Maintenance

Schedule

To ensure satisfactory operation of the pumping equipment, frequent inspection and periodic maintenance are required. An inspection and maintenance log should be kept and the inspector is to immediately report any problems. Unusual applications with abnormal heat, moisture, dust, etc., may require more frequent inspection and service.

Recommended Spare Parts

The list of recommended spare parts will depend on factors such as the following:

Normal supplier lead time when ordering parts.

If pumping equipment is for use as normal duty or severe duty, and if there is backup pumping while a unit is down for maintenance and parts replacement. Below is a suggested list of spare parts. For intermittent or non-critical service:

• Stuffing box packing (Item 13
• Ball Bearing Set (Item 16 and 18)
• Bearing Seal Set (Item 47 and 169)
• Bearing Cover Gaskets (Item 73B)
• Set of Shaft Sleeves (Item 14 and 14A)
• Set of Sleeve O-Rings (Item 14B)
• Set of Casing Rings (Item 7)
• Set of Impeller Rings, if supplied (Item 8)
• Gasket, Casing (Item 73A)
• Packing gland and studs or gland bolts. For continuous or critical service (in addition to above)
• Complete Rotating Element preassembled.

Consumables

Items normally used in the maintenance of pumping equipment may include the following, but depending on the type of unit some items may vary:

• Lubricant (grease or oil)
• Cleaning materials
• Touch-up coating 
• Hand tools
• Measuring equipment (feeler gauges, dial indicator, etc.)

Tightening Torques

Proper tightening of fasteners is very important. The torque values depend on the size and grade of the fasteners used. The values in the table below apply to non-lubricated parts.

When assembling a pump, cross-tighten the screws in order to avoid misalignment, binding and leakage. Torque value shown are for clean lubricated threads and gasket joints.

Dismantling

Before starting disassembly of the pump, it is recommended that a set of spare parts be obtained. Peerless Pump does not recommend reuse of gaskets, O-rings, packing rings, or ball bearings.

1. Shut down pump.
2. Clear a large area adjacent to the pump as a storage space for pump parts as they are dismantled.
3. Disengage the coupling halves. Refer to the coupling manufacturers' instructions.
4. Remove the nuts from the gland bolts and remove packing glands from the shaft. The packing gland halves are separable.
5. Remove all fasteners securing the upper casing and from the bearing caps from lower casing. Match mark bearing caps to lower casing .
6. Use the jack screws on the bottom side of the lower casing split flange to separate the upper and lower casings. Turn the jack screws back below the split flange surface to avoid re-assembly interference.
7. Remove the upper casing by use of lifting lugs or customer supplied eye bolt 0.5 - 13" [13-330 mm] UNC threaded into top.
8. Place slings around the shaft near the bearing housings and lift rotating element from lower casing. Tap lightly on the underside of the bearing housings to separate the housings from the brackets as required.
9. Place rotating element in a convenient work surface.
10. Loosen set screws and remove the coupling half.
11. Tap from the back of the hub or use a puller.
12. Remove coupling key, and outboard deflector.
13. Take out cap screws to remove bearing covers and the gaskets. Remove inboard bearing cover seal from cover only if replacement of seal is required.
14. Remove retaining ring from outboard end of shaft.
15. Remove housings, bearings, and bearing housing seals as units with a bearing puller.
16. Remove deflectors.
17. Remove casing rings.
18. Remove packing rings, lantern rings if provided, and stuffing box bushings.
19. Loosen shaft sleeve set screws then loosen shaft sleeves with a spanner wrench.
20. A seal between the shaft and sleeve is made with an O-ring in a groove in the sleeve. Use care not to damage the O-ring.
21. Remove the impeller from shaft with an arbor press.
22. Remove impeller key.
23. Clean all parts.
24. Clean all metal parts (except bearings) with a solvent. Use a bristle brush (NOT metal or wire) to remove tightly adhering deposits.
25. A fiber scraper may be used to remove the gasket and shellac from casing flanges.
26. Recondition or replace worn parts Perform detail inspection as follows:
27. Check O-rings and bearing cover gaskets for cracks, nicks or tears; packing rings for excessive compression, fraying or shredding, embedded particles (dirt or metal). Replace if defective in any way.
28. Mount the shaft between centers or on vee blocks. Check for eccentricity throughout entire length with a dial indicator; eccentricity must not exceed 0.003" [0.08] total indicator reading. Check that threads are clean and sharp. Surfaces on which bearings mount must be smooth, have a finish of 32 µin [0.81 µm] or better, and the shoulders square and free from nicks.
29. Examine passages for cracks, dents, gouges or embedded material.

Wear Ring

Wear rings provide a close-running, renewable clearance to reduce the quantity of liquid leaking from the high-pressure side to the suction side. These rings depend on the liquid in the pump for lubrication. They will eventually wear so that the clearance becomes greater and more liquid passes into the suction. This rate of wear depends on the characteristics of the liquid pumped.

Badly worn wear rings will result in severe degradation of pump head and flow rate, particularly on small pumps. Examination of wear patterns can provide valuable information in diagnosing pump problems and determining their origin.

Worn wear rings or surfaces can be replaced to restore hydraulic performance.

Measure the OD of the impeller wear surface or impeller ring and the ID of the casing ring. Compute the diametrical clearance (ID minus OD) and compare with the limits below. If measured diametrical clearance exceeds two times values, repair or replace to restore design clearance. ID surface of casing ring must be smooth and concentric with ring OD.

