13. Pumps:
Water for operating the elevators shall be supplied by two (2) electrically driven centrifugal pumps, drawing from an open suction tank and discharging into two (2) pressure tanks with the necessary pipe connections to the elevator control valves. Each pump shall be the equivalent of The Worthington Pump and Machinery Company's Type 6-UB-1 Volute Pump, and shall have operating characteristics approximately in accordance with the following table when running at seventeen hundred and fifty (1750) R.P.M.
Gauge Pressure Gallons Per Minutes Brake H.P.
205 1000 190
202 1200 210
197 1500 230
181 1800 250
168 2000 260
14. Pumps:
Each pump shall be driven by a three-phase squirrel cage motor, developing two hundred and fifty (250) H.P. at seventeen hundred and fifty (1750) R.P.M. Motors shall be designed to develop their full rated horse power for a period of one hour with a temperature rise not to exceed fifty (50°) decrees C. Motors shall be of approved manufacture.
15. Motor Starters:
Automatic motor starters shall be provided. Starters shall be of the resistance type and shall bring the motor from rest to full speed in not more than fourteen (14) seconds. Inrush peaks shall not be greater than one hundred and fifty (150) percent of the normal full load running current, and the interval between peaks shall not be less than one second. The starters shall he specially designed to suit the space available in the pump-room and, if necessary, the resistance grids shall be suspended from the pump-room ceiling. Each control panel shall include approved overload circuit breakers and no-voltage protection. An automatic pressure switch shall be provided for starting and stopping the motors at the desired limits of pressure. Starters shall be so arranged that one motor is brought to full speed before the second motor is started.
16. Pump Mounting:
Each pump with its driving motor shall be mounted on a bed plate of cast iron or welded structural steel. Bed plate shall be of sufficient rigidity to maintain perfect alignment at all times. Motor and pump shall be connected by means of an approved flexible coupling. The trench provided in the pump-room floor, as indicated, shall be lined with two inch (2") thick natural cork. The cork shall be covered with tarred paper to receive a concrete foundation pier, by others, extending approximately twelve (12") inches above the pump-room floor. The elevator contractor shall submit approved detail drawings for the foundations.
17. Piping:
All connections between pumps, pressure tanks and elevator control valves shall be "extra-strong" lap welded black steel pipe. Fittings and valves shall be American Standard extra heavy for two hundred and fifty (250) pounds pressure. All screwed connections shall be made tight without caulking.
18. Return connections between elevator control valves and suction tank, and suction connections between tank and pumps shall be standard "full weight lap welded black steel pipe". Fittings and valves shall be American Standard for one hundred and twenty-five (125) pounds pressure. Joints shall be made tight without caulking.
19. Provisions shall be made for draining the entire hydraulic elevator system into the pipe tranches.
20. Air Compressor:
This Contractor shall furnish and install an electrically driven single-stage water-cooled air compressor. Compressor shall deliver approximately thirty-five (35) cubic feet of free air per minute at a maximum working pressure of two hundred (200) pounds. The compressor shall be connected to the elevator pressure tasks as indicated on drawings. A separate air receiver for use with stage effects shall be installed under the pump-room stairway. Receiver shall have a a capacity of approximately thirty (30)cubic feet, and shall be provided with an automatic pressure switch for starting and stopping compressor within the desired limits of pressure.