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Pipe Thread (NPT) Assembly Procedure

1. Apply PTFE tape or paste sealant to MNPT threads starting one thread back from end of fitting.
    When using tape tightly wrap in direction of threads to conform tape to shape of threads.
  a Use 3 1/2 to 4 wraps of tape when assembling PFA threads to PFA material.
  b Use 4-5 wraps of tape when assembling PFA threads to another material other than PFA.
    When using paste pipe sealant fill approximately two threads of the male part.
2. Thread the fitting onto the mating component until hand-tight.
3. Using a wrench, tighten fitting about 4 turns past hand-tight.

PTFE tape = 1/2" wide for all NPT fittings
Note: PTFE tape is not recommended for use in a gaseous application
in•lbs × .11298 = newton•m
In actual laboratory testing, several paste sealants have shown better results than PTFE tape in sealing threaded pipe connections at fluid temperatures up to 250°F (120°C). For applications where fluid temperatures may go above 250°F (120°C) PTFE tape is recommended.

Torque
  In•lbs Newtons•m
1/16" 5.0 0.57
1/8" 7.0 0.79
1/4" 16 1.81
3/8" 23 2.60
1/2" 30 3.39
3/4" 54 6.10
1" 78 8.81
Paste Sealant
2 to 2 - 1/4 Turns 1- 1/4 to 1- 1/2 Turns
1/16" 1/4" 1/2"
1/8" 3/8" 3/4"
    1"

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