The following paper is an excerpt from my book "Bill Mc Nally's Centrifugal Pump And Mechanical Seal Reference Manual". The words marked in blue reference you to the alphabetical section of the book or directly to the subject on the CD for a detailed explanation of that particular topic. If you do not have a copy of the book or CD you can find a lot of the information in the individual papers I have published on the web.Check out the index for a list of my papers by subject.
Some one has to install the centrifugal pump and all its associated hardware. The quality of this pump and driver installation will have a major affect on the performance and reliability of the pump, especially if it is equipped with a mechanical seal.
The pump will be installed on a baseplate. The baseplate will be attached to a foundation and grout will be placed between the baseplate and the foundation to transmit any vibrations from the pump to the foundation.
Once the pump and driver are firmly on the foundation it will be time to connect the piping. Be sure to pipe from the pump to the pipe rack and not the other way, so as to avoid pipe strain that will interfere with the operation of the mechanical seal and bearings. There are many piping recommendations that you should be familiar with. The pump to driver alignment can be made at this point but you should check the alignment after the pump has come up to its operating temperature because metal parts expand and contract with a change in temperature.
If this is a new piping system some people like to install packing in the pump and run on packing until the new piping has been cleaned of slag or any junk that might be left in the piping system. If it is not a new installation, and there is a mechanical seal in the stuffing box, then installing the mechanical seal environmental controls will come next.
If the pump has an open or semi-open impeller it is time to make the initial impeller setting. The final clearance can be set when the pump comes up to its operating temperature. It is important to note that if you do not have a cartridge seal installed in the pump the seal face loading will change as you make both the initial and subsequent impeller settings and there is nothing you can do about it.
You will now want to do a proper venting of the pump. If it is a vertical installation you will have to pay particular attention to keeping air vented from the stuffing box while the pump is running and be sure to vent the space between dual seals if they have been installed.
After you have done all of the above, it is time to check out the mechanical seal environmental controls to be sure they are working properly. In most cases the environmental control will continue to run after the pump has stopped. Be sure the operators understand this or they might be tempted to shut the control off when the pump is between batches. Seal quench is always a problem with operators because the steam or water coming out of the seal gland looks like the seal is leaking.
A constant monitoring of the pump is a good idea. Are you familiar with some of the more popular monitoring methods? Unlike vibration analysis, monitoring can tell you if some part of the pump is getting into trouble before the vibration starts.
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