DUPLEX MODULAR SCROLL COMPRESSED
WITH DESICCANT DRYERS
Furnish and install, where
shown on the drawings a duplex
modular prefabricated medical compressed air plant with desiccant air dryers
model 3DOHS15MS120D as manufactured by EMSE Corporation,
The unit furnished shall be a standard catalog item of
the supplier regularly engaged in the business of providing packaged systems
for hospitals and laboratories and shall meet and exceed the requirements of
NFPA 99.
The system shall consist of two skids: the first skid shall
include the scroll air compressors, associated equipment and a control panel, the second skid shall include a vertical ASME tank
and a dual air treatment system with desiccant air dryers. The only field
connections required will be system intake, exhaust and power connection at the
control panel. All components shall be completely pre-piped and pre-wired to
single-point service connections. All interconnecting piping and wiring shall
be completed and operationally tested prior to shipment. Provide liquid tight
conduit, fittings and junction boxes for all control and power wiring. After the test the system shall be separated
into 34" modules for ease of installation.
The medical air compressors shall be of the totally
oil-less rotary scroll design. They are dynamically balanced for very low noise
levels and virtually no vibration.
Each compressor module shall be belt driven by a 3
phase, 60 cycle, ______ volt, 1750
The NFPA system capacity with reserve compressor on
stand-by shall be 96 ICFM at 120 PSIG.
The system shall include compressor inline intake
filters, discharge check valves of bronze construction, safety relief valves,
bronze intake and discharge flexible connectors, isolation valves, air cooled
aftercoolers for each compressor, high discharge temperature shut down
switches, pressure control switches, as well as copper tubing with shut-off cock
for gauge and switches. The system shall include a 200 gallon pressure storage
tank of ASME construction rated for 200
The system shall include a UL listed control panel in
a NEMA 12 enclosure with the following accessories:
Externally operable circuit breaker with door
interlock, control circuit transformers with fused primary and secondary coils,
H-O-A switches, magnetic starters with 3 leg overload protection, hour meters
and motor running lights. Provide audible and visual local alarm (complete with
indicating lights and individual sets of auxiliary contacts wired to the
terminal strip for remote alarm indication) for the following: compressor temperature malfunction and reserve compressor in use.
Provide manual reset for thermal malfunction shut-down. All control and alarm
functions shall remain energized while any compressor in the system remains
electrically on-line. The lag compressor module shall be able to start
automatically if the lead compressor module fails to operate.
A completely packaged NFPA 99 and NEC compliant
assembly featuring dual desiccant air dryers, dual 0.5 micron pre-filters, dual
0.5 micron after-filters, line pressure regulating valves, dew point monitor,
CO monitor and other accessories required to meet and exceed the current code
requirements shall be provided as part of the receiver skid. All components
shall be completely pre-piped and pre-wired to single-point service
connections.
There shall be two identical banks of air treatment equipment, piped in parallel and provided with valves to by-pass either filter set for element replacement, maintenance and repair work on one of the sets while still treating medical compressed air through the other set without any sacrifice in air quality. Each bank consists of three stages of treatment.
The first stage is a prime efficiency
coalescer with particle removal down to 0.5 micron with 99.9999% retention.
This filter removes aerosols and solid particles. The filter is equipped with
electronic drain and element change indicator.
The second stage is a desiccant heatless
air dryer, equipped with purge control. Pressure dew point of 0oF is
attained by directing the flow of saturated compressed air over a bed of desiccant
which is contained in two separate but identical "twin" towers.
Built-in purge saver control will automatically minimize and adjust the amount
of purge air to match the variable air flow. The dry compressed air is
discharged from the "on line" tower into the third stage.
The third stage is a prime efficiency
particulate afterfilter with particle removal down to 0.5 micron. The after
filter element is provides high particle retention, low pressure drop and long
element life.
Downstream pressure regulators will
maintain constant discharge pressure of 55 PSIG (field adjustable).
Digital dew point and CO monitors with
alarm set points at +390F and
10 PPM are provided with dry contacts for connection to remote alarm panels. A
"demand check" for maintenance is included per current NFPA 99 for
each instrument.
The compressed air system shall be guaranteed in
writing by the manufacturer for a period of 12 months from the date of start-up
or 18 months from the date of shipment (whichever comes first) against defects
in design, materials, or construction. In addition, the compressors are
guaranteed for 36 months from the date of shipment.
The service of a factory trained representative shall
be made available at the jobsite to check installation, start-up and instruct
operating personnel in the proper operation and maintenance.