THEATRE NO.10
of the
METROPOLITAN SQUARE DEVELOPMENT
New York City
S P E C I F I C A T I O N S
for
STAGE EQUIPMENT
CONTENTS -- Click on the desired section, or scroll down to view the complete SPEC.
TITLE PAGE OF ORIGINAL SPEC
BAND CAR, MOTORIZED
CONTOUR CURTAIN
CONTOUR CURTAIN COUNTERWEIGHT SET
COUNTERWEIGHT SETS, MANUAL
COUNTERWEIGHT SETS, MOTORIZED
CYC, MOTORIZED SET
FIRE CURTAIN, GENERAL
FIRE CURTAIN, OPERATION
FIRE CURTAIN, MOTORIZED SET
FIRE CURTAIN, FOR SUB-BASEMENT
FOOTLIGHTS, MAIN, DISAPPEARING AND TILTING MECHANISM
FOOTLIGHTS, CYC TROUGH COVERS, MOTORIZED
LIGHT BRIDGES E-F-G-H, MOTORIZED SETS
LIGHT BRIDGES, SIDE
LIGHT TOWERS, PORTABLE
ORGAN CONSOLE CARS
PICTURE SHEET MASKING, MOTORIZED
PICTURE SHEET, UPSTAGE
PICTURE TRAVELER ("ACT CURTAIN") MOTORIZED MASKING AND RIGGING
REVOLVING STAGE,MOTORIZED
REVOLVING STAGE CYCLORAMA RIGGING
SECOND PROSCENIUM, MOTORIZED MASKING ON ROLLERS
STAGE ELEVATOR SIZE, TRAVEL, AND CAPACITY
STAGE ELEVATOR PUMPING PLANT
STAGE ELEVATOR PLUNGERS AND CYLINDERS
STAGE ELEVATORS, EQUALIZERS
STAGE ELEVATORS, CONTROL
STAGE ELEVATOR PIT FENCE, RIGGING
SIDE TABS, COUNTERWEIGHT SETS FOR ELEX
STEAM CURTAIN
TRAVELER TRACKS ("DRAW CLOSE-IN TRACKS")
MISCELLANEOUS
AIR EFFECT LINE
CAPSTAN WINCH
GRAND FOYER CHANDELIERS, RIGGING
GRAND FOYER DRAPE, RIGGING
HORN RIGGING (ALTERNATE)
MICROPHONE HOISTING REEL
SPOT AND ARC LAMP SUPPORTS
STAGE ELEVATOR GUIDE COVERS
STAGE ELEVATOR LIMIT SWITCHES
GENERAL CONDITIONS
1. The General Conditions attached hereto form an integral part of the contract for this work and all conditions contained therein shall be binding upon this Contractor and shall govern the work.
NOTICE TO BIDDERS
2. Before submitting his proposal, each bidder shall examine all drawings relating to this work and shall become fully informed as to the extent and character of the work required and its relation to other works in this building. No consideration will be granted for any alleged misunderstanding of the materials to be furnished or work to be done, it being understood that the tender of a proposal carries with it the agreement to all items and conditions referred to herein and in the General Conditions or indicated on the accompanying drawings.
VERIFY EXISTING CONDITIONS
3. This Contractor, before commencing work shall verify all governing dimensions at the building and shall examine all adjoining work on which his work is in any way dependent for its perfect efficiency according to the intent of this specification.
DESIGNATIONS HEREIN
4. “Owner”
Metropolitan Square Corporation
5. “Architects”
Reinhard & Hofmeister
Corbett, Harrison & MacMurray
Hood & Fouilhoux.
6. “Managers”
Todd,Robertson,Todd Engineering Corporation
Todd & Brown, Inc.
7. “Builder”
John Lowry, Inc.
8. “Contractor”
The Contractor for the work herein specified.
Metropolitan Square Corporation
5. “Architects”
Reinhard & Hofmeister
Corbett, Harrison & MacMurray
Hood & Fouilhoux.
6. “Managers”
Todd,Robertson,Todd Engineering Corporation
Todd & Brown, Inc.
7. “Builder”
John Lowry, Inc.
8. “Contractor”
The Contractor for the work herein specified.
WORK NOT INCLUDED
9. The following items are not included under this contract, and are to be performed by the contractors for the various trades in collaboration with and under the direction of the contractor for Stage Equipment:
(a) Foundations and Trenches for pumps for Hydraulic Stage and Orchestra Pit Elevators.
(b) Means of drainage of pipe trenches for Hydraulic Elevator System.
(c) Suction Tank.
(d) Pressure Tanks.
(e) Excavation for cylinder assemblies, foundations, piers, etc.
(f) Furnishing and setting sand and grout around above.
(g) Pipe liners for equalizers and guide system for Hydraulic Elevators, and excavation for same.
(h) Power service to all motors, control panels.
(i) All wiring necessary for control of the revolving stage.
(j) Finished openings in Stage Floor, Basement and Sub-basement.
(k) All required terraced platforms and ornamental Fascias for the Band Car.
(l) All required wiring including control connections for Organ Console Cars.
(m) All electric wiring necessary for operation of the Disappearing Footlights.
(n) Illuminating lamp strips and color frames.
(o) Wood covers and electric wiring for Cyclorama Light Troughs.
(p) Sanding and finishing floors of Orchestra and Stage Elevators.
(q) Excavations of pits for Orchestra and Stage Elevators.
(r) Preparation of Foundations for Orchestra and Stage Elevators.
(s) Furnishing and installing a11 anchors for the Smoke Pockets and guides of Protective Fire Curtains.
