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 14.2.2 Landing Guards And Skirts
On the ascending sides of a levellator, the scissors or jaws should be guarded by permanent
solid walls, wire mesh partitions or solid steel panels. Sectional telescoping type metal safety
skirting is to be installed to completely cover any exposed portions of the lift equipment and to
act as toe guards for a descending levellator platform.
14.2.3 Illumination
The levellator platform and loading areas should be illuminated at all times when it is in
operation. An intensity of not less than one foot-candle should be maintained at all points.
14.2.4 Power Unit
14.2.4.1 Main Line Switch. The inspector should closely examine the condition of the main line
switch before inspecting any moving part because opening the switch may not have removed all
power from a particular levellator. This condition is very prevalent when levellators share the
same pump unit.
14.2.4.2 Pumps. Pumps can be of the direct-connected type or driven by multiple V-belts.
14.2.4.3 Assembly. A standard levellator power unit consists of a hydraulic oil reservoir, a
pump unit, an electric motor for driving the pump, and a manual lowering valve in case of power
failure. (See Figure 14-3).
14.2.4.4 Pumps. Pumps should be checked for leakage around the shaft, and for unusual noise
that could be caused by cavitation due to a partially plugged suction line or strainer.
14.2.4.5 Drives (if applicable). Belt drives should be checked for wear, initial tension, and
reasonable equality of tension among members of a set. Chain drives should be checked for
wear, both on the chain and sprockets. Direct-drive couplings, where accessible, should be
checked for excessive play.
14.2.4.6 Relief and Check Valves. Determine whether relief and check valves are provided and
properly located. Examine relief valves, where provided, and note their condition and whether
there is leakage. Relief valves should have a lead block and wire type seal on the means of
adjustment and be intact. Determine whether the check valve operates to stop and hold the lift
when the pump stops.
14-5
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