Routine maintenance

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I just finished a very routine repair job, and I just thought... so I’m posting it on the forum. Last night, around 10 o’clock during the night shift, I received a call from an operator who said that a pump in the unit had just had its seal replaced, and the motor was vibrating heavily while it was in operation. Upon arriving at the site, I used a vibration meter to measure the horizontal vibration; it was as high as 19.5 mm/s at the motor drive end, 6.8 mm/s at the pump drive end, and 3.6 mm/s at the non-drive end ； The motor vibrates extremely violently; touching it with your hand makes it feel like it’s about to jump. It was already after 11 p.m., and I told the shift supervisor that we might as well switch over and handle it tomorrow, as it was cold and raining at the time. But the shift supervisor said no: L ； Since the vibration became severe right after the pump’s seal was replaced, I didn’t dare to assume outright that it was a problem with the motor. Additionally, the seal that was just installed started leaking due to excessive vibration, which also angered the operator. Power was cut off while invoicing was being issued; the double-diaphragm coupling was removed to check its alignment. The lateral deviation from the circular path was 0.50 mm, and there was a 1-mm difference in height between the motor and the pump. How is it possible that such alignment issues are not addressed before the components are reinstalled and tested? That’s why I’m afraid of those weird colleagues who take advantage of others… When dealing with such irresponsible coworkers, I have to step in and clean up their messes every time. I really hate doing the alignment task; it’s better when there’s a laser alignment device. Otherwise, I have to rely on readings from a dial indicator and adjust the shims accordingly, which takes so long that it’s not until after 1 a.m. that I finally finish it. During operation, the horizontal vibration at the motor drive end was still 11.6 mm/s, while it was 3.2 mm/s at the pump drive end. At that point, the shift supervisor started complaining, saying that things still weren’t working properly... I said it was a problem with the motor and asked an electrician to test the motor separately (I was quite firm in my attitude; actually, I wasn’t entirely confident, as the alignment values were slightly higher than the specified limits. But I remembered that double-diaphragm couplings have compensating mechanisms, so even if there’s a slight deviation in alignment, the vibration shouldn’t be that severe. I decided to take a chance). The shift supervisor insisted firmly that it couldn’t possibly be a problem with the motor, asking how it was possible that there wasn’t much noise if there really was a problem with the motor Heh, I sneered (as if it were some kind of professional technique…) I removed the intermediate section of the coupling and tested the motor alone; the vibration levels in both the front and back were above 6.5 mm/s. Now I was relieved, while the team leader was at a loss for words. I then said I’d be leaving…