(t) All electric wiring except in connection to elevators, motors, control panels, limit switches, lights, organ consoles, footlights, etc., hereinafter specified as "By Others" in this specification.
(u) All painting, sizing and decoration of Protective Fire Curtains.
(v) Furnishing and erection of Picture Sheet.
(w) Painting of Cyclorama.
(x) Lamps, wiring and control for the Star Effects on the back of the Cyclorama.
(y) Cat walks over auditorium ceiling and at spot and arc light supports.
(z) Material Cyclorama.
(aa) Furnishing and Installation of Picture Sheet.
(bb) Masking and Rear Projection Sheet.
(cc) Control Valve and Pipe for Steam.
(dd) Drain outlet for Steam Curtain.
(ee) Wood covering for Steam Curtain.
(ff) Wall Anchors for Smoke Pockets - Steel Curtain.
(gg) Painting and decoration of Steel Curtain and Metal Guards.
(a) Foundations and Trenches for pumps for Hydraulic Stage and Orchestra Pit Elevators.
(b) Means of drainage of pipe trenches for Hydraulic Elevator System.
(c) Suction Tank.
(d) Pressure Tanks.
(e) Excavation for cylinder assemblies, foundations, piers, etc.
(f) Furnishing and setting sand and grout around above.
(g) Pipe liners for equalizers and guide system for Hydraulic Elevators, and excavation for same.
(h) Power service to all motors, control panels.
(i) All wiring necessary for control of the revolving stage.
(j) Finished openings in Stage Floor, Basement and Sub-basement.
(k) All required terraced platforms and ornamental Fascias for the Band Car.
(l) All required wiring including control connections for Organ Console Cars.
(m) All electric wiring necessary for operation of the Disappearing Footlights.
(n) Illuminating lamp strips and color frames.
(o) Wood covers and electric wiring for Cyclorama Light Troughs.
(p) Sanding and finishing floors of Orchestra and Stage Elevators.
(q) Excavations of pits for Orchestra and Stage Elevators.
(r) Preparation of Foundations for Orchestra and Stage Elevators.
(s) Furnishing and installing a11 anchors for the Smoke Pockets and guides of Protective Fire Curtains.
(t) All electric wiring except in connection to elevators, motors, control panels, limit switches, lights, organ consoles, footlights, etc., hereinafter specified as "By Others" in this specification.
(u) All painting, sizing and decoration of Protective Fire Curtains.
(v) Furnishing and erection of Picture Sheet.
(w) Painting of Cyclorama.
(x) Lamps, wiring and control for the Star Effects on the back of the Cyclorama.
(y) Cat walks over auditorium ceiling and at spot and arc light supports.
(z) Material Cyclorama.
(aa) Furnishing and Installation of Picture Sheet.
(bb) Masking and Rear Projection Sheet.
(cc) Control Valve and Pipe for Steam.
(dd) Drain outlet for Steam Curtain.
(ee) Wood covering for Steam Curtain.
(ff) Wall Anchors for Smoke Pockets - Steel Curtain.
(gg) Painting and decoration of Steel Curtain and Metal Guards.
WORK INCLUDED
10. Except as herein noted under "Work Not Included", the work under this contract shall include all labor, materials, apparatus, etc. required to furnish and install complete Stage Equipment as shown on the drawings and hereinafter specified consisting in general of the following:
(a) Hydraulic Stage and Orchestra Pit Elevators including Revolving Stage on Stage Elevator.
(b) Motor Propelled Band Car.
(c) Organ Console Cars.
(d) Disappearing Footlight Mechanism.
(e) Air Effect Line.
(f) Operating Mechanism for Cyclorama Light Trough Covers.
(g) Protective Fire Curtain.
(h) Act Curtain Rigging.
(i) Counterweight System - 75 sets including Two (2) sets for Borderlights D and K and Five (5) sets for Close-in Draw Curtain Tracks.
(j) Border Light Baffles
(k) Heavy Duty Portable Electric Winch
(l) Ten (10) Electrically Operated Counterweight Sets.
(m) Contour Curtain.
(n) Cyclorama.
(o) Second Proscenium Rigging.
(p) Light Bridges and Rigging.
(q) Portable Light Towers.
(r) Spot and Arc Lamp Supports.
Proscenium Alcove -- Arch and Ceiling
(s) Side Light Bridges, Railings and Posts - Platforms, Ladders and Rigging.
(t) Rigging for Material Cyclorama for Revolving Stage.
(u) Magnascope Picture Sheet and Effect Frame.
(v) Horn Rigging.
(w) Frame of Rear Projection Sheet.
(x) Steam Curtain.
(y) Steel Curtain Sub-Basement.
(z) Two (2) Main Fixtures in Lobby
(aa) Equipment for Hanging Drapes in Grand Foyer.
(bb) Microphone Hoisting Reel.
(cc) Covers for Elevator Guides.
(a) Hydraulic Stage and Orchestra Pit Elevators including Revolving Stage on Stage Elevator.
(b) Motor Propelled Band Car.
(c) Organ Console Cars.
(d) Disappearing Footlight Mechanism.
(e) Air Effect Line.
(f) Operating Mechanism for Cyclorama Light Trough Covers.
(g) Protective Fire Curtain.
(h) Act Curtain Rigging.
(i) Counterweight System - 75 sets including Two (2) sets for Borderlights D and K and Five (5) sets for Close-in Draw Curtain Tracks.
(j) Border Light Baffles
(k) Heavy Duty Portable Electric Winch
(l) Ten (10) Electrically Operated Counterweight Sets.
(m) Contour Curtain.
(n) Cyclorama.
(o) Second Proscenium Rigging.
(p) Light Bridges and Rigging.
