Groth 1720A - Manual (Page 5)

5
The following guidelines should be
observed at installation:
1. Inspect the gasket seating surface of the
tank nozzle flange. It must be clean, free
of scratches, corrosion, tool marks, and
flat.
2. Aluminum valves are furnished with flat
face flanges; they should only be installed
on a mating flat face flange with a full
faced gasket.
3. Inspect the gasket; make sure that the
material is suitable for the application.
4. Lubricate all studs and nuts with an
appropriate thread lubricant. If the valve
will see high temperature service or
stainless steel fasteners are used, apply
an anti-seize compound such as moly-
disulfide.
5. Center the gasket within the bolt circle.
6. Set the valve carefully on the nozzle.
Install the studs and tighten nuts hand
tight. For studs selection for blind tapped
holes see Table 1.
7. Torque all fasteners to half the value listed
in Table 1 in a staggered, alternating
pattern.
8. Make sure that the flanges are not
distorted and that the gasket is evenly
compressed. Make up the final torque
and check that no further nut rotation
occurs at the torque value specified on
Table 1 below:
TABLE 1 - Bolt Torque & Stud Specifications - ANSI #150 Flange Connections
Mounting Stud Torque - Lb.In.(kg.m) Number of Special Stud Specifications*
Flange Raised Face Flat Face
Studs Thread
UNC*
Stud
Length *
Qty *
2" 30 (0.35) 60 (0.69) 4 5/8" - 11 2.25" 2
3" 54 (0.62) 108 (1.24) 4 5/8" - 11 2.50" 2
4" 42 (0.48) 78 (0.89) 8 5/8" - 11 2.50" 4
(*) - Blind tapped holes only (1720A). Use standard ANSI stud length for other holes.
TABLE 2 - Valve Weights @ Maximum Settings (Carbon Steel) - Lb. (kg)
Valve Size 1720A 1760A
2" 91 (41) 57 (26)
3" 128 (58) 86 (39)
4" 190 (86) 119 (54)