DeZURIK
APCO CVS-EDV Swing Check Valves
February 2016
Page 5
D12042
Installation
(Continued)
•
Before installation, remove foreign material such as weld spatter, oil, grease, and dirt from the
pipeline.
•
Prepare pipe ends and install valves in accordance with the pipe manufacturer’s instructions for
the joint used.
Do not deflect the pipe-valve joint. Minimize bending stresses in the valve end
connection with pipe loading.
If excessive seat leakage occurs during start-up, recheck the installation and
eliminate any distortion to the valve body.
•
Ensure the valve and pipeline flanges are concentric to ensure proper flange sealing and seat
leakage control.
•
Tighten the flange bolts or studs in a crisscross pattern a minimum of four stages.
Fusion/Powder Coated Valves
Valves with fusion/powder coated exterior paint require flat washers to be installed
under the flange nuts when installing the valve to the pipeline flange to prevent the
paint from cracking or chipping.
Maintenance
It is suggested that these valves, which do not require routine scheduled maintenance, be included as
part of the normal facility equipment inspections for any malfunction while under normal usage
conditions.
Shaft Packing Adjustment
Packing adjustment may be needed to optimize packing life on initial start-up.
These valves may open or close, swinging the counterweight/spring lever arm without
warning due to flow changes from pumps starting and stopping. Servicing or working
around these valves while the pipeline is under pressure can cause personal injury or
equipment damage.
Workers must be cautious when working around these valves. Relieve pipeline pressure
and lockout the pumps before servicing the valve.
Tighten the Gland Nuts (A26) (see Figure 3) evenly only until the packing leak stops.
Caution:
Do not over-tighten Packing Gland. Valve can remain open during operation if packing is too
tight. After packing adjustments are made and pipeline is pressurized, visually inspect valve stroke to
ensure proper operation.
Note:
Do not continue tightening after leak stops. If packing leak cannot be stopped by tightening the
gland nuts, the packing must be replaced.