Construction scheme for replacing steel wire rope of elevator

All personnel (5-6 persons) engaged in this work must hold the elevator maintenance certificate issued by the Quality Supervision Bureau, and work with the certificate, and a person with a certain professional and technical level shall be responsible for unified command.

Hang warning signs such as "no use for elevator repair" in front of the hall doors of the repaired elevators and "no switching on by someone" on the main power switch of the elevator in the machine room. Use yellow signs on the hall doors of the first floor and the top floor to enclose the work site and hang a tag: "no irrelevant personnel are allowed to enter the dangerous area".

The personnel engaged in the work shall wear relevant personal safety protection articles, such as insulating shoes, hard hats, safety belts, etc., and check the safety and reliability of the protection articles.

Prepare sufficient repair tools (estimated as per one elevator) and relevant equipment, as follows:

a wire rope: φ One 8mm and 220m long, and two 1.5m long straps (for lifting the car).

Steel wire: φ 8mm and 50m long.

Spring scale: weighing range: 0-25kg.

Two interphones.

Several insulating tapes.

Nylon pull rope 200m.

10 wire rope clamps.

Steel pipe supporting counterweight: φ 0～ φ 50mm, 2 pieces with a length of 1.5-1.8m (should be able to bear more than 3 tons).

Chain block: one with a load of 1.5-3 tons.

The above tools shall be comprehensively and carefully inspected before construction, and can only be used after the quality and safety are confirmed to be up to standard.

Main technology and safety process of wire rope replacement

The personnel shall be divided into three groups, with at least two people in each group. They shall take the intercom. One group of the machine room will open the elevator car to the top floor, cut off the power supply after leveling, and notify the other group to enter the shaft bottom.

The pit group shall first cut off the "emergency stop" switch at the bottom of the shaft, and measure the distance between the impact plate of the counterweight lower beam and the buffer for the reference of the length of the shear switch rope. Place one end of the counterweight and the bearing steel pipe on the ground, align the other end with the lower beam of the counterweight, turn on the "emergency stop" switch at the bottom of the shaft, and use the walkie talkie to inform the personnel of the machine room to move the elevator slowly upward until the counterweight frame completely presses the steel pipe, so that the elevator cannot move slowly upward.

The machine room group cuts off the main power supply and hangs a notice board, then lifts the car with a chain block and a steel wire rope (the steel wire rope shall pass through the lifting ring on the roof of the machine room, and note that the lifting ring mouth shall be padded with some materials to increase the contact surface), and uses a chain block to make the speed governor act manually (cause the car safety gear to act, and then lower the hoisted car a little to make the safety gear wedge firmly on the guide rail).

After item 1 is completed correctly, first remove 1 / 2 of the elevator traction rope, place it on a flat ground, and remove the rope head cone sleeve. According to the length of the steel wire rope and the measured distance between the counterweight lower beam and the buffer. When cutting the new special steel wire rope for elevator, attention shall be paid to: the newly purchased steel wire rope shall be carefully checked to see whether there is a product certificate (BR), whether the diameter is the same as the original, and whether the elevator professional type (8 × 19, the outer strand is thick and the inner strand is thin); Whether it complies with the national standards. During the process of cutting and measuring the rope length, excessive friction on the ground shall not be allowed to prevent damage.

Put the new rope into the cone sleeve, and then tie it tightly with fine iron wire rope at 200mm. After bending each strand of steel wire into the required shape, pull the steel wire rope into the cone sleeve with force. The steel wire rope should be slightly lower than the cone sleeve.

Wrap it on the cone sleeve mouth with adhesive tape, and fasten it with the rope buckle.

Assemble 1 / 2 of the new traction wire rope as per the original position, and then dismantle the other 1 / 2 of the old traction wire rope as per items 3 and 4 above, and then assemble it as per the original position. Then, use the chain block to lift the lift car by about 80mm, restore the speed governor and safety gear to the normal position, and then pull the chain block to lower the lift car to make the steel wire fully stressed. At this time, the rope head bolts on the car and counterweight side shall be corrected to make the difference between the tension of each traction rope and its average tension ≤ 5% (the tension shall be detected by a spring scale).

Test run

After the above contents are qualified, make the elevator slowly jog down about 0.5mm, inform the personnel of the pit team to enter the shaft bottom and take out the two steel pipes of the top counterweight, so that the steel wire rope is fully stressed. At this time, further adjust the tension of the traction rope, and enter the car roof to carefully check whether the arrangement position of the replaced traction rope is correct. After it is correct, the elevator can be operated at a slow speed throughout the whole process, and then transferred to a fast speed for trial operation.

experiment

1. Elevator static load test: passenger elevators, medical elevators and freight elevators under 2 tons bear 200% of the rated load, and other types of elevators bear 150% of the rated load. When the load is stopped, the load-bearing components shall be free from damage and the traction steel rope shall be free from sliding displacement after being loaded with the specified load for 10 minutes. (use people as heavy objects on site)

2. Traction capacity test

Under the following conditions equivalent to the most serious braking of the elevator, stop for several times for traction inspection, and the car shall be able to stop completely during each inspection.

The lift car is loaded with 125% rated load and descends to the lower range of travel at rated speed.

The lift car goes up to the upper range of travel at the rated speed without load.

The project can be put into normal operation after passing the test according to the above provisions.