(q) Portable Light Towers.
(r) Spot and Arc Lamp Supports.
Proscenium Alcove -- Arch and Ceiling
(s) Side Light Bridges, Railings and Posts - Platforms, Ladders and Rigging.
(t) Rigging for Material Cyclorama for Revolving Stage.
(u) Magnascope Picture Sheet and Effect Frame.
(v) Horn Rigging.
(w) Frame of Rear Projection Sheet.
(x) Steam Curtain.
(y) Steel Curtain Sub-Basement.
(z) Two (2) Main Fixtures in Lobby
(aa) Equipment for Hanging Drapes in Grand Foyer.
(bb) Microphone Hoisting Reel.
(cc) Covers for Elevator Guides.
STAGE ELEVATORS, SIZE, TRAVEL AND CAPACITY
11. This Contractor shall furnish and erect, four (4) elevators, one approximately seventy (70'-0") feet long by sixteen (l6'-0") feet maximum width, shaped to conform to the orchestra pit; and on the stage,
two, approximately seventy (70'-0") feet long by sixteen (16'-0") feet
wide, and one seventy (70'-0’) feet long by twelve feet seven inches (12'7") wide. The elevator in the orchestra pit shall travel from sub-basement level, elevation plus twenty-eight feet two inches (28'2") to stage level, elevation plus fifty-five (55'-0") feet. The three stage elevators shall travel from sub-basement level, elevation plus twenty-eight feet two inches (28'2") to a point thirteen feet two inches (13'-2") above stage elevation plus sixty-eight feet two inches (68'2").
12. Each elevator shall be capable of lifing a live load of twenty-eight thousand (28,000) pounds at a normal operating speed of thirty (30'0") feet per minute.
12. Each elevator shall be capable of lifing a live load of twenty-eight thousand (28,000) pounds at a normal operating speed of thirty (30'0") feet per minute.
STAGE ELEVATORS, PUMPING PLANT
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.
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.
STAGE ELEVATORS, PLUNGERS AND CYLINDERS, PLATFORMS AND MASKING
21. Each elevator shall be operated by two (2) plungers. Plungers shall be twenty (20) inches diameter and shall be constructed from steel pipe or tubing with a three-fourth (3/4") inch thick wall. The outside of the plungers shall be accurately turned and polished. Where joints are necessary, they shall be made by a closely fitting internal sleeve, screwed into each piece of tubing, and made tight with hydraulic cement. The sleeve shall be of sufficient length to develop the full strength of the tubing.
22. At the head of each plunger there shall be attached a cast steel platten, for attaching the structural steel platform members. Plattens shall be black open-hearth steel castings, free from defects and shall be carefully annealed before machining.
23. To the bottom of each plunger there shall be attached a cast stool plug, with a projecting flange to provide a positive stop at the top limit of travel.
24. Each cylinder shall be built of twenty-four (24”) inch 0.D. steel pipe with a welded head at the lower end. The upper cylinder head and stuffing box shall be of close grained gray cast iron, attached to the cylinder by a belting flange, set flush with the elevator pit floor. The complete cylinder assembly shall be tested at four hundred (400) pounds water pressure and all leaks corrected before installation, and the pipe shall receive two (2) coats of asphaltum, applied hot.
25. Plunger packing and Control Piping:
Plunger packing shall be of an approved non-compressing type and arranged for easy replacement. Connections to control valves shall be five (5) inch extra strong pipe with extra heavy two hundred and fifty (250) pound fittings.
26. Location and Installation of Cylinder Assemblies:
Cylinder assemblies shall be accurately located in the holes for their reception, and the space around then closely pocked with sand to within eighteen inches (18") of the top. The remaining space shall then be filled with grout.
27. Platform Frames:
Each platform shall be supported on a structural steel frame, extending the full length of the platform. The floor system shall consist of suitable beams framed to girders. The framing of the floor beams shall be such that full provision shall be made for the revolving stage, as hereinafter described, and sufficient headers shall be used to develop the lateral stiffness of the girders. All connections other than those of the floor system shall be hot riveted with rivets not less than seven-eighth (7/8") inch diameter.
28. Wood Flooring:
Wood nailing strips shall be attached to the floor beams for attaching wood flooring.
29. Floor shall be first grade hard maple, fifty-three thirty-seconds (53/32") inches by two and one-quarter (2-1/4") inches, dressed and matched and end matched T. & G., in minimum lengths of four (4'-0") feet, and to meet the requirements of the Maple Flooring Manufacturers Association. The platform shall be designed to support a uniformly distributed live load of one-hundred (100) pounds per square foot, and under the normal working load of twenty-five (25) pounds per square foot, the maximum deflection shall not exceed one-eighth (1/8") inch.
30. All steel work shall receive one (1) shop coat of red lead paint.
31. The elevator contractor shall furnish a sheet metal guard five (5') feet deep around the underside of each elevator, and shaped to form a beveled toe guard at the point where it joins the platform. The canvas masking drop shall be attached to the lower edge of the sheet metal extending eight (8') feet below to completely mask in the openings when the elevators are at high level; also to have telescope-braced brackets back of canvas to keep the canvas rigid, this applies to both sides and both ends of the elevators.
22. At the head of each plunger there shall be attached a cast steel platten, for attaching the structural steel platform members. Plattens shall be black open-hearth steel castings, free from defects and shall be carefully annealed before machining.
23. To the bottom of each plunger there shall be attached a cast stool plug, with a projecting flange to provide a positive stop at the top limit of travel.
