2.22.2.10
Piping
Pipes shall be of corrosion-resistant material, and have a smooth internal
surface. Plastic pipe shall be acrylonitrile-butadiene-styrene (ABS)
conforming to ASTM D 1527 or polyvinyl chloride (PVC) conforming to ASTM D
1785. Solvent cement for ABS plastic pipe fittings shall conform to ASTM D
2235. PVC plastic pipe fittings shall conform to ASTM D 2466, and solvent
cement shall conform to ASTM D 2564. Fittings, supports and joint assembly
shall be of approved type. The assembled piping system shall be suitable
for 17 kPa 5 inch Hg vacuum. Fittings shall be of DWV long-radius type.
Coupling, union, and other disconnecting fittings shall be readily
accessible at all times. The most distant end of the main trunk line from
the central filter-separator shall terminate with an air volume relief
valve.
2.22.2.11
Air Volume Relief Valve
The air volume relief valve shall be mechanically operated, requiring no
electrical power. The valve shall operate automatically, sensing negative
pressure in the system and opening and closing proportionately to maintain
designed air capacity to the vacuum producer regardless of the number of
inlets on-line. Valve shall be equipped with silencer to attenuate air
noise to 85 dB or less.
2.22.2.12
Vacuum Inlets
User inlets for technicians' benches shall be 32 mm 1-1/4 inches ID and for
fixed-equipment locations, 40 mm 1-1/2 inches ID, with removable friction
fit adapters sized to receive 80 mm 3 inch ID flexible hose. Adapters
shall provide an airtight seal when inserted into the vacuum inlet. Inlets
shall have attached pivot or hinge-mounted doors. When closed, the doors
shall provide an airtight seal to close off the vacuum inlet; when open,
they shall not interfere with insertion of the adapters with 80 mm 3 inch
ID hose attached.
2.22.2.13
Spare Parts
A vacuum producer bearing and belt kit shall be delivered with the system.
The kit shall include one set each of exhauster bearings and replacement
drive belts, all the same size and design as those supplied with the
turbo-exhauster. The repair kit shall also include complete installation
instructions for all its items.
2.22.3
Environmental-Janitorial Vacuum System (EJVS)
2.22.3.1
Vacuum Source
The vacuum producers furnished for the HVE system shall serve as the vacuum
source for the EJVS.
2.22.3.2
Central Dry Separator
The central separator shall be a freestanding dry unit of heavy-gauge steel
and all-welded construction. The separator chamber shall be the cyclonic
type and shall effectively separate and trap all particulate matter
contained in the vacuum input. The internal configuration of the separator
shall be such that air leaving the cyclonic chamber shall be directed
upward through a filter bag to effect final cleaning of the air before its
SECTION 15405A
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