Custom Search
|
|
|
||
CHAPTER 3
HYDRAULIC ELEVATORS
3.1 INTRODUCTION
NOTE: Paragraphs identified with a vertical line in the left margin are inspections that should
be made by certified Vertical Transportation Equipment Inspectors only.
3.1.1 Scope
The inspection procedure for hydraulic elevators included in this chapter is not only an
inspection of all safety related functions, but is also an inspection to determine the condition of
the equipment and identify areas that need improvement. Proper maintenance is needed to keep
the elevator operating. When preventive maintenance is lacking, shut downs will occur. Part II
of the ANSI/ASME A17.2 Inspector's Manual for Elevators and Escalators addresses the safety
aspect of the inspection of hydraulic elevators. In this chapter we will identify the specific
Division of Part II which relates directly to the inspection procedure being followed in this
text. It is intended that each noted division should be reviewed as it is identified and suggested
procedures followed. The maintenance and performance considerations of the inspection will be
addressed in the following test. See Figures 3-1 and 3-2, which show various elevator
arrangements with component names that will be used in this chapter.
3.1.2 Performance Criteria
As was stated, the purpose of procedures as outlined in Section 2.1.2 are applicable.
3.1.2.1 Elevator Speed (Hydraulic Elevators). Elevator operating speed is measured with a
tachometer while the elevator makes a full run through the hoistway with no load in the car.
With hydraulic elevators, it is necessary to make this reading from the top of the car by holding
the tachometer on the guide rail. The up direction operating speed should be maintained at a
level of plus or minus 5% of the rated speed (to be found on the cross head of the car) under any
load condition. The down speed is much more difficult to obtain because the speed is directly
related to the weight in the car. Usual adjustments are made such that contract speed is obtained
in the down direction with 50% load on the car. The empty car down speed should be
maintainable at about 10% below contract speed and full load down speed should be
maintainable at about 10% above contract speed.
3-1
|
||