Meriam 70H_72H High Pressure Wet Tap Accutubes with Integral 3-Valve Head and Optional RTD - Manual (Page 16)

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assembly weight is required for horizontal probe position on larger line
sizes.
4.7.1.3 Prepare the pipe surface for welding. Tack weld the Thred-O-Let in
place and verify alignment. Refer to General Installation, Sections
4.1.3 through 4.1.6.
4.7.1.4 Assemble the close nipple onto the Thred-O-Let. The close nipple is a
special design nipple that serves as a drill guide and a support for the
Accutube probe.
4.7.1.5 Assemble the insertion valve onto the close nipple. Final position of
the valve should be such that the stem of the valve is parallel to the
centerline of the pipe. This assures clearance of the valve handle with
the insertion/retraction rods.
4.7.1.6 Attach the drilling equipment to the insertion valve. Drill the hole
through the wall. Operate the pressure drilling equipment in
accordance with manufacturer’s instructions.
4.7.1.7 After the drill has penetrated pipe, withdraw the spindle on the drill and
close the insertion valve. The assembly is pressurized. Vent pressure by
opening the vent valve or by loosening the drilling attachment.
4.7.1.8 Remove the drill from the insertion valve and in its place assemble the
cage pipe.
4.7.1.9 Assemble the packing gland housing onto the other end of the threaded
cage pipe. Final position of this housing after it is securely threaded in
place should be such that the holes on the insertion flange straddle the
pipe centerline. This position determines the proper orientation of the
Accutube.
4.7.1.10 Assemble the packing rings (Grafoil) into the bore of the packing
housing. The ring must be handled with care. A broken ring is not
reusable. Substitution of alternate type packings will affect
pressure/temperature ratings of the assembly.
4.7.1.11 Assemble the cylindrical shape follower atop the packing rings and
into the packing housing.
4.7.1.12 The retainer is now placed atop the follower and secured loosely in
place with the packing gland socket head cap screws. Do not tighten
the screws at this point.
4.7.1.13 Assemble the instrument valves onto the Accutube probe head.
4.7.1.14 Assemble the insertion/retraction rods and nuts onto probe. The rods
slip through the hole on the insertion bar and extend 2” out the top. A
single nut is assembled to each side of the insertion bar and tightened
so that the rod is secured in place. Loosely assemble the upper drive
nut on the insertion rod up to the lower lock nut. This is done for both
rods.
4.7.1.15 Insert the probe tip into the packing gland assembly and slide it until
the probe tip contacts the inside of the valve. As this is done, the
insertion/retraction rods must be guided through the proper holes on