Pennsylvania Code › Title 34 - LABOR AND INDUSTRY › Part I - Department of Labor and Industry › Chapter 7 - ELEVATORS, LIFTS, ESCALATORS, DUMBWAITERS, HOISTS ANDTRAMWAYS › Subchapter B - PASSENGER ELEVATORS › SPECIAL REQUIREMENTS › Section 7.76 - Hydraulic passenger elevators

Current through Register Vol. 54, No. 28, July 13, 2024
(a)
					 The valve chambers and cylinders of all hydraulic passenger elevators shall be
					 equipped with means for removing any accumulation of air.
(b) New hydraulic and oil-electric elevators
					 shall be equipped with supply and discharge pipes of sufficient area as to be
					 unaffected by the operation of any other elevator on the same system. Supply
					 tanks shall be of sufficient capacity to provide for an adequate liquid reserve
					 to prevent the entrance of air or other gas into the system and to permit a
					 travel of at least three feet beyond the upper terminal landing. Such
					 permissible minimum liquid level shall be clearly indicated.
(c) In new installations, structural steel
					 guides shall be provided for every crosshead having a travel in excess of 15
					 feet; structural steel hangers shall be provided for traveling sheaves when the
					 travel of the sheaves exceeds l5 feet. In existing installations, structural
					 steel guides shall be provided for every crosshead when necessary to prevent
					 swaying of the crosshead.
(d) Each
					 pump shall be equipped with an automatic bypass. Each pump connected to
					 pressure tanks of hydraulic passenger elevators shall be equipped with one or
					 more water relief valves, which shall be of ample capacity to prevent a
					 pressure in excess of the maximum allowable pressure of the pump or tank. There
					 shall be no shutoff valve between the water relief valve and the pump or tank
					 which it protects. The discharge from the water relief valves shall be
					 conducted to the discharge tank or to the pump suction.
(e) Pressure tanks of hydraulic passenger
					 elevators shall be equipped with a water relief valve of sufficient capacity to
					 discharge the pump delivery without an increase of more than l5 pounds above
					 the allowable working pressure of the tank. If, in the judgment of the
					 Department, the water relief valve on the pump will provide sufficient
					 protection, the water relief valve for the pressure tank may be
					 omitted.
(f) In new installations,
					 the car platform of a direct plunger passenger elevator shall be securely
					 fastened to the head of the plunger by not less than four 5/8 inch diameter
					 bolts or by any other means whereby a factor of safety of four shall be
					 maintained provided such alternate means be submitted to the Industrial Board
					 for approval. When the plunger consists of more than three sections and the
					 elevator car is equipped with counterweights, the car platform shall be further
					 secured to the bottom section of the plunger by a noncorrosive cable inside of
					 such plunger.
(g) When a new
					 elevator car is equipped with counterweights the plunger head shall be
					 constructed of steel or wrought iron material.
(h) The plunger of every uncounterweighted
					 hydraulic elevator having a travel in excess of 75 feet shall be equipped with
					 a traveling guide or follower which will remain midway between the car and the
					 stuffing box throughout the entire length of travel.
(i) All pressure tanks for hydraulic
					 passenger elevators and pipe materials other than threaded heavy-duty metal
					 pipe shall first be approved by the Board.
(j) Each hydraulic passenger elevator shall
					 be provided with automatic limit stops arranged to bring the car to a gradual
					 stop at terminal landings independent of the car-controlling mechanism. For
					 plunger elevators having a car speed of 100 or less feet per minute, the
					 automatic limit stop may be an independent cable with button stops on the car,
					 such cable to be connected to the main operating valve. For horizontal or
					 vertical cylinder machines having a car speed of 100 or less feet per minute
					 the automatic limit stop may be an independent cable actuated by the traveling
					 crosshead and connected to the main operating valve. Each hydraulic passenger
					 elevator having a car speed more than 100 feet per minute shall be provided
					 with independent automatic stop valves.
(k) The capacity of operating and stop valves
					 shall not be more than will permit the operation of the car with the maximum
					 load at the allowable rate of speed.
(l) Piston rods shall be thoroughly examined
					 by an approved inspector at least once every three years.
(m) Cylinder or plunger passenger elevators
					 in which the motive power is steam, gas, or air shall, when possible, come
					 within the requirements for hydraulic passenger elevators.
(n) Existing installations of every type of
					 hydraulic elevator shall be changed to meet the requirements for new
					 installations, when necessary for safe operation, if ordered by the
					 Department.
(o) Electrically
					 controlled hydraulic and oil electric elevators shall be equipped with two
					 magnetic switches both of which shall be closed to complete the motor circuit
					 unless there is a second control means (for example, a valve) in which case
					 only one such magnetic switch is required in the motor control
					 circuit.
(p) Each hydraulic
					 passenger or freight elevator shall be equipped with an approved
					 electrically-controlled normally closed valve, operating devices and control
					 equipment, including anti-creep leveling devices, and terminal stopping
					 devices.
(q) When
					 electrically-operated valves are installed to replace existing
					 mechanically-operated valves, for rated speeds of more than 100 feet per
					 minute, existing terminal stopping devices, consisting of an automatic stop
					 valve independent of the electric control valve and operated by the movement of
					 the car as it approaches the terminals, where provided, shall be
					 retained.
(r) Anti-creep leveling
					 devices shall maintain the car within three inches of the landing from any
					 point within the interlock zone irrespective of the position of the hoistway
					 door. For electric hydraulic elevators, it is required to operate the car only
					 in the "up" direction. For maintained-pressure hydraulic elevators, it is
					 required to operate the car in both directions, and shall operate in
					 conjunction with an approved electrically-controlled, valve-operating system.
					 The closing of this control device shall not be dependent on the completion or
					 maintenance of an electric circuit for the interruption of the power. However,
					 movement of the car in response to the anti-creep leveling device shall be
					 prevented by the operation of either the stop switches in the pit or on the car
					 top or by the electric contacts provided for top or side emergency exits. This
					 exception shall apply to all installations for which a permit has been issued
					 subsequent to the effective date of this exception.
(s) Prior to the approval of the electrical
					 control valve and related parts for water hydraulic elevators, the manufacturer
					 of each control valve to be approved shall submit the following to the Board:
(1) Two complete sets of assembly and detail
					 drawings of the control valve and related parts.
(2) All drawings shall be to scale.
(3) All pertinent information as to materials
					 and clearances.