Meriam 70H_72H High Pressure Wet Tap Accutubes with Integral 3-Valve Head and Optional RTD - Manual (Page 15)

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4.5.26 Verify the alignment of the probe head with respect to the pipe line. The side
pressure port should point directly upstream. Refer to Figure 4.1
4.5.27 The Accutube is now ready to be placed into operation.
4.6 PROBE REMOVAL
4.6.1
Close the high and Low-pressure instrument valves.
4.6.2
Disconnect or modify line connections to head to allow probe removal.
4.6.3
As a precaution, hold the probe in place and adjust the safety chain to allow 2
links of slack.
4.6.4 Still holding the probe loosen the packing gland fitting nut slowly until the
probe can be withdrawn.
4.6.5
Withdraw the probe until the chain tightens. Retighten the packing nut.
4.6.6
Gently attempt to close the insertion valve. If the probe prevents if from
closing, adjust the chain to allow 2 additional links of slack. Remove the probe
further and again attempt to close the valve. Repeat this as necessary.
4.6.7
With the valve closed, there is still residual pressure in the upper portion of the
assembly. This can be relieved by venting either or both of the valves on the
Accutube head.
4.6.8
The probe can now be fully removed.
4.7 HIGH PRESSURE WET-TAP: SERIES 37L, 70H & 72H
4.7.1
EQUIPMENT REQUIRED:
4.7.1.1 Accutube probe with all wet tap mounting hardware.
4.7.1.2 Instrument valves (1/2” NPT) to be assembled onto the probe.
4.7.1.3 Pressurized drilling equipment - suggested source is Mueller Co.
(Decatur, Ill.) Model D-5 or DH-5 with necessary drill holder and
adapter nipple to attach to 3/4” FNPT for the 1/2” diameter probe, 1-
1/4” FNPT for the 1” diameter probe, and 3” - 150 lb. flanges for the 2-
3/8” diameter probe. See Table 4 for drill size required.
4.7.1.4 Welding Equipment.
4.7.1.5 Standard pipe wrenches and hex wrenches.
4.7.2 INSTALLATION PROCEDURE - 1/2” AND 1” DIAMETER PROBES WITH
SOCKET DRIVE
4.7.1.1 Verify that the operating pressure and temperature are within the
Accutube probe, and valve limitations. Refer to Table 5.
4.7.1.2 In determining probe installation, a vertical probe position, either
above or below the pipe is recommended for 12” line size and greater
due to the assembly weight extending to the side. Support of the