substitution request - Alliance Construction Solutions

PART 3 – EXECUTION
3.01 EXAMINATION:
7. For two-position service, the actuator shall be rated at a 20% duty cycle (i.e., 12
minutes extended duty in every hour, or alternatively, one complete cycle every two
minutes). For frequent cycling and modulating service, the actuator shall be rated
for continuous duty, capable of operating 100% of the time at an ambient
temperature of 104ºF (40°C).
8. The actuator shall have a permanently lubricated, self-locking gear train. Motor
brakes shall not be required to maintain desired valve position. Levers or latches
shall not be required to engage or disengage the manual override. Mechanical
travel stops, adjustable to 15º in each direction of 90º rotation, shall be standard,
as well as two adjustable travel limit switches with electrically isolated contacts.
Additional adjustable switches shall be provided where required to meet the
sequence of operation.
9. The motor shall have Class B insulation capable of withstanding locked rotor
current for 25 seconds without overheating. Wiring shall also have Class B
insulation. An auto-reset thermal cut-out protector shall be embedded in the
motor windings. The motor shall be UL recognized and CSA approved.
Disassembly of gears shall not be required to remove the motor.
10. Materials:
Project No.: 10145
550 15 th Street Dual Brand Hotel
03/16/2012
a. The electric actuator shall have a pressure die-cast, hard-anodized
aluminum base and cover. The compound gear shall be made of diecast,
hard-anodized aluminum or steel. An alloy steel worm gear shall be
provided for manual override and torque limiting. Bearings for gears
shall be of the ball and needle type; bronze bearings shall be used on the
shafting parts.
11. Electric Valve Actuator Accessories:
a. Provide thermostatically controlled heaters for all exterior valves.
b. Provide potentiometer or 4-20 mA transmitter for providing continuous
feedback of actuator position where required to meet the sequence of
operations.
c. Provide an electronic servo amplifier and speed control module capable
of accepting a 0-5 Kohm, 4-20 mA DC or other input signal for all
modulating control valves.
A. Install valves in accordance with manufacturer’s instructions, including recommended
lubrication.
B. Examine valve interior through the end ports for cleanliness, freedom from foreign matter
and corrosion. Remove special packing materials, such as blocks used which prevent disc
movement during shipping and handling.
C. Actuate valve through an open-close and close-open cycle. Examine functionally
significant features, such as guides and seats made accessible by such actuation.
Following examination, return the valve closure member to the position in which it was
shipped.
23 0523 - 7 GENERAL-DUTY VALVES FOR
HVAC PIPING