2010 Construction and Material Specifications - Ohio Department of ...

567
638.13
Install valve boxes on all buried valves. Center the valve box and set it in a
vertical position directly over the valve nut in such a manner that the box does not
transmit shock or stress to the valve. Set the base of the valve box first, and
support it with a minimum backfill, hardwood blocks, or a Styrofoam collar at
least 2 inches (50 mm) in thickness. Do not allow the base to rest directly on the
valve or main. Use valve boxes that are two or three piece boxes with covers.
When necessary, furnish extension sections. Carefully tamp backfill around the
valve box to a distance of 3 feet (1 m) on all sides or to the undisturbed face of the
trench if closer. Set the valve box cover flush with the ground line or finished
paved surface.
Installation methods for valves and equipment include the following.
A. Gate Valve and Valve Box. Install gate valves directly in new mains or by
means of a cutting-in sleeve in existing mains where maintenance of a continuous
supply of water is not mandatory. Where it is mandatory not to interrupt the water
supply, the Contractor may provide a branch to an existing main with a gate valve
installed by means of a tapping sleeve.
B. Inserting Valve and Valve Box. Install inserting valves in existing water
mains where it is mandatory not to interrupt the water supply.
Assemble the sleeve around the existing main through which water is
flowing under pressure. Bolt the equipment to the sleeve, drill a hole through the
existing main walls, and insert the valve, according to the manufacturer’s
recommendations.
C. Cutting-In Sleeve, Valve, and Valve Box. Use cutting-in sleeves to install
a gate valve in an existing main, without breaking pipe joints, where it is
permissible to interrupt the flow for a short period of time. Install the valve by
cutting an exact length of pipe from the existing main according to the
manufacturer’s recommendation.
Assemble the cutting-in sleeve, its glands and gaskets, and the cutting-in
valve over the cut ends of the existing pipe according to the manufacturer’s
recommendations.
D. Tapping Sleeve, Valve, and Valve Box. Where it is mandatory not to
interrupt the water supply in an existing main and the branch is 4-inch (100 mm)
or larger provide tapping sleeves.
Bolt the tapping sleeve around the existing main, assemble the tapping valve,
and drill a hole through the main wall, according to the manufacturer’s
recommendations.
E. Tapping Saddle and Corporation Stop. Use corporation stops to provide
individual service connections to mains. Ensure that the stops permit a shut-off of
the service flow. Either assemble the stops directly to mains by means of a tap
tool providing a tapped hole, or use a tapping saddle. Fasten the saddle around the
main and drill a hole into the main by an attached drilling machine, then remove
the machine and screw the stop into the saddle. Do not use corporation stops
larger than 2 inches (51 mm) in size and locate them approximately 60 degrees
from the top of the main.