If impeller clearance is found to be out of tolerance, replace casing wear ring. It may be necessary to consider machining impeller wear surface for wear ring installation (if not originally supplied) to return to approved clearance. If the impeller must be machined to install new impeller rings, be sure machining is concentric with impeller bore. 

Inspection and Repair

Inspection. Visually inspect parts for damage affecting serviceability or sealing. Emphasize inspection of mating parts having relative motion- wear rings, for example. Perform detail inspection as follows:

1. Check O-rings and bearing cover gaskets for cracks, nicks, or tears; packing rings for excessive compression, fraying or shredding, embedded particles (dirt or metal). Replace if defective in any way.
2. Mount the shaft between centers or on vee blocks. Check for eccentricity throughout entire length with a dial indicator; eccentricity must not exceed 0.003" [0.08 mm] total indicator reading. Check that threads are clean and sharp. Surfaces, on which bearings mount must be smooth, have a finish of 32 µin [0.81 µm] or better, and the shoulders square and free from nicks.
3. Examine impeller passages for cracks, dents, gouges or embedded material.

Assembly

1. Support pump shaft in blocks and rails to protect it from bending or being damaged during the re-assembly process.
2. Check that the shaft is straight and free of nicks and scratches. Remove with a fine file all burrs and scratches.
3. Coat the shaft lightly with oil.
4. Place impeller key in shaft key way.
5. Align impeller on shaft and install with an arbor press or brass tubular sleeve and hammer. When assembled, the impeller vanes must rotate in the proper direction.
6. Impeller hub must be centered on shaft journal.
7. Install shaft sleeve set screws in shaft sleeves. Assemble shaft sleeves to the shaft and hand tighten against the impeller. Do not tighten shaft sleeve set screws.
8. Install the stuffing box bushings.
9. Locate casing rings on impeller.
10. If casing and or impeller wear rings are required, fit wear rings into the casing or onto the impeller skirt. Contact Peerless Pump if rings should be pressed or secured to part as needed. Rings final clearance should provide the necessary clearance. If clearance is not achieved, machine rings prior to proceeding.
11. Place in board deflectors on shaft.
12. If previously removed, install bearing housing seals into housings. 
13. Press housing-bearing-seal assemblies on shaft to seat bearings against shaft shoulders.
14. Install bearing retaining ring in groove against the out board bearing.
15. Install gaskets on bearing covers. Use factory supplied parts or cut replacement gaskets from 0.06" [1.52 mm] No. 444 Vellumoid.
    EXCEPTION: For all models using 3306 size outboard bearing, gasket 73B is 0.03" [0.8 mm].
16. Attach in board and outboard bearing covers. In the assembled position, the greased rain tap must be located at bottom in a horizontal plane.
17. Install outboard deflector, and coupling key; assemble coupling half on the shaft and tighten the setscrews.
18. Affix the new casing gasket to the lower casing with shellac.
19. Use slings around the shaft near bearings to set rotating element into lower casing.
20. Position the casing rings and both bearing housings so that all dowel pins engage in slots in the lower case split surface.
21. Assemble both bearing caps per match marks and tighten the cap screws.
22. Adjust the shaft sleeves to center the impeller in the lower casing volute, and tighten both shaft sleeves with a spanner wrench, then add Locktite to the shaft sleeve set screws. Then tighten shaft sleeve set screws according to section 7.4 Tightening torques.
23. Cover the top side of the casing gasket with a mixture of graphite and oil.
24. Install the gland bolts. Carefully locate the upper casing on the lower, making certain the dowel pins engage.
25. Install cap screws and tighten working from the center of the casing to each end, to the appropriate torque values. 
    • Tightening torques
      •  If any cap screws require replacement, use only parts with equal or greater tensile strength.
26. Rotate shaft by hand to check that it turns freely.
27. Push the stuffing box bushings to the rear of the stuffing boxes.
28. If the stuffing box is not packed from factory, it should be packed prior to startup following the below guide.
29. Clean the stuffing box.
30. Check that the packing rings are of proper cross-section and length.
31. Stagger the joints 90° apart.
32. The rings should butt tightly but not overlap at the joints.
33. Tamp down the individual packing rings, but not too tightly, as this may result in burning the packing and scoring the shaft or shaft sleeve.
34. Where compatible, lightly lubricate the inner and outer packing diameter with a suitable lubricant. When a lantern ring is required, make sure that sufficient packing is placed in below the lantern ring so that the bypass line intersects the packing container bore adjacent to the lantern ring and is not blocked by the packing.
35. The pipe supplying sealing liquid should be fitted tightly so that no air enters. If the liquid to be pumped is dirty or gritty, clean sealing liquid should be piped to the stuffing box in order to prevent damage to the packing and shaft sleeves.
36. Clear sealing liquid is also required if the stuffing box materials are not completely compatible with the pump liquid. The sealing liquid should be at a pressure sufficient to ensure a flow of clean liquid into the pump but not so high as to require excessive tightening of the packing.
37. Insert two packing rings, lantern ring if provided, and three packing rings. Insert each ring separately and stagger the joints of successive rings 90 degrees.
38. Insert the packing glands and set the gland bolt nuts finger tight.
39. Rotate shaft by hand to check that it turns freely.
40. Replace all drain plugs if removed during disassembly.
41. Re-lubricate the bearings.
42. Make sure that the pump shaft spins freely.