The maintenance requirements of express elevators for passenger elevator brakes:
1. The brake must ensure the braking force and strengthen the maintenance and inspection of the brake spring. During the inspection, first close the brake shoe in the locked state, and then use the brake shoe release device to open the brake shoe. You can first detect whether the spring has become Soft, you can also knock the spring with a hand hammer, and judge whether the spring has cracks and failure by the sound.
2. The opening and closing of the brake should be reliable within the effective stroke, all components should operate normally without jamming, all spliced ​​parts should be lubricated and maintained once a week, and L-AN16 total loss system oil should be dripped into the movable parts, and Note that the oil should not be contaminated on the surface of the brake wheel and brake band.
3. Check whether the brake shoe is attached to the surface of the brake wheel, whether the brake band at both ends of the brake shoe is detached from the body of the brake shoe; whether the surface quality of the brake wheel is good, and the rivets for fixing the brake band are not allowed to contact the brake wheel Contact, the brake band should be replaced when the wear exceeds 1/3 of the thickness of the brake band; the adjustment nut and lock nut of the brake must be checked for looseness.
4. The action of the brake should be flexible and reliable. The working surface of the brake shoe and the brake wheel should be clean, and the two should fit closely. The contact surface between the newly installed brake band and the brake wheel shall not be less than 80% of the area of ​​the brake band, which can be measured by the circle method (namely called the encircling measurement method or the eight-point measurement method). When the brake is released, the brake shoe should leave the brake wheel at the same time, and the brake release gap should not be greater than 0.7mm, without local friction. During emergency braking, the sliding distance of the elevator should not exceed 100mm calculated at a running speed of 0.5m/s.
5. There should be no looseness in the brake coil contacts, and the outside of the coil must be well insulated to prevent short circuits. When the DC electromagnetic brake is released, the normally closed contact of the contactor is disconnected and the resistance is inserted into the coil loop to reduce the temperature rise. During normal starting, the voltage across the coil is 110v, the resistance in series is 55±5Ω, the temperature rise of the brake coil should not exceed 60 degrees Celsius, and the absolute temperature should not exceed 80 degrees Celsius.
6. The pin of the brake can move freely, without dust or grease, and can be lubricated with thin oil. When the pin wear exceeds 5% of the original diameter or the ellipticity exceeds 0.5mm, a new shaft should be replaced. . The lever system and spring should be replaced in time if cracks are found.
7. The movable iron core of the electromagnet should slide flexibly in the copper sleeve. If necessary, it can be lubricated with graphite powder (the pencil lead can be ground into powder can be substituted).
8. The brake belt should be free of greasy or paint to prevent excessive braking slippage and reduce braking torque. It can be scraped lightly with a small tool or cleaned with kerosene.
9. The rivets for fixing the brake band should be buried in the countersunk head seat hole. The rivet head of the new brake band sinks to a depth of not less than 3mm. The rivet head of the brake band should not contact the brake wheel at any time.
10. In order to ensure the uniform clearance between the upper and lower ends of the brake shoe and the brake wheel and the uniform force applied on the entire contact surface, the brake base must be adjusted with a shim so that the brake shoe is consistent with the center horizontal line of the brake wheel and reaches The center height and straightness requirements, therefore, pay attention to whether the gasket is displaced.
11. The surface of the brake wheel should be free of scratches and high-temperature coking particles, if any, it should be polished smoothly.