Val-Matic Rubber-Seated Ball Valve - Manual (Page 4)

4
INSTALLATION REQUIREMENTS
Ball valves are a significant component of any water
pumping system or wastewater system. Valve failure
caused by faulty installation, improper operation, or
maintenance in these systems could result in damage,
down time, and costly repairs. In buried or
underground installations, problems or malfunctions
can result in extensive, costly excavation to correct or
eliminate the problem. Many problems with ball valves
can be traced to improper installation, operation, or
maintenance procedures.
OPERATING PARAMETERS: The valve nameplate
lists the maximum pressures and flow rates within
which the valve is intended to operate. If the system
parameters exceed these values, contact the factory
for assistance.
VALVE TYPE: The nameplate will indicate whether
the valve is a “Single” or “Double” seated valve. Flow
direction as discussed below, is important for single
seat valves.
SHAFT ORIENTATION: It is common to install the
valve with the shaft horizontal. This places the
actuator on the side of the pipeline providing good
access to the handwheel, nut, or cylinder actuator
controls. However, the standard valve is designed to
be installed with the shaft in any orientation.
BURIED SERVICE: The valve should be installed with
the shaft horizontal and the actuator nut directed
upwards. The valve box or extension pipe should be
installed so that the actuator nut and extension stem
turn freely.
SEAT ORIENTATION FOR PIPELINE SERVICE: If
the valve is furnished with a single seat, the normal
flow direction is towards the seat end of the valve.
When the flow stops, the return pressure will be held
by the closed ball and the seat bolts (8) can be
adjusted to provide tight shut off should the seat be
worn or damaged. The nameplate is located on the
seat end valve flange. If the valve is furnished with
double seats, flow direction is not important.
SEAT ORIENTATION FOR PUMP DISCHARGE
SERVICE: On all horizontal pump discharge
applications (Figure 4), the seat end should be towards
the pump to allow seat adjustment with system
pressure against the ball (Figure 4). If the valve is
furnished with double seats, flow direction is not
important.
VALVE SUPPORT: The valve is designed with
integrally cast pads for lifting and supporting the weight
of the valve on a suitable hanger, support, or concrete
pier. The support system should be designed to
support the weight of the valve and not the axial motion
of the piping system, see Figure 5.
FLANGED ENDS: AWWA Class 150 flanged valves
should be mated to ANSI Class 125# flat-faced flanges
equipped with resilient gaskets. When ring gaskets are
used, the bolt material shall be ASTM A307 Grade B or
SAE Grade 2 Carbon Steel. Higher strength bolts may
only be used with full-face gaskets.
FIGURE 4. Flow Direction for Pump Discharge
FIGURE 5. Support Valve Weight
FIELD TESTING
When rubber-seated ball valves are used to isolate
sections of a line for testing, it is important to realize
that these valves are designed or factory adjusted to
hold rated pressure only. If single seated, they hold
pressure in one direction only. Also, test pressures
above valve rated pressure may cause leakage past
the rubber seat and damage to the valve. In order to
NOTE: Adjust and test valve prior to backfill.