|Routine Preventative Maintenance:
Operation and maintenance requirements vary with the type of pump, the type of installation and the type of fluid being pumped. Operating and maintenance recommendations specified by the manufacturer should take precedence and should be implemented upon installation.
|A comprehensive and progressive record should be kept for each pump detailing components and procedures checked, preventative maintenance (PM) performed, maintenance intervals, operations and operational issues. A maintenance routine should be planned with the service conditions in mind rather than as an arbitrary routine or only when the pump malfunctions. A reduction of flow or performance can be determined fairly early by continuous monitoring of the pump and its records.
Preventative routine maintenance extends the life of your pump and associated equipment. PM prevents unscheduled pump downtime while often times indicating more serious problems that will occur without the scheduled PM. Even though PM appears to add costs to pump operation in the short term, PM actually saves money through planned repairs and part replacements rather than extensive, costly and unexpected shut downs.
Maintenance of the pump consists of periodically replacing the wearing parts such as sleeves, neck rings, packing material, lubricating mediums and others. Impellers and diffusers usually have a long life provided the pumped liquid is not corrosive or harmful. Damage may be caused by a combination of factors - corrosion, erosion, electrolytic action, graphitization and corrosion fatigue of the shaft.
A. ROUTINE INSPECTION
Make a systematic inspection of the pump at regular intervals. The frequency required depends upon the operating conditions of the pump and its environment. A pump operating continuously outdoors and/or pumping dirty fluids requires more frequent inspection than one pumping filtered fluids for a short period once per week in a laboratory.
Keep the driver and discharge head free from dirt, oil and grease. Electric motors and starters should be kept as dry as possible. If exposed to dusty environments, motor ventilation passages should be cleaned periodically to prevent overheating.
A list of recommended lubricants, by brand name and manufacturer is provided. CAUTION: Do not use a lubricant which could contaminate the fluid to be pumped or which is soluble in the fluid.
| 1. Lineshaft Bearings:
| a. Oil-drip lubrication: Check the oil level in the reservoir. It should never be less than one-quarter full. Refill with a turbine oil equal in quality to those listed by the manufacturer. Check the drip rate according to manufacturer requirements. Unusually long pumps having more than six shaft bearings require additional drops for each bearing.
b. Pressure lubrication: If a high-pressure system is used, the pressure should be 5 to 10 psi higher than the pump discharge pressure. If the system is the low-pressure type, check for adequate flow of lubricant to the pump.
c. Grease Lubrication: Replenish the grease supply through the grease-gun fitting in the side of the tube nut. Add one shot of grease after every 100 hours of operation.
| 2. Tail bearing in suction manifold:
If the pump is equipped with a lubrication line to conduct grease, oil, or other fluid to the tail bearing in the suction manifold, replenish the supply through the lubrication fitting. This is usually in the base of the discharge head but may be in some other location at the option of the owner. When grease is used, add one "shot" after every 100 hours of operation. For oil-drip lubrication, check the level in the sight gauge and replenish when necessary. If the lubricant is fluid from the pump, check periodically for leaks and stoppages.
In open lineshaft pumps, the packing at the top shaft is supplied with grease through a pressure fitting on the side of the packing container. Add one "shot" after approximately every 100 hours of operation, or once per week to ten days.
Instructions for lubricating the driver are furnished by the manufacturer. Adherence to these instructions will benefit the user by long, trouble-free service.
D. PACKING ADJUSTMENTS
If the pump is equipped with an adjustable packing at the top shaft, adjust the packing gland whenever the leakage rate exceeds two drops per second. CAUTION: Too tight an adjustment of the packing gland can cause premature failure of the packing and serious damage to the shaft.
| 1. Tighten the gland in small increments. One-sixth to one-quarter turn of the gland nuts for each adjustment is recommended. Before making another adjustment, allow the packing to equalize against the increased pressure and the leakage to gradually decrease to a steady rate. Theh recommended leakage rate is approximately one drop per second.
2. When the packing has been compressed to the point that the gland is about to contact the upper face of the packing container, remove the gland, add one extra packing ring, and re-adjust. If this fails to reduce the leakage to one drop per second, remove all of the packing rings and repack with new rings.
3. If the replacement packing is in the form of a continuous coil or rope, it must be cut into rings before installing. This can be done by tightly wrapping one end of the packing material around the top shaft like one coil of a coil spring, and marking the coil with a sharp knife. Rings must hav a gap of 1/16 to 1/8 inch, and the ends must be parallel. After cutting on the mark, this length of packing may be used as a template for cutting all the other rings.
E. REPLACEMENT OF MECHANICAL SEAL
These seals are not made by the pump manufacturer. For information on mechanical seals, consult the seal manufacturer's instruction booklet, which is furnished with the pump.