How to distinguish between mechanical seals and packing seals
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This post was last edited by foam_ZPTK on 2018-1-17 21:10. How to distinguish between mechanical seals and packing seals? Is there a way to tell what type of sealing structure a pump has just by looking at it?
Under normal conditions, the leakage from a packing seal is significant; you will see water dripping continuously at the shaft seal area. The leakage rate of mechanical seals is very low, usually less than one drop per minute.
Mechanical seals are usually circular. The filler gland is diamond-shaped.
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Fillers and mechanical seals are easy to identify – just look at the gland: a filler uses a gland with only one or two screws, while a mechanical seal has a gland with four screws; in cases involving high temperatures, there is also an auxiliary system
Check the gap between the gland and the pump cover; in the case of mechanical seals, sealing is achieved through surface contact, while there is no sealing mechanism for packing. With packing, the gap is relatively large, and usually only two bolts are used, as it is necessary to adjust the tightening force frequently. For mechanical seals, there is no gap between the gland and the pump cover, so they need to be installed in place directly. In most cases, four bolts are used (although sometimes just two are sufficient)
Mechanical seals that use throttle sleeves also experience leakage:
Packing seal: Easy to install and remove, can be replaced while the pump is in operation; leakage is permitted as long as it is not in a continuous stream, in which case no replacement is needed. Mechanical seal: Replacing the mechanical seal requires disassembling the entire pump; the allowable leakage rate is 5–10 drops per minute. (According to the new environmental regulations, oil should not fall to the ground and gas should not escape into the air.) Therefore, any leakage of the medium is not allowed···