Friction and wear seriously affect the safety use of winding hoist wire rope and the damage is a gradual process in practical application. In this paper, the tribological properties of a wire rope under different sliding distances were investigated. The evolutions of the coefficient of friction (COF), temperature rise, and wear characteristics under different contact loads and strokes were analyzed by a series of experiments. The results show that fluctuation of the friction is large in the early stages (before 10 min) and the major peaks depend on the stroke. When the contact load is 150 N, the COF increases most rapidly. It grows from approximately 0.48 to approximately 0.61 with the sliding distance. Additionally, the temperature rise in the wear region is higher under the large stroke (30 mm) and contact load (150 N). The maximum temperature rises are approximately 7.5 °C and 7.1 °C, respectively. Furthermore, it is approximately after 7200 mm that the temperature rise reaches a relatively stable stage. The wear scar region increases with the sliding distance and the maximum wear loss is approximately 65.5 mg at a load of 150 N. The major wear mechanisms of the wire rope are fatigue and adhesion wear.

Surface wear is one of the major causes of damage to wire ropes in multilayer winding systems. This damage leads to performance degradation and affects the service safety of wire rope. To reveal the wear evolution and the performance degradation of wire rope in service, the correlations between the wear characteristic parameters and the residual strength were investigated. The results show that the variation in the wear parameters is affected by the wear distribution and the structure of the wire rope. The main wear mechanisms between wire ropes are adhesion wear and abrasive wear. Different wear parameters should be combined to evaluate the wear state of the wire rope. The tensile temperature rise could accurately reflect the wear evolution of the in-service wire rope under the condition of a large wear degree. The negative correlation between the residual strength and the wear area of the damaged rope samples is the strongest.

Surface wear caused by contact between crane wire rope and a pulley seriously affects the mechanical properties of the wire rope. In this study, the tribological behavior of wire rope was investigated using a homemade rope–pulley sliding friction test rig. Then, the influence of different surface wear on the bending fatigue life of the rope samples was analyzed. The results show that the friction coefficient (COF) decreases with the increasing sliding distance. It reaches a minimum of approximately 0.52 when the contact load is 700 N. The surface temperature of the wire rope rises rapidly and then gradually stabilizes. The maximum temperature rise fluctuates in the range of 50 °C to 60 °C with increasing contact load. The wear scar of the wire rope is irregular, and the maximum wear width increases from approximately 1.94 mm to 2.45 mm with the contact load. Additionally, increased contact load leads to smoother wear surface of wire rope, and the wear mechanisms are mainly abrasive wear and adhesive wear. Additionally, surface wear leads to a decrease in the bending fatigue life of wire ropes, and degradation of anti-bending fatigue is more serious under a larger sliding contact load.

In view of the serious friction and wear on the surface of a hoisting wire rope caused by the failure of lubrication under severe hoisting conditions, a study on the tribological characteristics of lanthanum stearate modified lubricating oil (LSMLO) was carried out. First, lanthanum stearate was prepared by the saponification reaction, and its surface morphology, chemical structure, thermal stability, and dispersion stability in IRIS-550A lubricating oil (IRIS) for wire rope were analyzed. Then, the tribological properties of LSMLO were investigated through four-ball friction tests and sliding wear tests of wire ropes. The results show that stearic acid almost completely reacts to produce lanthanum stearate, which has good thermal stability and a disordered layered structure. With the help of oleic acid, the dispersion stability of lanthanum stearate in IRIS can be significantly improved. The four-ball friction tests show that the optimal addition amount of lanthanum stearate in IRIS is 0.2 wt.%, and the CoF and wear scar diameter are reduced by about 35% and 25% respectively when lubricated with LSMLO compared to that with IRIS. LSMLO can better reduce the wear of the wire rope under different sliding speeds and contact loads than IRIS, and it exhibits improved anti-friction and anti-wear properties under high speed and low load.

Wire rope breakage, as damage easily produced during the service period of wire rope, is an important factor affecting the safe operation of elevators. Especially in the high-speed elevator operation process, the problem of magnetization unsaturation caused by speed effects can easily lead to deformation of the magnetic flux leakage detection signal, thereby affecting the accuracy and reliability of wire breakage quantitative detection. Therefore, this article focuses on the problem that existing wire rope detection methods cannot perform non-destructive testing on high-speed elevator wire ropes and conducts design and experimental research on a high-speed running wire rope breakage detection device based on the principle of multi-stage excitation. The main research content includes simulation research on the multistage excitation, structural design, and simulation optimization of open–close copper sheet magnetizers and the building of a detection device for wire rope breakage detection experimental research. The simulation and experimental results show that the multistage magnetization method can effectively solve the problem of magnetization unsaturation caused by the velocity effect. The multistage excitation device has a good wire breakage recognition effect for speeds less than or equal to 3 m/s. It can detect magnetic leakage signals with a minimum of four broken wires and has good detection accuracy. It is a new and effective wire breakage detection device for high-speed elevator wire rope, providing important technical support for the safe and reliable operation of high-speed elevators.

Wire rope has different degrees of surface wear under long-distance transmission conditions, which leads to performance degradation and greatly threatens its safety and reliability in service. In this paper, friction and wear tests between the transmission wire rope and sheave under different sliding velocities (from 0.8 m/s to 1.6 m/s) were carried out using a homemade test rig. The material of the steel wires was low carbon steel, and pulley material was ASTM A36 steel plate. The sliding friction coefficient (COF), friction temperature rise, wear characteristic parameters and wear mechanisms of the wire rope were analyzed. Additionally, the effect of different wear on the fracture behavior of the wire rope was investigated by a breaking tensile test. The results show that the average COF in the relatively stable stage decreased from approximately 0.58 to 0.51 with the increase of sliding velocity. The temperature rise of the wire rope increased rapidly with an increase of sliding velocity, from approximately 52.7 °C to 116.2 °C. The maximum wear width was the smallest when the sliding velocity was 1.2 m/s (approximately 1.5 mm). The surface wear was characterized by spalling, furrowing and plastic deformation, which are strongly affected by the sliding velocity. The wear mechanisms of the wire rope were mainly adhesive wear and abrasive wear. Surface wear changes the fracture morphology of the wire rope and accelerates its fracture speed.