Tengdong mine is mined by deep shaft (mining level - 865m), and jkmd-3.5 is used for auxiliary shaft × 4 (Ⅲ) e - (TD) multi rope friction hoist (parameters: friction wheel diameter: 3500mm; head sheave wheel diameter: 3500mm; wire rope diameter / Number: 38mm / 4; wire rope spacing: 300mm; lifting speed: 8.8m/s). During the operation of multi rope friction hoist, due to the action of internal or external factors, the four lifting steel ropes are prone to different degrees of movement along the lifting direction. When the amount of movement of a rope is too large, the rope will be loose and swing greatly, which will affect the safe operation of the lifting equipment. Combined with the actual situation of the auxiliary shaft hoist in Tengdong mine and the relevant problems on site, this paper expounds the causes of the movement of the hoisting steel wire rope and the relevant solutions.

1. Causes of movement

1.1 internal causes of movement of lifting head rope

(1) The length of the four lifting wire ropes is not exactly the same during replacement. Affected by the process of rope replacement (single rope is replaced one by one) and the allowance of Rope adjustment oil cylinder, the length of four new ropes cannot be completely guaranteed when replacing the auxiliary shaft hoisting rope, so it may cause the hoisting rope with rope length to move during operation.

2. The extension performance of the four lifting wire ropes is not exactly the same. Affected by the process and materials of steel wire rope prepared by the steel wire rope manufacturer, the extensibility of the four steel wire ropes will not be exactly the same, and the lifting rope with strong extensibility is easy to move.
3. Other reasons. For example, the installation process causes large changes in the elongation of the steel wire rope during use, and the stress of the steel wire rope caused by the defect of the connecting device is uneven.

1.2 external causes of the movement of the lifting head rope

1. The groove depth of the four lifting steel wire ropes is not exactly the same and the thickness of friction increasing grease on the steel wire ropes is uneven. The above conditions will lead to different winding radius of the lifting ropes. After relevant data statistics and scientific verification, the larger the lifting height of the mine is, the easier it is to cause the movement of the lifting ropes.
2. The oil gun positions of the four steel wire rope adjusting oil cylinder are not exactly the same, resulting in the movement of the lifting head rope.
3. The oil gun of the oil cylinder of a steel wire rope has no allowance, and a single rope is no longer stressed. When the oil gun of the oil cylinder is in different positions, even the oil cylinder of individual lifting rope has no allowance, resulting in no adjusted allowance of the corresponding lifting rope, which is very easy to cause the movement of the lifting rope.
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5. Appearance of movement

(1) The hoisting wire rope can be seen to swing significantly at the wellhead.

(2) The lifting wire rope has obvious up and down swing at the rope outlet of the garage.

(3) The steel wire rope is out of groove from the sheave or drum rope groove.

(4) The steel wire rope in the shaft is not vertical and is obviously not stressed.

The above four abnormal phenomena are more prominent, and the maintenance personnel can directly find the problems through visual inspection.

3. Adjustment method in case of movement

According to the problems existing in Tengdong mine, the technical department of our company put forward the solution: use the "five-way valve" specially regulating the oil cylinder, that is, one oil inlet pipe is connected with four oil outlet pipes, and one oil outlet pipe is added at the pipe head respectively Φ For a 10mm ball valve, a 500mm high-pressure oil pipe is added behind the ball valve of the oil outlet pipe. The high-pressure oil pipe is connected with the four rope regulating cylinders. The four ropes are pressurized at the same time by using the structure connected with the four oil outlet pipes, which can adjust the pressure of the four cylinders at the same time, so as to ensure the balanced stress of the steel wire rope and the safe lifting of the auxiliary shaft. Similarly, the use of "five way valve" combined with tank pressure, auxiliary shaft lifting rope and rope cutting have good results.

4. Existing shortcomings and innovation direction in the next step

The "five-way valve" can better complete the adjustment of rope displacement, tank position pressure suppression and rope cutting, but there are still deficiencies to be improved in the actual use process: for example, before a rope cutting in the auxiliary shaft, the basic allowance of the oil cylinder on the large tank side of the auxiliary shaft is about 200mm. Two days before the rope cutting, the signal driver at the upper wellhead reported that the north second rope has a large displacement, and the maintenance personnel found that the oil cylinder of the rope still has allowance, However, the phenomenon of rope movement does exist. After careful inspection, it was found that the rope adjusting oil cylinder of the north second rope on the side of the large tank leaked oil, and the "five-way valve" was connected to the oil cylinder Φ The valve core of 10mm ball valve is blocked, and the oil cylinders cannot be adjusted by passing liquid to each other. As a result, the north second oil cylinder and steel wire rope are not fully stressed, and the lifting rope swings greatly. This is the deficiency of the currently used "five-way valve": if any ball valve on the "five-way valve" is blocked, the oil of one oil cylinder cannot be adjusted with other oil cylinders, which is easy to cause the incomplete stress of a single lifting rope. This is also a direction in which we need to improve and innovate the "five-way valve" in the future.

5 Conclusion

The "five way valve" is used to adjust the auxiliary shaft rope adjusting oil cylinder, which can greatly facilitate the maintenance personnel to adjust the tank position in daily work, so as to handle or replace the fault of a single oil cylinder or a single rope, and the rope adjustment of multi rope friction hoist has strong operability, good applicability, safety and reliability, and does not need to increase too much transformation cost. In addition, if we can make some improvements on the basis of the "five way valve" currently used, such as adding auxiliary functions such as oil pressure display, it will be convenient for maintenance personnel to find problems in time and solve them quickly, so as to eliminate the hidden danger of rope channeling.