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Safety Technical Operating Procedures for Winches: 1. It is necessary to regularly inspect the mechanical and electrical protection devices and interlock systems such as speed limits, deceleration mechanisms, over-winding protection, and brake pad wear, as well as to check the lubrication and tightening of all systems. II. Before starting up, check whether the hook, rope end, sheave, slide frame, steel wire rope, and braking device are sensitive and reliable. III. When the disc brake is fully released, the clearance between the brake pads and the braking elements should be within the range of 0.75–2 mm; the current in the movable coil shall not exceed 250 milliamps, and the oil pressure should be at the maximum operating level. During full braking, the brake pads must make good contact with the brake disc, and the pads must be free of cracks. The current in the movable coil should be “0”, and the residual pressure should not exceed 0.16–0.5 megapascals. IV. When the lift is fully released, the gap between the brake shoes and the brake ring should not exceed 2–3 mm. V. The brake shoes must be kept clean, free of oil or dirt. VI. Once the operating pressure of the hydraulic system has been set, the driver must not adjust it arbitrarily. VII. Before starting up, it is necessary to check and remove dust or dirt from the depth indicator drive mechanism as well as from all the impact plates. VIII. The over-winding protection device must be checked once per shift to ensure safety and reliability. IX. When ascending or descending, the start signal must be used in strict accordance with regulations; starting the operation is strictly prohibited if the signal is unclear. X. Maximum speed for lifting personnel in shafts using hoists: 1) When a guide rope is used, it shall not exceed 1/3 of the maximum lifting speed of the cage. 2) Without a guide rope, it shall not exceed 1 meter per second. 11. Maximum speed for lifting materials using a hoist bucket in deep shafts: When there is a guide rope, it shall not exceed 2/3 of the maximum lifting speed of the cage; when there is no guide rope, it shall not exceed 2 meters per second. 12. For hoists with mechanical braking, the lifting and lowering should be smooth to avoid shocks. 13. The time during which heavy objects are lowered with the brake in use should not be too long, and the maximum temperature of the brake pads must not exceed 100°C. 14. When lowering personnel and materials, the main motor must not operate with power disconnected. 15. If any of the following conditions are detected during operation, the machine must be stopped immediately for handling. 1) Over-winding or malfunction of the switch. 2) Failure of the over-speed or deceleration device. 3) Failure of the braking or interlocking device. 4) Abnormal odors and noises from mechanical or electrical components. 5) Abnormal readings of ammeters, voltmeters, oil pressure gauges, air pressure gauges, etc., and failure of other mechanical and electrical safety protection devices. 6) Abnormalities were found in the winding arrangement of the steel wire rope on the drum. 7) Unidentified signals appear. 8) No deceleration even upon approaching the wellhead. 9) Other serious unexpected failures, etc. 16. When stopping a hoist with mechanical braking, the control lever should first be moved to the middle position before applying the brake quickly. 17. For lifts in which the emergency brake and the service brake are controlled separately, when the brakes are released, the service brake must remain in a braked state. In case of an emergency, press the shutdown button or the foot-operated shutdown switch. If emergency braking does not work, the driver should promptly push upward on the locking pin on the cylinder to activate emergency braking.