24. Each cylinder shall be built of twenty-four (24”) inch 0.D. steel pipe with a welded head at the lower end. The upper cylinder head and stuffing box shall be of close grained gray cast iron, attached to the cylinder by a belting flange, set flush with the elevator pit floor. The complete cylinder assembly shall be tested at four hundred (400) pounds water pressure and all leaks corrected before installation, and the pipe shall receive two (2) coats of asphaltum, applied hot.
25. Plunger packing and Control Piping:
Plunger packing shall be of an approved non-compressing type and arranged for easy replacement. Connections to control valves shall be five (5) inch extra strong pipe with extra heavy two hundred and fifty (250) pound fittings.
26. Location and Installation of Cylinder Assemblies:
Cylinder assemblies shall be accurately located in the holes for their reception, and the space around then closely pocked with sand to within eighteen inches (18") of the top. The remaining space shall then be filled with grout.
27. Platform Frames:
Each platform shall be supported on a structural steel frame, extending the full length of the platform. The floor system shall consist of suitable beams framed to girders. The framing of the floor beams shall be such that full provision shall be made for the revolving stage, as hereinafter described, and sufficient headers shall be used to develop the lateral stiffness of the girders. All connections other than those of the floor system shall be hot riveted with rivets not less than seven-eighth (7/8") inch diameter.
28. Wood Flooring:
Wood nailing strips shall be attached to the floor beams for attaching wood flooring.
29. Floor shall be first grade hard maple, fifty-three thirty-seconds (53/32") inches by two and one-quarter (2-1/4") inches, dressed and matched and end matched T. & G., in minimum lengths of four (4'-0") feet, and to meet the requirements of the Maple Flooring Manufacturers Association. The platform shall be designed to support a uniformly distributed live load of one-hundred (100) pounds per square foot, and under the normal working load of twenty-five (25) pounds per square foot, the maximum deflection shall not exceed one-eighth (1/8") inch.
30. All steel work shall receive one (1) shop coat of red lead paint.
31. The elevator contractor shall furnish a sheet metal guard five (5') feet deep around the underside of each elevator, and shaped to form a beveled toe guard at the point where it joins the platform. The canvas masking drop shall be attached to the lower edge of the sheet metal extending eight (8') feet below to completely mask in the openings when the elevators are at high level; also to have telescope-braced brackets back of canvas to keep the canvas rigid, this applies to both sides and both ends of the elevators.
STAGE ELEVATORS, EQUALIZERS, CLUTCHING
32. At each end of each platform frame there shall be attached a structural steel column, extending downward for a distance of approximately forty-two (42’-0") feet. To the outer flanges of these columns, facing the pit walls, there shall be attached suitable members to serve as guide rails, which shall engage continuous stationary guide shoes, extending from the stage floor to the bottom of the elevator pits. To the inner flanges of the columns there shall be attached means for driving the equalizer mechanism.
33. The equalizer mechanism shall be designed to preserve the level of the elevator plungers throughout their travel, regardless of the distribution of the superimposed load on the platform. The variation in level between the two ends of the platform shall not exceed one-eighth (1/8") inch.
34. A system of interconnecting drives shall be installed to permit the operation of the three stage elevators as a single unit when desired, and when so connected there shall not be more than one-eighth (1/8") inch difference in level between any two adjacent sections. The control of the interconnecting mechanism shall be affected from push- buttons located at the master control station.
33. The equalizer mechanism shall be designed to preserve the level of the elevator plungers throughout their travel, regardless of the distribution of the superimposed load on the platform. The variation in level between the two ends of the platform shall not exceed one-eighth (1/8") inch.
34. A system of interconnecting drives shall be installed to permit the operation of the three stage elevators as a single unit when desired, and when so connected there shall not be more than one-eighth (1/8") inch difference in level between any two adjacent sections. The control of the interconnecting mechanism shall be affected from push- buttons located at the master control station.
STAGE ELEVATORS, CONTROL
35. The elevators shall be controlled by three-way valves, arranged to admit water from the pressure tank to the cylinders, and to discharge from the cylinders into the suction tank in the pump-room. The valves shall be designed in accordance with the standard practice for hydraulic elevators, with cup leather packings and graduated port openings.
Packings shall be readily accessible for replacement. The valves shall be absolutely tight when in the closed position to prevent "creeping" of the elevators.
36. Each valve assembly shall consist of six (6) valve units, three for admission and three for discharge. Each unit shall be operated by water pressure admitted to its operating cylinder by a solenoid pilot valve. Speed control of the elevators shall be affected by means of a master switch located at the control station, which shall govern the opening of the individual valve units.
37. Directional control shall be effected by means of push-button operating stations, located on the stage as directed, and shall govern the opening of the admission or discharge group of valves as required. Buttons shall be provided for the High, Stage and Basement and Sub-basement levels, with additional buttons for stopping the elevators at any other level desired. Automatic stops for each elevator corresponding to the levels indicated by the push buttons shall be effected by means of a geared selector switch driven from the equalizing shaft. The opening of the contacts of the selector switch shall close the elevator operating valves corresponding to the direction of travel of the elevator. The selector shall be provided with auxiliary contacts, arranged to operate by-pass valve to automatically correct "creeping" of the elevator due to any small leakage which may occur when the elevator is at stage level, by either admitting or discharging water as required. The leveling device shall be designed to maintain the correct position within one-eighth (1/8") inch.
38. The entire selector device shell be enclosed in a water-tight casing, which shall be readily accessible for inspection and adjustment.
39. The necessary relays and switches for the control of each elevator shall be mounted on slate panels and installed in the pump-room. Wherever necessary, all wiring shall be in water-proof conduit.
40. A system of indicators shall be provided which shall indicate to the elevator operator at all times the relative positions of the elevators, as well as the relative speeds of each elevator.
