Annual Safety Test with Oily Guide Rails
During an annual Category 1 test on a six-stop geared traction elevator rated 3,000 lb at 350 fpm, the governor trips at 455 fpm and the car safety sets. The car slides several feet before stopping, leaving heavy skid marks on both rails. The rails feel oily. Building maintenance says they lubricate the rails monthly to stop squeaks. The governor rope was replaced last year and the governor seal is intact. The mechanic measured governor trip speed with a calibrated tachometer and confirmed the reading. The car safety linkage moves freely by hand, and the safety jaws show no obvious wear. The building is a busy medical office and the owner wants the elevator back in service before the afternoon clinic.
1. Is the governor trip speed acceptable? Explain your reasoning.
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The measured trip speed is 455 fpm on a 350 fpm elevator, which is 130% of rated speed. For this type of car safety governor, the code generally requires tripping at not less than 115% and not more than 140% of rated speed, so 130% is within the permitted band. The mechanic should still confirm that the tachometer is calibrated, that the governor is the correct one for the car speed, and that the reading was taken at the governor rather than estimated from car speed. The governor rope replacement and seal condition are relevant because a slipping governor rope can give a false trip reading. However, the governor speed is not the reason to fail this test. The failure is the distance the car slid after the safety set, which points to the safety/guide-rail interface, not the governor trip point.
2. Why did the car safety slide, and what must be done before retesting?
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A sliding car safety depends on friction between the safety jaws and the guide rails to stop the car. Oil on the rails reduces that friction and can let the car slide even though the governor tripped and the linkage moved. The mechanic should take the elevator out of service, clean both guide rails with an approved cleaner, and inspect the rail surfaces for oil, grease, paint, or other contamination. The safety jaws, wedges, rollers, springs, and linkage should be checked against the manufacturer's dimensions and instructions. The governor rope should be checked for tension and grip, since a slipping governor rope can prevent full safety application. After cleaning and any needed adjustment, the safety test must be repeated per the adopted code with the required load. The elevator should not be returned to service merely because the rails were wiped; the retest must demonstrate that the safety stops the car within the code distance.
3. What should the mechanic report, and what operating status should the elevator have?
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The mechanic should fail the Category 1 test, document the governor trip speed, the slide distance, the oily rail condition, and the building's lubrication practice, and place the elevator out of service until repairs and a successful retest are completed. The report should state that rail lubrication is not permitted unless the safety manufacturer specifically allows it, and that the building maintenance crew must stop applying oil. The owner should receive a written notice explaining that the elevator cannot be returned to service for the afternoon clinic. The mechanic should notify the AHJ as required and should not issue a passing certificate. If the safety still slides after cleaning and correct adjustment, the safety or guide rails may need repair or replacement, and the elevator must remain out of service until the cause is corrected and the test is passed.