Eaton Electrical PVE21 manuale d’uso

M-2854-S Released 8/1/90 Overhaul Manual PVE V ariable Pump 12–21 USgpm capacity at 1800 rpm Vickers ® Piston Pumps[...]

2 T able of Contents Section Page I. Introduction 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . A. Purpose of Manual 3 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .[...]

3 Section I – Introduction A. Purpose Of Manual This manual describes operational characteristics and overhaul information for the PVE12, 19(*) and the PVE21(*) – ** variable displacement piston pumps. The information contained herein pertains to the latest design series as listed in T able 1. B. General Information 1. Related Publications - Se[...]

4 C-10 – CG-10 – CV -10 – CVP-12 – CVPC-12 – Pressure compensated (PVE19, 250-3000 psi) (PVE21, 250-2700 psi) Remote control pressure compensator adjustable from 350-3000 psi using and external relief valve. Load sensing PVE19/21 Load sensing (160 psid) with pressure compensation PVE 19/21 Load sensing (350 psid) with pressure compensatio[...]

5 Figure 1. Sectional Views of the PVE Pumps Drive Shaft PVE19 Section View PVE12 Section View Housing Rotating Group T apered Roller Bearing Y oke W afer Plate Compensator Y oke Housing Compensator V alve Block Shaft Seal Shaft Bearing Piston[...]

6 Section II – Description A. General Assembly of a typical pump package is shown in Figure 1. Six types of compensator subassemblies are used with the PVE series pumps. Refer to Section III for principles of operation. See Model Code for pressure settings. 1. Compensator (C), (Flat Cut-Off T ype): A pump using this compensator will maintain a co[...]

7 Section III – Principles of Operation A. Piston Pump Rotation of the pump drive shaft causes the cylinder block, shoe plate and pistons to rotate. See Figure 2. The piston shoes are held against the yoke face by the shoe plate. The angle of the yoke face imparts a reciprocating motion to each piston within the cylinder block. Inlet and outlet p[...]

8 Figure 3. Flat Cut-Off Compensator Compensator Spring Drain Pump Load Cross Hole (Open to Spring Area) Compensator Spool Y oke Stroking Piston Rotating Group Y oke Spring Inlet Outlet D. Compensator (Load Sensing T ype - “ CV ” ) Application A frequent application of pressure compensator pumps is to supply sevo valves or mechanically operated[...]

9 Figure 4. Load Sensing Compensator (CV). Compensator Spring Drain Compensator Spool Y oke Stroking Piston Rotating Group Y oke Spring Inlet Outlet Actuator Load External V alve Spool Orifice ( n P-Pressure Drop) Relief V alve Circuit Operation At Minimum Pressure Refer to Figure 4 during the following description. Assume a no load condition. The [...]

10 External V alve Spool Orifice Size Increased If the external valve spool orifice size is increased, pump outlet pressure will decrease, lowering force against the compensator spool. (See Figure 4.) The compensator spring causes the spool to move, opening the yoke stroking piston to case drain. As fluid is metered from the yoke stroking piston, t[...]

11 Figure 5. Load Sensing Pressure Limiting Compensator (CVP , CVPC, CVPD) Compensator Spring Drain Compensator Spool Y oke Stroking Piston Rotating Group Y oke Spring Inlet Outlet Actuator Load External V alve Spool Orifice Load Sensing Spool Set Screw[...]

12 Section IV – Installation and Operating Instructions A. Installation Drawings The installation drawing listed in T able 2 will show installation dimensions and port locations. B. Mounting and Drive Connections CAUTION Pump shafts are designed to be installed in couplings with a slip fit. Pounding can injure the bearings. Shaft tolerances are s[...]

13 Sound Level Noise is only indirectly affected by the fluid selection, but the condition of the fluid is of paramount importance in obtaining optimum reduction of system sound levels. Some of the major factors affecting the fluid conditions that cause the loudest noises in a hydraulic system are: 1. V ery high viscosities at start-up temperatures[...]

14 Section V – Service and Maintenance A. Service T ools The following standard tools for overhauling the piston pump are shown in Figure 8. Standard T ools and Equipment: 1. T orque wrench with short extension and sockets 2. 1 ” micrometer 3. 1 ” depth micrometer 4. External T ruarc pliers 5. Internal T ruarc pliers In addition to the above [...]

15 Figure 8. Standard T ools. 1 2 3 4 5 6 Figure 9. Special Shaft Bearing Removal and Installation T ools. 1.232 1.500 “ A ” Use for “ A ” Intermediate shaft bearing installation Drive shaft bearing installation Drive shaft bearing removal 4 ” 6 ” 9 ” 1 1/2 ” heavy wall tubing .005 .005 Description A B C V alve Block 1.675 1.300 1.2[...]

16 Figure 1 1. Special Bearing Race Installation T ools. “ C ”“ B ” “ A ” .375 Nominal Pipe Size ABC 1 1/2 ” 4 ” 1.625 1.900 2 ” 4 ” 2.125 2.375 Schedule 80 (extra heavy) .005 Figure 12. Shaft Seal Driver . Aluminum ring Heavy wall tubing Press ring on end of tubing. 0.125 2.500 1.439 1.440 0.250 6.50 1.500 .375 .005 F . Replace[...]

17 G. T roubleshooting T able 3 lists the common difficulties experienced with piston pumps and hydraulic systems. It also indicates probable causes and remedies for each of the troubles listed. TROUBLE PROBABLE CAUSE REMEDY Excessive pump noise. Low oil level in the reservoir Air in the system V acuum condition Oil too thick Cold weather Fill rese[...]