41. Wiring:
All wiring between push buttons, relays, selectors and pilot valves shall be installed by the elevator contractor, and also wiring from pump motors to starters and automatic pressure switches. Wiring shall conform to the requirements of the National Board of Fire Underwriters, and also the Electrical Code of the City of New York.
36. Each valve assembly shall consist of six (6) valve units, three for admission and three for discharge. Each unit shall be operated by water pressure admitted to its operating cylinder by a solenoid pilot valve. Speed control of the elevators shall be affected by means of a master switch located at the control station, which shall govern the opening of the individual valve units.
37. Directional control shall be effected by means of push-button operating stations, located on the stage as directed, and shall govern the opening of the admission or discharge group of valves as required. Buttons shall be provided for the High, Stage and Basement and Sub-basement levels, with additional buttons for stopping the elevators at any other level desired. Automatic stops for each elevator corresponding to the levels indicated by the push buttons shall be effected by means of a geared selector switch driven from the equalizing shaft. The opening of the contacts of the selector switch shall close the elevator operating valves corresponding to the direction of travel of the elevator. The selector shall be provided with auxiliary contacts, arranged to operate by-pass valve to automatically correct "creeping" of the elevator due to any small leakage which may occur when the elevator is at stage level, by either admitting or discharging water as required. The leveling device shall be designed to maintain the correct position within one-eighth (1/8") inch.
38. The entire selector device shell be enclosed in a water-tight casing, which shall be readily accessible for inspection and adjustment.
39. The necessary relays and switches for the control of each elevator shall be mounted on slate panels and installed in the pump-room. Wherever necessary, all wiring shall be in water-proof conduit.
40. A system of indicators shall be provided which shall indicate to the elevator operator at all times the relative positions of the elevators, as well as the relative speeds of each elevator.
41. Wiring:
All wiring between push buttons, relays, selectors and pilot valves shall be installed by the elevator contractor, and also wiring from pump motors to starters and automatic pressure switches. Wiring shall conform to the requirements of the National Board of Fire Underwriters, and also the Electrical Code of the City of New York.
REVOLVING STAGE, MOTORIZED
42. Revolving Stage:
The elevator platform shall be framed to receive a revolving platform, forty-three feet two inches (43'2") diameter, as indicated on the drawings. The platform shall be divided in three sections so indicated, and when not used as a turntable, it shall become an integral part of the elevator floor.
43. The platform shall be rotated by means of a seven and one half (7-1/2) H.P. variable speed motor, and shall be controlled from a push button operating station with provisions for two speeds in either direction. The motor shall be connected to the platform by means of a suitable train of gearing. At maximum speed the platform shall make one complete revolution in forty-five seconds.
44. Section Locks:
Suitable means shall be provided for locking the three sections of the platform together for rotation, also locks to maintain alignment of the sections with elevator platform when it is desired to operate the elevators independently. The locking device shall be operated either by motors or electromagnets, and shall be controlled from the main operating station.
45. Operation Interlocks:
Operation Interlocks shall prevent the operation of the revolving mechanism unless the elevators are properly aligned and the interconnecting drive engaged. Additional interlocks shall prevent the operation of the elevators independently unless the sections of the revolving stage are in proper alignment and locked with their respective elevator platform.
46. Collector Rings:
On the underside of the revolving platform there shall be a suitable system of collector rings and brushes to feed the stage pockets located upon the platform. Eight collector rings are required.
The elevator platform shall be framed to receive a revolving platform, forty-three feet two inches (43'2") diameter, as indicated on the drawings. The platform shall be divided in three sections so indicated, and when not used as a turntable, it shall become an integral part of the elevator floor.
43. The platform shall be rotated by means of a seven and one half (7-1/2) H.P. variable speed motor, and shall be controlled from a push button operating station with provisions for two speeds in either direction. The motor shall be connected to the platform by means of a suitable train of gearing. At maximum speed the platform shall make one complete revolution in forty-five seconds.
44. Section Locks:
Suitable means shall be provided for locking the three sections of the platform together for rotation, also locks to maintain alignment of the sections with elevator platform when it is desired to operate the elevators independently. The locking device shall be operated either by motors or electromagnets, and shall be controlled from the main operating station.
45. Operation Interlocks:
Operation Interlocks shall prevent the operation of the revolving mechanism unless the elevators are properly aligned and the interconnecting drive engaged. Additional interlocks shall prevent the operation of the elevators independently unless the sections of the revolving stage are in proper alignment and locked with their respective elevator platform.
46. Collector Rings:
On the underside of the revolving platform there shall be a suitable system of collector rings and brushes to feed the stage pockets located upon the platform. Eight collector rings are required.
STAGE ELEVATORS, PIT FENCES
47. This Contractor shall furnish and install wire mesh railing guards around stage elevator pit between columns and to completely guard elevator openings at sub-basement level and also at basement level. This railing is to be three foot six inches (3'6") high, of one and one half (1-1/2") mesh - number ten (#10) wire. Sections of railing to be so arranged that they will raise easily by means of balance weights. Balance weight is to be enclosed in a metal box at each end of the rail unit sections, as shown on the drawings.
STAGE ELEVATORS, LIMIT SWITCHES
48. The elevator contractor shall furnish all material and perform all work indicated above, including the electric wiring between motors, controls, and limit switches with the exception of the wiring hereinbefore noted.
BAND CAR, MOTORIZED
49. This Contractor shall furnish and install an electrically operated band car, conforming appropriately to the shape and size of the orchestra pit. The car frame shall be substantially constructed of structural steel, and shall be of ample strength to support the entire orchestra. The top of the frame shall be covered with a wood floor.
