Varec 2500, Installation And Operation Manual

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Varec, Inc. 9
Varec recommends guide wire installations for the 2500 ATG with standard guide wire centers
of 17" (432 mm) when a standard 14.5" (368 mm) diameter (Type 316 stainless steel hollow
shell) float is used. Guide Wires provide stability for the float during turbulent conditions and
provide increased accuracy by reducing the horizontal movement of the float across the
surface of the product. The guide wires should be installed centered and free of twists or kinks.
Check the movement of the float for friction or impended movement before final operation.
Varec provides two options for tank bottom, guide wire anchors, in-service and out-of-service
anchors. An anchor that can be welded to the tank bottom is used when the tank is
out-of-service (Part #AA1025). A weight can be used as an alternative when the installation is
performed while the tank is in service (Part #BA4481).
Varec top guide wire anchors can be screwed or welded into the tank roof, maintenance hatch,
or manhole cover.
Support Brackets
“A” frame brackets support the conduit (pipework) that carries
the tape. These brackets can be welded or bolted to the tank
and should be placed at regular intervals (approx. 10ft or 3
meters) to provide uniform support. The pipework should be
held rigidly in place and correctly aligned so that the tape does
not touch or rub the internal pipework.
The steel pipe support bracket is used on the side of the tank
(Part #B5643-003). The upper support bracket assembly is
used at the tank top (Part #BM717).
Figure 1: Support brackets and conduit shown on an external
floating roof tank
Conduit (Pipework) and Couplings
Plan the pipe routing and make sure you have the required conduit, elbows, and other
materials needed. Couplings and unions can be used to easily connect sections of pipework
together without welding. They also provide a means to maintain the pipework, tape and
gauge head. Vertical runs must be plumbed to be perpendicular to prevent the tape from
binding inside the pipe.
The pipe carrying the perforated tape must be attached to the tank by welding the supplied
brackets. If the environment is such that welding cannot be performed, the user can construct
a support structure with 3-inch (76 mm) pipe or conduit close to the outside of the tank. The
brackets can be welded to the support structure at another location, if necessary, and the pipe
structure assembled at the tank site.