) Viewed 102 times
Exercise #18 Schematic 22 less flow to take mere to to cly AL B 12 HIXL P T 21 2 gpm (7.5 pm) * 16 500 psi (34.5 bar &- E! 1 1 5 5 M
11. Trainer Exercise #18: Bleed-Off Flow Control, Bidirectional Description: This exercise requires that a flow control valve bleed off the same portion of the pump's flow regardless of pressure variations in the system. In this type of circuit, the flow control valve does not cause an additional resistance for the pump, but operates by metering a portion of pump flow to tank at existing system pressure which could be less than the relief valve setting. A bleed-off circuit can be used in any application where precision flow is not required and where a load offers an es- sentially constant resistance, le grinding tables, vertically lifting a loed, etc. (Reference Chapter 9 in Bul. 0232-81, Industrial Hydraulic Technology, 2nd Edition) Loose Components: Hoses III. Procedure: a. REFERTO SAFETY CHECK LIST, PAGE 2 b. Reference schematic on the following page. Connect a hose from one of the pressure ports on the connection header (27) to the pressure port "P" of directional control valve (12) c. From another pressure port on the connection header (27) connect a hose to the iniet port of the pressure compensated flow control valve (21). Connect a hose from the outlet port of the pres- sure compensated flow control to the inlet port of the flow meter (16). Connect a hose from the flow meter outlet port to one of the return ports on the connection header d. Connect a hose from tank port T of the directional control valve to one of the return ports on the connection header e. At port "A" of the directional control valve, connect a hose to the rod end port of the cylinder (22) From port "B" of the directional control valve connect a hose to the base and port of cylinder (22) f. Once the circuit has been checked and upon instruction, back out relief valve (5) completely and have handle for vent valve (4) -in the open or horizontal position g. Start electric motor on power unit and slowly close vent valve (4) h. Deadhead the system and then set pressure to 500 ps (34.5 bar) [if pressure doesn't go up to 500 psi (34.5 bar), back out the relief valve to minimum pressure, then notify the instructor) WARNINGI DO NOT ATTEMPT TO OPERATE THE CIRCUIT IF YOU HAVE NOT BEEN ABLE TO REACH 500 PSI (34,5 BAR). THIS IS A SYMPTOM OF A POTENTIALLY DANGEROUS CONDITION As the cylinder retracts, adjust the flow control valve Back out the relief valve to minimum pressure, then stop the electric motor. The students should complete the following questions before dismantling the experimental circuit. Disassemble circuit and put components in their proper storage place. k. L