50. The car shall be supported on wide-faced cast-iron wheels, carefully turned to prevent marring the stage floor. All wheels on the rear side of the car shell be keyed to a common driving axle, extending the full length of the car and mounted on roller bearing pillow blocks. The car shall be driven by a direct current motor, connected to the driving axle through a suitable train of gearing. Gearing shall, so far as possible, run in oil to insure quiet operation. Power for the operation of the gear shall be furnished by a storage battery, carried within the car frame. The battery shall consist of sixty (60) cells, Type MVA-7 Exide Ironclad as manufactured by the Electric Storage Battery Company.
51. Car Control:
The car shall be controlled by means of a compact reversing type manual controller, providing for three speeds in either direction. The controller shell be equipped with flexible cables, permitting mounting at any desired location on the car.
52. Battery Charger:
A fully automatic slate-mounted charging panel shall be furnished and installed In the location indicated. Panel shall be enclosed in a sheet metal case. The panel shall be designed to automatically charge the battery through a high-rate rectifier having a maximum capacity of six (6) amperes, and a low rate rectifier having a maximum capacity of one (1) ampere. Upon the completion of the charging circuit, the battery shall automatically receive current from the high rate rectifier and, when charge is completed, shall be disconnected from the high rate rectifier and connected to the low rate rectifier where it shall remain until the charging circuit is broken.
53. Included with the above equipment shall be a pair of charging leads with an approved charging plug.
50. The car shall be supported on wide-faced cast-iron wheels, carefully turned to prevent marring the stage floor. All wheels on the rear side of the car shell be keyed to a common driving axle, extending the full length of the car and mounted on roller bearing pillow blocks. The car shall be driven by a direct current motor, connected to the driving axle through a suitable train of gearing. Gearing shall, so far as possible, run in oil to insure quiet operation. Power for the operation of the gear shall be furnished by a storage battery, carried within the car frame. The battery shall consist of sixty (60) cells, Type MVA-7 Exide Ironclad as manufactured by the Electric Storage Battery Company.
51. Car Control:
The car shall be controlled by means of a compact reversing type manual controller, providing for three speeds in either direction. The controller shell be equipped with flexible cables, permitting mounting at any desired location on the car.
52. Battery Charger:
A fully automatic slate-mounted charging panel shall be furnished and installed In the location indicated. Panel shall be enclosed in a sheet metal case. The panel shall be designed to automatically charge the battery through a high-rate rectifier having a maximum capacity of six (6) amperes, and a low rate rectifier having a maximum capacity of one (1) ampere. Upon the completion of the charging circuit, the battery shall automatically receive current from the high rate rectifier and, when charge is completed, shall be disconnected from the high rate rectifier and connected to the low rate rectifier where it shall remain until the charging circuit is broken.
53. Included with the above equipment shall be a pair of charging leads with an approved charging plug.
ORGAN CONSOLE CARS, MOTORIZED
54. This Contractor shall furnish and install two (2) electrically driven cars, located one on each side of the auditorium as indicated, for moving the organ consoles from the rear of the alcoves to a position within view of the picture sheet. Each car shall consist of a structural steel frame and wood floor, of a size sufficient to accommodate the console and organist. Car shall be mounted on machined cast-iron wheels, keyed to driving axles which shall turn in roller bearing pillow blocks. A driving motor and a suitable train of silent reduction gearing, together with push buttons, control panel and limit switches shall be included. Push button shall be mounted as directed on the organ console. This contractor shall install tracks, flush with the floor for guiding the cars.
FOOTLIGHTS (MAIN), DISAPPEARING AND TILTING MECHANISM, MOTORIZED
55. This contractor shall furnish and install the complete mechanism for the automatic footlight shutters.
56. The mechanism shall consist of a series of frames for holding the footlights in the proper position, and arranged to be raised or lowered by means of a suitable system of linkages installed beneath the footlight trough. The same linkage system shall be used to lower the portion of floor directly back of the footlights to clear the path of the light. The floor section shall be mounted to a structural steel framework hinged to the stationary part of the stage floor. A rigid covering shall he provided over the footlight frames to form a continuous floor when the shutters ere closed.
57. Tilting Device:
An auxiliary mechanism shall be provided to tilt the footlights into a position which will illuminate the upper part of the stage when desired.
58. Each mechanism shall be actuated by means of an electric motor driving through a suitable system of quiet operating gearing. All shafting shall revolve in roller bearing pillow blocks.
59. Push button control shall be used, with the operating station mounted on the stage as directed. Automatic stops at the various operating positions shall be effected by means of geared limit switches.
56. The mechanism shall consist of a series of frames for holding the footlights in the proper position, and arranged to be raised or lowered by means of a suitable system of linkages installed beneath the footlight trough. The same linkage system shall be used to lower the portion of floor directly back of the footlights to clear the path of the light. The floor section shall be mounted to a structural steel framework hinged to the stationary part of the stage floor. A rigid covering shall he provided over the footlight frames to form a continuous floor when the shutters ere closed.
57. Tilting Device:
An auxiliary mechanism shall be provided to tilt the footlights into a position which will illuminate the upper part of the stage when desired.
58. Each mechanism shall be actuated by means of an electric motor driving through a suitable system of quiet operating gearing. All shafting shall revolve in roller bearing pillow blocks.
59. Push button control shall be used, with the operating station mounted on the stage as directed. Automatic stops at the various operating positions shall be effected by means of geared limit switches.
