Attaching HMP378 to process with fitting body - HMT370EX

HMT370EX User Guide

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User guide
Figure 1. HMP378 fitting body and clasp nut
Clasp nut (27 mm hex nut)
Fitting body (24 mm hex head): ISO1/2 solid structure or NPT1/2 solid structure
Sealing material (use one of the following options):
  1. LOCTITE® No 542 + activ. No 7649 (T=−55 … +150 °C (-67 … +302 °F))
  2. MEGA-PIPE EXTRA No 7188 (T=−55 … +170 °C (-67 … +338 °F))
  3. PTFE tape (T=−60 … +210 °C (-76 … +410 °F))
To attach the probe to the process:
  1. Detach the fitting screw from the nut and slide it off the probe body.
  2. Attach the fitting screw to the chamber wall with a sealing washer. Tighten the fitting screw into the threaded sleeve with a torque wrench. The tightening torque is 150 ± 10 Nm (110 ± 7 ft-lbs).
  3. Insert the body of the probe into the fitting screw and attach the nut manually to the fitting screw so that the connection feels tight.
  4. Tighten the nut a further 50-60° (approximately 1/6 turn) with a wrench. If you have suitable torque wrench, tighten the nut to max 45 ± 5 Nm (33 ± 4 ft-lbs).
    Draw a line on the clasp nut hex and the fitting body hex to mark the 50-60° (1/6) turn tightening rotation.
    Take care not to overtighten the clasp nut to avoid difficulties when opening it.
CAUTION Take care not to damage the probe body. A damaged body makes the probe less tight and may prevent it from going through the clasp nut.
CAUTION In pressurized processes it is essential to tighten the supporting nuts and screws very carefully to prevent loosening of the probe by the action of pressure.
CAUTION When HMP378 is installed in a process with a pressure differing from normal atmospheric pressure, you must enter the pressure value of the process as an environmental compensation in order to receive accurate measurement results. For information on entering environmental compensations with the transmitter display interface or Vaisala Insight PC software, see Environmental compensation and measurement settings overview.