Eng-Tips is the largest engineering community on the Internet

Intelligent Work Forums for Engineering Professionals

Search results for query: *

  1. MacMcMacmac

    -94 F dew point dry air - issue with condensation

    A chilled mirror dewpoint monitor is a much faster reacting device for dewpoint measurement.
  2. MacMcMacmac

    Exhauster Performance Estimation for Gas Turbine Altitude Testing

    Yes, it's time to make a case and do some work.
  3. MacMcMacmac

    Exhauster Performance Estimation for Gas Turbine Altitude Testing

    Thank you George. Some further snooping turned up the following curves: The line of interest would be the short fellow at lower right. Flow looks promising. Outlet pressure is above ambient, so it looks like it might do the job. No indication of how performance might drop off under altitude...
  4. MacMcMacmac

    Exhauster Performance Estimation for Gas Turbine Altitude Testing

    Hello George, Thanks for replying to my tome! Here is all of the information I have on the 5MW compressor performance: I find it odd that the flow through the second stage only goes up by about 200cfm when coupled to the first, but it is what it is. I am banking on the much better pressure...
  5. MacMcMacmac

    Exhauster Performance Estimation for Gas Turbine Altitude Testing

    Good Day. Here is a rather long-winded explanation of my issue, and a request for assistance if you have a spare few minutes. We have had a failure on our 2MW exhauster set. Last year, we spent quite a lot of time and money getting one of our 1350hp motors on this unit to within acceptable...
  6. MacMcMacmac

    Online Cleaning of Compressor Impellers

    Thank you. It seems like the risks outweigh any benefits. We have all vibration and temperature monitoring in place, but the risk of greater damage is unacceptable. I was just wondering if there was an industry standard method of cleaning online, and it appears not to be the case. Oddly enough...
  7. MacMcMacmac

    Online Cleaning of Compressor Impellers

    Thank you for the reply. The tubesheets will be plain carbon steel with Cupro/Nickel tubes as per the original as-delivered drawings. They are expanded to fit the tubesheet. It was frustrating to find out the OEM for the coolers had disposed of the original engineering drawings. Not...
  8. MacMcMacmac

    Online Cleaning of Compressor Impellers

    Hello. I was wondering if there is an approved method of cleaning centrifugal compressor rotors while in service. Our main 8MW compressor is once again experiencing a build up of material on the 4th stage impeller due to a leak in the 3rd to 4th stage intercooler. The corrosion inhibitor is...
  9. MacMcMacmac

    Magnetic Center of 1MW Wound Rotor Motor

    Well, to close off this thread just out of courtesy to those that replied, let me say, it has all ended well. The motor was installed on Monday. The shaved feet seemed to aid in a very rapid and satisfying alignment, and power up on Tuesday revealed reduced, but still high vibration. Virtually...
  10. MacMcMacmac

    Magnetic Center of 1MW Wound Rotor Motor

    Hello again guys. Sorry to leave you hanging. The multiple mag centers are more of a (me) grasping at straws explanation for a problem that has bedeviled us for almost a year now. I have faith the shop doing the work is capable, since I visited back in late October and had a good tour. There was...
  11. MacMcMacmac

    Magnetic Center of 1MW Wound Rotor Motor

    thread237-507222 In reference to the above thread: The 1MW, 1780rpm wound rotor motor is experiencing excessive axial vibration after overhaul to replace D.E. bearing which failed due to a lack of lubrication. A year on, and this issue has not been solved. The Hail Mary play was to take out...
  12. MacMcMacmac

    Glycol Issue Closed loop

    Ok. Sounds good. We have a very good Nalco rep who is well aware of the city water conditions. I'm sure he won't mind being able to increase the scope of his contract.
  13. MacMcMacmac

    Glycol Issue Closed loop

    So, we've sent off the goop to be analyzed and will be getting the glycol itself analyzed as well. Looking through the manuals of both CargoCaire units, the type of glycol is indicated, but there is no mention of ongoing analysis or changeout intervals. You don't know what you don't know, or...
  14. MacMcMacmac

    Glycol Issue Closed loop

    Hello again. We just shut down for our annual maintenance an I was greeted with the following mess. Glycol was replaced in 2014 with GE Corrshield 4404. Unit is a Munters CargoCaire dehydration unit utilizing a Carrier chiller to remove heat from the system. Just wondering if anyone has...
  15. MacMcMacmac

    General Guidance on Babbitt Bearing Running Temperatures.

    Hello. There are 6 bearings being monitored on this machine. Peak to peak has our Bentley Nevada gauge pegged at over 100 microns at the motor d.e. Temperature probes are in wells machined into the steel bearing carriers. The oil temperature is monitored leaving the oil cooler. The probes...
  16. MacMcMacmac

    General Guidance on Babbitt Bearing Running Temperatures.

    Good Day. We have a large turbo exhauster here that we are trying to solve a vibration issue on. It will peg the vibration monitoring meter at startup, but gradually level out within acceptable limits after running for an hour or so. We are trying out various theories as to why the vibration has...
  17. MacMcMacmac

    Magnetic Center of 1MW motor

    Well, the motor goes off tomorrow. The motor apparently had enough centering travel to cause the hub faces to meet at startup, uncoupled, when it was equipped with the original sleeve bearings, as told to me by my supervisor. This may well have been the source of the thrust bearing loading and...
  18. MacMcMacmac

    Magnetic Center of 1MW motor

    I agree. I see no reason to have as much float in this shaft, even though the motor overhaul shop says it is nothing to worry about. It looks like this motor is going to be sent out again to have the work inspected. I also agree that the babbitt bearing wear is something that has probably...
  19. MacMcMacmac

    Magnetic Center of 1MW motor

    I removed the front cover, pulled the couplings together to get the spacer ring out far enough to pull out by hand to measure the o.d., then I reinstalled it and bottomed out the ring and bearing in its bore with an Enerpac, until I just felt resistance in the lever. This is probably a more...
  20. MacMcMacmac

    Magnetic Center of 1MW motor

    Thank you everyone. First let me clarify a mistake I have made. The shaft end clearances are about 5/16", the total end float of the rotor is about .110". This is still in sharp contrast to the second motor coupler which exhibits zero float in the exact same configuration. I cannot move that...
Back
Top