AIR EFFECT LINE
60. This Contractor shall furnish and install in trough in stage floor adjoining the footlights an air line with nozzles, approximately three (3") inches on center. This pipe shall be in three (3) sections with control valves so arranged that each section can be operated independently or all sections can be operated together.
61. This Contractor shall also provide two (2) outlets on each side of the stage, a total of four (4). This Contractor shall provide the necessary stage floor pockets for covering the air control valves. The floor pockets shall be set in place by others. This Contractor shall furnish and install two (2) outlets in the machine room and one (l) outlet in the main control room for cleaning. This Contractor shall furnish and install all necessary piping to connect all the above outlets and effect pipes to the auxiliary air receiver located as specified elsewhere in these specifications. The trough, the wood strip covering and all other woodwork on the stage shall be by OTHERS.
61. This Contractor shall also provide two (2) outlets on each side of the stage, a total of four (4). This Contractor shall provide the necessary stage floor pockets for covering the air control valves. The floor pockets shall be set in place by others. This Contractor shall furnish and install two (2) outlets in the machine room and one (l) outlet in the main control room for cleaning. This Contractor shall furnish and install all necessary piping to connect all the above outlets and effect pipes to the auxiliary air receiver located as specified elsewhere in these specifications. The trough, the wood strip covering and all other woodwork on the stage shall be by OTHERS.
FOOTLIGHTS (CYC), TROUGH COVERS, MOTORZIED
62. This Contractor shall furnish and install tho complete mechanism for opening and closing the covers over the cyclorama light trough.
63. The covers shall be operated in three separate groups, as indicated. For each group there shall be provided an electric motor, and a suitable train of quiet reduction gearing, driving a line shaft, supported on roller bearing pillow blocks. To the line shaft there shall be attached cast steel arms, the ends of which shall be attached to the covers by means of sliding connections. The arms shall be counterweighted to balance the weight of the covers.
64. The motion of the covers shall be controlled from a push-button operating station, installed on the stage as directed, and automatic stops shall be effected by means of geared limit switches. This Contractor shall furnish and install all machinery, motors and control apparatus.
63. The covers shall be operated in three separate groups, as indicated. For each group there shall be provided an electric motor, and a suitable train of quiet reduction gearing, driving a line shaft, supported on roller bearing pillow blocks. To the line shaft there shall be attached cast steel arms, the ends of which shall be attached to the covers by means of sliding connections. The arms shall be counterweighted to balance the weight of the covers.
64. The motion of the covers shall be controlled from a push-button operating station, installed on the stage as directed, and automatic stops shall be effected by means of geared limit switches. This Contractor shall furnish and install all machinery, motors and control apparatus.
FIRE CURTAIN (MAIN), GENERAL
65. General Requirements:
The proscenium opening between auditorium and stage shall have a curtain made of incombustible materials constructed and installed to lap the masonry opening not less than eighteen (18") inches on each side and two feet (2'-0") at the top and to intercept flame and smoke and prevent glow from a severe fire on the stage from showing on the auditorium side for a sufficient length of time to permit the safe exit of all persons from the theatre. The period of protection shall not be less than fifteen (15) minutes. The emergency closing of the curtain in case of fire shall be effected by gravity.
66. General Design of Frame:
This curtain shall be made in two (2) sections (upper and lower) and each section shall have a rigid frame of steel covered with asbestos cloth on both auditorium and stage sides.
67. General Design of Frame: (Continued)
The curtain shall have in no case a thickness of less than ten (10") inches nor less than one-one hundred-twentieth (1/120)of the width of the proscenium opening. The framework shall be of rolled shapes and shall have interior members of structural shapes, tubes, bars or rods of steel. The top of the lower frame shall extend not less than two (2'-0") feet above the bottom of the upper frame when the curtain is at its lowest or closed position. The horizontal members shall be spaced not more than eight (8'-0")feet apart and the vertical members not more than ten (l0'-0") feet apart. The bottom of the lower section of the curtain shall have a yielding pad of incombustible material not less than eight (8") inches thick covered with a double thickness of the same asbestos cloth as used on the face of the curtain. On the top of the upper section extending across its full width, there shall be a continuous smoke seal of an inverted channel the outer edge of which shall dip into a three (3") inch by three (3") sand box made of number sixteen (#16) iron and mounted on a recess on the proscenium wall.
68. Covering:
Both the auditorium and stage side of the framework shall be covered with a brass wire re-reinforced close-woven asbestos cloth. The cloth shall have a content of eighty-five (85) percent asbestos and shall weigh 3.42 lbs. per square yard. All strips of cloth shall be in one continuous length of the full height of the curtain. That stripe of cloth shall be lapped not less than one (l") inch and sewed with two (2) lines of stitching of asbestos thread, which shall be of the same or greater strength than the yarns of the cloth. The asbestos cloth covering shall be secured by a clamping strip of one and one- quarter inch by five-sixteenths inch (1-1/4" x 5/16") half oval iron, bolted six (6") inches on centers on all sides to the outside members of the frame.
69. The bottom of the upper section shall be covered with only a double thickness of the same asbestos cloth as used on the face of the curtain without any pad.
70. Smoke Pocket and Guides:
The sides of the curtain shall run in and be guided throughout its travel by smoke pockets and rigid steel guides. The smoke pockets shall extend from the stage floor to a height of not less than one hundred and two feet and nine inches (102'9"). The smoke pocket shall be made of not less than twenty-eight by one-half inch (28" x 1/2") plate; on the wall edge there shall be a four inch by four inch by three-eighths inch (4" x 4" x 3/8") angle and on the outer edge two and one-half by tow and one-half by three eights (2-1/2" x 2-1/2" by 3/8") angle attached to which shall be and eighteen by three-eighths inch (18" x 3/8") plate. The guide shall be built integral with the smoke pocket and shall be not less than three inch by three inch by three-eights inch (3" x 3" x 3/8") angle. The guide for the lower section shall be continuous for the full height of the smoke pocket. The guide for the upper section shall extend from the top of the smoke pocket and continue down as far as the bottom member of the upper section when this section is in closed position.
