Iowa Admin. Code r. 875-73.16

Current through Register Vol. 47, No. 5, September 4, 2024

Rule 875-73.16 - Existing hydraulic elevators

(1) Cylinders of hydraulic-elevator machines shall be provided with a means for releasing air or other gas.

(2) Each pump or group of pumps shall be equipped with a relief valve conforming to the following requirements:

a.Type and location. The relief valve shall be located between the pump and the check valve and shall be of such a type and so installed in the bypass connection that the valve cannot be shut off from the hydraulic system.

b.Setting. The relief valve shall be preset to open at a pressure not greater than that necessary to maintain 125 percent of working pressure.

c.Size. The size of the relief valve and bypass shall be sufficient to pass the maximum rated capacity of the pump without raising the pressure more than 20 percent above that at which the valve opens. Two or more relief valves may be used to obtain the required capacity.

d.Sealing. Relief valves having exposed pressure adjustments, if used, shall have their means of adjustment sealed after being set to the correct pressure.

Exception: No relief valve is required for centrifugal pumps driven by induction motors, provided the shut-off, or maximum pressure which the pump can develop, is not greater than 135 percent of the working pressure at the pump.

(3) Storage and discharge tanks shall be covered and suitably vented to the atmosphere.

(4) Hydraulic elevators shall be governed by the rules contained in Chapter 73 that apply to electric elevators except the following rules which are exempt: 73.5, 73.6(3), 73.7(2), 73.7(4), 73.7(7),73.9(9), 73.10(3), 73.11, 73.13, and 73.14.

(5) Rescinded lAB 3/7/01, effective 4/11/01.

Iowa Admin. Code r. 875-73.16