Maintenance of horizontal multi-stage pumps
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Our company has some horizontal multi-stage pumps, which are equipped with double mechanical seals on both sides and are lubricated with 15# white oil. There are frequent problems with white oil leakage (the new pump has not been used much). This issue occurred again after the manufacturer’s staff carried out repairs (at the tail end); upon inspection, it was found that the bearings had changed color due to high temperatures. Could this be caused by an overly small bearing clearance? How to adjust the bearing clearance and rotor end play of a multi-stage pump? Which marine friend has the maintenance documents for horizontal multi-stage pumps?
Adjust by adding or removing shims at the tail bearing end cover
Our equipment also has similar pumps, but we use oil grade 46. We have encountered the same issue you mentioned – problems with the oil seals. What is the medium you use for transportation? Has water gotten into the oil?
Our equipment also has similar pumps, but we use oil grade 46. We have encountered the same issue you mentioned – problems with the oil seals. What is the medium you use for transportation? Has water gotten into the oil?
The bearing changes color at high temperatures, which is caused by an excessively small bearing clearance. It can be adjusted by adding or removing shims at the end bearing cover.
The bearing changes color at high temperatures, which is caused by an excessively small bearing clearance. It can be adjusted by adding or removing shims at the end bearing cover.
White oil is generally used for flushing and cooling mechanical seals; it is not intended for lubricating bearings. Please confirm: (1) Is white oil meant to be used as a flushing fluid for mechanical seals? (2) What is the flushing scheme for the mechanical seal? (3) Is the lubricating oil for the bearings appropriate?
There are many reasons why bearings turn blue at high temperatures. For example, there may be installation issues when fitting the positioning bearings of multi-stage pumps; when 7-series positioning bearings are installed in pairs, a certain amount of play is required, and without this play, the bearings may change color and turn blue. 2. A lack of oil in the bearing can also cause it to heat up and turn blue. 3. Excessive axial force causes discoloration to a blue color. The series connection of the rotors can be adjusted by modifying the shims in front of and behind the balance discs, while the bearing clearance can be adjusted by changing the bearing caps. If the bearing clearance is too small, a shim of 0.03 mm can be added to the inner ring of the bearing
Your wording is a bit misleading. By ‘white oil lubricant,’ you mean the lubricant used for machine seals, right? (It should be called a machine seal coolant; it does have a lubricating function as well.) Oil is what’s used in bearing housings, right? I’ve never heard of using white oil in that context Two issues: 1. The non-driving end seal keeps leaking, 2. The bearings are overheating ； The chemical industry uses inspection mechanisms for machines and pumps – don’t you have any such mechanisms? What was the temperature of the bearing housing before? How much vibration is there per day? After the mechanical seal is removed, is the leakage caused by damage to the rotating and stationary rings, or is it due to corrosion of the O-ring? What is the compression amount of the new seal? How many serial connections? For example, if the shaft diameter is 6 mm and the compression amount of the mechanical seal is 5.5 mm, then the mechanical seal will eventually break – it’s only a matter of time. Which bearing gap are you referring to, the one that is too small? Is the hat worn too tightly? The back is too tight, making it very difficult to turn the crank by hand; you’ll know it as soon as you try, so this possibility is low. What is the fit clearance between the inner ring of the bearing and the shaft? (Heating is required for normal installation); measure it using an inner diameter gauge and a micrometer ； What is the fit clearance between the outer ring of the bearing and the bearing housing? If these gaps are too large, it will cause the bearing temperature to rise. Additionally, during inspection, what is the amount of play at the location where the bearing is installed, as measured with a dial indicator?
The random data for your pump includes the relevant clearance requirements and maintenance requirements; check them and have the maintenance team carry out the work in accordance with those requirements.
The medium is liquefied gas, and the lubricant is used to lubricate between the two sets of mechanical seals. Generally, it is the medium entering the lubricating oil circuit that causes the pressure in the lubricating oil tank to rise