71. At this point, there shall be a heavy seat angle on which the lower member of the upper section shall rest when at its closed position. On the eighteen inch by three-eights inch (18" x 3/8") plate, there shall be a one and one-half (1-1/2") inch smoke stop. This stop angle shall extend from stage floor to a height four (4'0") feet higher than the proscenium arch. The smoke pockets shall be securely bolted in place every four (4'0") feet to wall anchors.
The proscenium opening between auditorium and stage shall have a curtain made of incombustible materials constructed and installed to lap the masonry opening not less than eighteen (18") inches on each side and two feet (2'-0") at the top and to intercept flame and smoke and prevent glow from a severe fire on the stage from showing on the auditorium side for a sufficient length of time to permit the safe exit of all persons from the theatre. The period of protection shall not be less than fifteen (15) minutes. The emergency closing of the curtain in case of fire shall be effected by gravity.
66. General Design of Frame:
This curtain shall be made in two (2) sections (upper and lower) and each section shall have a rigid frame of steel covered with asbestos cloth on both auditorium and stage sides.
67. General Design of Frame: (Continued)
68. Covering:
Both the auditorium and stage side of the framework shall be covered with a brass wire re-reinforced close-woven asbestos cloth. The cloth shall have a content of eighty-five (85) percent asbestos and shall weigh 3.42 lbs. per square yard. All strips of cloth shall be in one continuous length of the full height of the curtain. That stripe of cloth shall be lapped not less than one (l") inch and sewed with two (2) lines of stitching of asbestos thread, which shall be of the same or greater strength than the yarns of the cloth. The asbestos cloth covering shall be secured by a clamping strip of one and one- quarter inch by five-sixteenths inch (1-1/4" x 5/16") half oval iron, bolted six (6") inches on centers on all sides to the outside members of the frame.
69. The bottom of the upper section shall be covered with only a double thickness of the same asbestos cloth as used on the face of the curtain without any pad.
70. Smoke Pocket and Guides:
The sides of the curtain shall run in and be guided throughout its travel by smoke pockets and rigid steel guides. The smoke pockets shall extend from the stage floor to a height of not less than one hundred and two feet and nine inches (102'9"). The smoke pocket shall be made of not less than twenty-eight by one-half inch (28" x 1/2") plate; on the wall edge there shall be a four inch by four inch by three-eighths inch (4" x 4" x 3/8") angle and on the outer edge two and one-half by tow and one-half by three eights (2-1/2" x 2-1/2" by 3/8") angle attached to which shall be and eighteen by three-eighths inch (18" x 3/8") plate. The guide shall be built integral with the smoke pocket and shall be not less than three inch by three inch by three-eights inch (3" x 3" x 3/8") angle. The guide for the lower section shall be continuous for the full height of the smoke pocket. The guide for the upper section shall extend from the top of the smoke pocket and continue down as far as the bottom member of the upper section when this section is in closed position.
71. At this point, there shall be a heavy seat angle on which the lower member of the upper section shall rest when at its closed position. On the eighteen inch by three-eights inch (18" x 3/8") plate, there shall be a one and one-half (1-1/2") inch smoke stop. This stop angle shall extend from stage floor to a height four (4'0") feet higher than the proscenium arch. The smoke pockets shall be securely bolted in place every four (4'0") feet to wall anchors.
FIRE CURTAIN (MAIN), RIGGING, MOTORIZED
72. Lifting Cables
and Rigging:
Both the upper and
lower frames shall be hung on twelve (12) steel lifting cables, one at each end
and one at intermediate points not over ten (10’) feet apart. These cables shall be not less than one-half
(1/2”) inch diameter and shall be attached to the curtain with three-quarter
(3/4”) inch turnbuckles and to the top of the counterweights with eyebolts and
coil springs. The counterweight frames
shall be made of not less than six (6”) inch thick top and bottom weights
connected by two (2) rods spaced to receive the intermediate
counterweights.
73. The counterweight frames shall operate on two
and one-half inch by two and one-half inch by three-eight inch (2-1/2” x 2-1/2”
x 3/8”) tee bar tracks, which shall have spacing U brackets of two and one-half
by three-eight inch (2-1/2” x 3/8”) iron every four (4’) feet and shall be
double bolted to the wall. The
counterweight tracks shall set on the stage floor and continue for the full
travel of the counterweight frame plus five (5’) feet. The tracks at the stage floor shall be
enclosed to a height of eight (8’0”) feet by a guard made of number sixteen
(#16) sheet iron.
74. For each cable, there shall be a heavy pattern
twenty (20") inch diameter machine turned curtain block. Each counterweight shall have a heavy pattern
twenty-four (24") inch head block with separate machine turned grooves for
each cable. All blocks shall be
securely keyed to solid shafts. The
shafts run in two (2) double roller bearing pillow blocks. The pillow blocks shall be supported on two
(2) ten (10") inch channels set parallel to the proscenium wall. These channels shall extend across the full
width of the stage and shall rest on and be securely bolted to the steel of the
building. Between the upper and lower sections of the curtain there shall be a
system of cables and sheaves so arranged that the two (2) sections of the
curtain shall move simultaneously - both sections starting and stopping at the
same time. This system of cables and
sheaves shall be of the same size as specified for the lifting cables.
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