DUPLEX STACK
MOUNTED SCROLL COMPRESSED
WITH DESICCANT DRYERS
Furnish and install, where
shown on the drawings a duplex stack
mounted prefabricated medical compressed air plant with desiccant air dryers model____________
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 package shall include two oil-less air compressors and associated equipment, one vertical
ASME tank and one duplex control panel. The entire system including the
receiver shall be mounted on a common structural steel stack base. 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.
The medical air compressors
shall be of the totally rotary oil-less scroll design. They
are dynamically balanced for very low noise levels and virtually no vibration.
Each compressor shall be
belt driven by a ____ HP, 3 phase, 60 cycle, ______
volt, 1750
Each air compressor shall
have a capacity of ________
ICFM at 120 PSIG.
The system shall include
individual compressor inline intake filters, discharge check valves of bronze
construction, safety relief valves, bronze intake and discharge flexible
connectors, solenoid valves, isolation valves, air cooled aftercoolers for each
compressor, high discharge temperature shut down switches on each cylinder,
pressure control switches, as well as copper tubing with shut-off cock for
gauge and switches. The system shall include a 120 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
for each pump:
Externally operable circuit
breaker with door interlock, control circuit transformer with fused primary and
secondary coils, H-O-A switch, magnetic starter with 3 leg overload protection,
hour meter and motor running light. Provide the panel with a multiple position
selector switch for selection of normal operation (automatic alternation) or
manual selection of lead and lag pumps if one of the pumps is taken out of
service due to scheduled maintenance. 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 shall be able to start automatically if the lead compressor 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 mounted on the compressor
system base. 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.