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Recent content by apatjr

  1. apatjr

    ASME PPC-1 traning

    We were asked to develop a torquing procedure to follow PPC-1. But now our customer asking to submit a traning certificate. We're basically bolting about 40, 2", 3" and 4" flanges. Does ASME PPC-1 require a certificate?
  2. apatjr

    Relief Valve Sizing for Vessels Containing Solids

    The thermal expansion calculations for pressure vessels are based on an empty vessel. If the empty vessel is in a fire and the gas stored starts to expand rapidly the relief valve will protect the vessel from damage. However, what if the vessel is filled with a solid like desiccant in a...
  3. apatjr

    D1.3 & Macrophotograph Requirement

    We are using a GMAW procedure to seal weld a container's sheet metal wall. We had to submit our procedure for review. We've been asked to submit a copy of the macrophotograph of the weld used in qualifying the procedure. Unfortunately, we did not get it done as we were only using the procedure...
  4. apatjr

    Starting Compressors at Low Ambients

    Yes, The altitude is sea level. The humdity will vary from 40% to 100% with 77% being the mean. The pressure band will be to unload at 155 psig and reload at 145 psig. The barometric pressure will vary from 990mbar to 1037 mbar with 1015 mbars being the mean.
  5. apatjr

    Starting Compressors at Low Ambients

    JRLAKE, The concern is from an engineer reviewing our equipment. He has experience with recips and it trying to get me to mathematically prove what the horsepower increase is going to be. I've told him its a waste of time that rotaries and recip do not operate the same, but I'm obliged to try...
  6. apatjr

    Starting Compressors at Low Ambients

    JRLAKE, Thanks for the input. Yes, the rotary is an oil flooded screw. We will be running two 50% units so they should be loaded most of the time. My thoughts on the cold ambient air is that on entering the air-end's compression chamber, the cold air will absorb the heat from the lubricant...
  7. apatjr

    Starting Compressors at Low Ambients

    We're working on a project where some 225kW rotary compressors are operating outside. The ambient temperature will vary from 21 to 93 degrees F throughout the year. When operating the compressors will be operating at approx. 205 degrees F. The units have freeze protection and will not be...
  8. apatjr

    Copper faced earth lug

    Don't know. As in most spec work someone in the past wrote it into a spec and that spec becomes self substaining whether it makes any sense and they want to follow it.
  9. apatjr

    Copper faced earth lug

    We have to weld grounding lugs on our package skids. Usually we weld a small stainless steel pad in the corners for the customer to ground to. We have been asked to supply a copper faced ground. We would rather not go to a plating company as we have such a small quantity of pieces. Does anyone...
  10. apatjr

    ATEX approved small PLC

    Thanks guys, I was so focused on finding a rated PLC that I didn't think of the obvious. Your input is much appreciated.
  11. apatjr

    ATEX approved small PLC

    We're trying to design a small control panel for use in an ATEX Zone 1 area. So far we've found all the end devices that are suitable for this area. We usually use an Allen-Bradley Micrologix 1500 in the US as we only have 5 inputs/7 outputs and 2 anlaog inputs through an expansion module...
  12. apatjr

    Allowable Nozzle Load Location

    We are being asked to supply the allowable nozzle load at a vessel contained inside a package skid. This nozzle connection is supported within 5 feet as the piping changes direction. We've supplied the allowable nozzle loads at skid edge connnections, which is where the customer will hook-up...
  13. apatjr

    Looking for Hazardous Area Hourmeter

    Resqcapt19 I'll have to address this with UL. I noticed that the exception also mentions solenoids and yet all our solenoids are rated for hazardous areas. Thanks for the insight.
  14. apatjr

    Looking for Hazardous Area Hourmeter

    Old Dave, Thanks for the input. However, we're trying to eliminate the use on any NEMA 7 enclosures. We get our control panels inspected by UL and as such we have to supply documentation proving the components are suitable for the area. I've been told that if our hourmeter is fed power...
  15. apatjr

    Looking for Hazardous Area Hourmeter

    We presently seal a standard hourmeter inside a NEMA 7 instumenatation enclosure. However, this means either using a pour fitting or a cable terminator. In most cases this forces the hourmeter outside our control panel. We are trying to eliminate this extra step. An instrinsically safe device...

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