18 Section VI – Overhaul A. General CAUTION Before breaking a circuit connection, make certain that power is off and system pressure has been released. Lower all vertical cylinders, discharge accumulators, and block any load whose movement could generate pressure. After removing the pump from the system and before disassembly , cap or plug all po[...]

19 55 54 53 52 51 50 49 27 30 60 59 58 57 34 35 36 45 55 54 53 52 51 50 49 27 33 72 23 71 70 44 42 40 34 37 35 31 29 26 25 43 41 39 38 36 28 32 64 65 66 69 74 68 67 Figure 13. PVE19/21 Exploded View Refer to Service Drawings for assembly instructions and torque values. Item Description Qty 70 O-ring 1 71 Retaining Ring 1 25 Screw 5 67 Plug 1 68 O-r[...]

20 Figure & Index No. Units per Assembly Description 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 4 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 2 6 1 1 1 1 1 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 Screw Gasket O-Ring Lockwire and Seal Adjusting Plug Back-Up Ring O-Ring Spri[...]

21 4 5 6 7 8 9 10 1 24 3 2 72 56 57 58 59 60 61 62 30 25 55 54 53 52 51 50 49 46 47 48 44 45 27 55 54 53 52 51 50 49 Figure 13. PVE19/21 Exploded View[...]

22 63 9 10 8 7 5 12 1 18 17 16 15 14 13 4 11 19 23 24 3 2 21 20 22 69 68 67 71 70 73 26 29 31 66 43 42 41 40 39 34 38 37 36 35 33 28 32 65 64[...]

23 3. Inspect spring (8) and (16) for wear and parallelism. Spring ends must be parallel. Replace if spring is warped or wear is evident. 4. Inspect seat (9) for wear in the area of spool contact. 5. Inspect spool (10) for excessive wear , galling, scratches, etc. If scratches exist across the spool land, replace the spool and inspect the body bore[...]

24 Figure 14. Cylinder bloc k subassembly disassembly tool. (T ighten nut, remove snap ring, loosen nut to relieve spring tens ion). Figure 14a. Cylinder Block Subassembly parts. F . Inspection Repair and Replacement 1. Check bearing (32) for scoring or brinelling of the rollers (PVE 19/21). 2. Check bearing spacer (33) for burrs (PVE 19/21). 3. In[...]

25 NOTE If shims (51) were destroyed during disassembly , a yoke bearing preload adjustment must be made at assembly . c. Slide the yoke from side to side to loosen the yoke bearing races (54) within the housing. The races are a normal slip fit but may be tight. Use an open end wrench between the yoke and the pintle bearing to help slide out the ra[...]

26 Figure 16. Removal of Front Bearing Race. Figure 17. Front Bearing Removal. Shaft Seal 1 1/2 ” heavy wall tubing 6 ” long. See Figure 1 1. Arbor Press Here Retaining Ring Figure 18. Front Bearing Installation. Shoulder 1 1/2 ” heavy wall tubing 6 ” long. See Figure 1 1. Arbor Press Here G. Assembly of Housing Parts NOTE If a new shaft be[...]

27 a. Assemble pintle bearings (55) on each end of the yoke and insert bearing races (54). b. Install bearing spacer (53) at one pintle end. c. Install O-Ring (52) against spacer (53) into the groove, then install a 0.010 inch shim (51) under pintle cover (50). Install four pintle cover screws (49) and torque to 175 – 185 lbf. in. NOTE Early desi[...]

28 H. Disassembly of V alve Block 1. Do not disassemble check valve parts (64) through (66), unless action of the valve indicates a problem. Check the valve action with a pencil or a screwdriver . Press the check valve in against the spring, it should return and hold firm against the seat. If the check valve is defective, remove and replace the com[...]

29 2. Install pipe plug (69) into valve block (26) and secure. 3. Assemble a new O — Ring (68) on hex plug (67) and thread plug into place. K. Shaft Bearing Preload Adjustment (PVE 19/21 only) NOTE If the shaft bearings, shaft, valve block or housing were not replaced, use the bearing spacer removed during the disassembly procedure to preload the[...]

30 Section VII – T est Procedure A. T est Conditions FLUID MEDIUM: SAE 10W meeting API service classification MS or equivalent. FLUID TEMPERA TURE: 120 ° F ± 5 ° F at pump outlet. Fluid entering the pump must be maintained below a maximum contamination limit of class four according to NAS1638. B. Preliminary Check 1. Rotate the drive shaft thr[...]

31 F . Performance T est of PVE 12/19/21 Piston Pump with “ CG ” Compensator Control 1. Operate pump at 1200 RPM. Set remote control valve to minimum pressure setting. 2. Refer to Figure 23 and adjust load valve (1) and globe valve (1) to 100 PSI system pressure at P1. Observe maximum pump flow and maximum case leakage requirement noted in T ab[...]

32 G. Performance T est of PVE 12/19/21 Piston Pump with “ CV ” , “ CVP ” , “ CVPC ” and “ CVPD ” Compensator Control NOTE Refer to Figure 24 for location of circuit components. 1. Open load valve one (1) and turn compensator adjust - ment plug clockw ise until seated. 2. Operate at 1200 RPM and 100 Psig outlet pressure until all ai[...]

33 Model Compensator Pressure Setting Psig T able 9. Load sensing compensator adjustment range. Lockwire Standby Pressure P2 P @ USgpm (P2-P1) P @ Compensator Cracking Pressure (P2-P1) PVE19*-*-**-CV -10 PVE19*-*-**-CVP-12 PVE19*-*-**-CVPC-12 PVE12*-*-**-C**VPD41 PVE21*-*-**-CV -10 PVE21*-*-**-CVP-12 PVE21*-*-**-CVPC-12 Not Applicable Not Applicabl[...]