Maintenance of valve boxes should be done twice
a year like the valve maintenance schedule for
Maintenance consists of cleaning out debris in the
box, checking for corrosion, checking the elevation of
the top, and checking alignment of the box, so the
valve key can be inserted readily. When the valve box
has corroded and is no longer serviceable, remove it
and replace it with a new unit. When changes in street
or ground level have left the valve box too high or too
low, adjust the height so the cover is at street or ground
VALVE POSITION INDICATORS
Different types of valves have different types of
valve position indicators. Nonrising-stem gate valves
may have indicators on the floor stand. Filter plant
valves may have indicators on the filter operating
table; and butterfly valves, or other valves, used for
flow control or throttling, may have indicator units that
are controlled electrically and look like an ammeter.
The care required depends on the design of the
indicator unit; for example, post indicators require
lubrication quarterly and, position indicators, that are
controlled electrically, should be checked for contact,
wiring, and so on, yearly.
Q5. Floor stands with post indicators are used for
operating what type of valve in what condition?
Q6. A cast-iron pipe, approximately 6 inches in
diameter, has a yoke at the bottom to rest on the
valve bonnet and a cover at street level. This is
what type of valve accessory?
LEARNING OBJECTIVE: Identify types of
water meters and methods of obtaining
Water meters measure the flow of water within a
line to a point of distribution, such as laundries,
housing areas, and so on. There are various types of
water meters. One type is the disk type of volume
meter. This water meter is used chiefly for services
supplied through pipes less than 1 l/2 inches in
diameter, although water meters are made in sizes up
to 6 inches.
Figure 4-16 shows the nutating disk volume meter.
This type of meter is mainly used for individual service
Figure 4-16.Nutating-disk meter.