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Three test platforms for long-term continuous loading are adopted to test the actuator prototypes of the 500-meter aperture spherical radio telescope (FAST). However, the wire ropes that are the key components of these platforms often break during testing. The purpose of this paper is to present an effective dimension design method for these wire ropes. This method is based on fatigue reliability theory.

Three types of stresses are introduced into the total stress model of the wire rope according to the complicated stress conditions. The fatigue strength of the ropes is also discussed in this paper. Then, the total stress model and the results of fatigue strength analysis are applied to set the optimization function for these wire ropes. Subsequently, this optimization function is used to calculate the reliability of previously developed wire ropes in relation to the actuator test platform.

The wire rope is unreliable, which is a finding that corresponds to those of previous tests. Upon drawing the optimal curve from the optimization function (whose optimal objective is the wire diameter), a wire rope is optimized for the FAST actuator test platforms. Finally, this optimized rope is used on the new actuator test platform. No fracture phenomenon has been detected in tests conducted over the past six months.

The fatigue reliability theory-based optimization function for wire ropes can be adopted for the universal dimension design of other wire ropes.

Discusses the distress of mine rope‐wires, under the diverse states of stresses and strains of physical, chemical and mechanical origin. Mine rope‐wires undergo complicated cycles of stresses and strains inside the depth of coal and metal mines. This assumes special significance during summer inside the deeper mines. Summarizes recent studies in this field and compares their results.

This is the first of three articles dealing with this very important subject. In this part, the intention is to convince the reader, if he should need any convincing, of the vital necessity for correct wire rope lubrication. Part Two will deal with the duties and properties of wire rope lubricants. Part Three will cover the methods of application of wire rope lubricant and should be of interest to every large user of wire ropes.

The objective of this paper is to determine fretting parameters of hoisting rope according to the hoisting parameters in coalmine and to explore the effect of contact load on fretting-fatigue behavior of steel wires.

Based on the mechanical model of hoisting rope in coalmine, the dynamic tension simulation of hoisting rope was performed. Static equations of hoisting rope under tension and torsion and theories of contact mechanics were applied to obtain fretting parameters. Fretting-fatigue tests of steel wires at different contact loads were conducted using a fretting-fatigue test rig. The fretting regime, normalized tangential force and fretting-fatigue life were studied. The morphologies of fretting contact scars and fracture surfaces were observed by scanning electron microscopy and optical microscopy to examine wear and failure mechanisms.

Dynamic tension changes from 0 to 30,900 N. In outer strand layer, contact loads between steel wires in certain wire layers are 60.5 and 38.3 N compared with 378 and 102.7 N between wire layers; relative displacements between wires are 62.5 and 113.2 μm, respectively. Mixed fretting regimes develop in all cases. Increasing contact load decreases the stabilized relative slip and normalized tangential force, reduces the fretting fatigue life, induces accelerated adhesive wear and fatigue wear and results in rougher fracture surface topographies. In all cases, fretting zone induces crack initiation; crack propagation and rupture zones present brittle cleavage and longitudinal splitting, respectively.

This paper presents the systemic study on determination of fretting parameters of hoisting rope according to the hoisting parameters in coalmine and the fretting-fatigue behavior of its internal steel wires. The results of fretting-fatigue tests show that the increase of contact load decreases the stabilized relative slip in mixed fretting regime and normalized tangential force, reduces the fretting fatigue life, induces accelerated adhesive wear and fatigue wear and results in rougher fracture surface topographies.

The authors warrant that the paper is original submission and is not being submitted to any other journal. And the research does not involve confidentiality, copyright infringement, leaks and other issues, all the responsibilities that the authors will take.

The purpose of this paper is to demonstrate the application of analytical decision making during the selection of engineering entities in an engineering design setting.

The paper develops a quantitative method for wire rope selection and uses handbook data to demonstrate the use of the method in selecting a suitable type and size of wire rope for the hoisting/hauling mechanism of a hypothetical manual winch.

Wire rope data can be processed into forms that are more readily useable in a quantitative selection method. Moreover, computer software such as Microsoft Excel may be used in the selection process, so long as the data are in suitable form.

The selection of engineering entities often occurs in engineering design processes. An information processing approach to wire rope selection has been developed and demonstrated. The method demonstrated in this paper should be applicable in other situations in which a need for the selection of engineering entities arises.

The main purpose of this study was to evaluate the tensile strengths of JIS G3549 super high-strength steel strand wire ropes (1,570 MPa-class high-carbon steels) and wire rope open swaged socket connections at fire and post fire.

Steady-state tests from ambient temperature (20 °C) to 800 °C, transient-state tests under the allowable design tensile force and tensile tests in an ambient temperature environment after heating (heating temperatures of 200–800 °C) were conducted.

The tensile strengths of the wire rope and end-connection specimens at both fire and post fire were obtained. The steel wire rope specimens possessed larger reduction factors than general hot-rolled mild steels (JIS SS400) and high-strength steel bolts (JIS F10T). The end-connection specimens with sufficient socket lengths exhibited ductile fracture of the wire rope part at both fire and post fire; however, those with short socket lengths experienced a pull-out fracture at the socket.

The fundamental and important tensile test results of the super high-strength steel strand wire ropes (1,570 MPa-class high-carbon steels) and wire rope open swaged socket connections were accumulated at fire and post fire, and the fracture modes were clarified. The obtained test results contribute to fire resistance performance-based design of cable steel structures at fire and fire-damage investigations to consider their reusability post fire.

WIRE ropes are found in almost every industry. Short lengths are used on many fork lift trucks, cranes, and other hoisting machinery, long lengths, up to several miles, are used for aerial ropeways, in collieries, and on many kinds of hoisting and transporting equipment. In many cases long aerial ropeways provide the only means of transport across water, deserts, bogs and even mountains. They are costly to buy and replace and their breakdown can cause serious loss of production in addition to possible injury to personnel.

The purpose of this paper was to create conditions for the correct decision concerning an exchange of the used rope for a new one. A cognitive goal was to indicate the causes of its wear and determining its mechanism reliability and durability.

The magnetic, organoleptic and strength standard tests of lifting triangle-strand ropes of a mining hoist were carried out. This way the current state of the tested rope was defined.

On the basis of an analysis of the results of the performed tests: magnetic, organoleptic and fatigue tests, it can be said that the magnetic one is accurate enough only to indicate the place of the rope’s biggest weakening, though the degree of weakening is not defined precisely – with significant excess. The accurate rope’s destruction degree is indicated by the strength tests.

The results of described investigations can improve safety of the mining rope mechanisms operation, even for an increased resource.

The elementary wear processes, which are the basic reason for the destruction of the rope, are indicated. Rope destruction is caused mainly by tribological factors: abrasion, corrosion and fatigue wear. Magnetic tests are accurate enough only to indicate the place of the rope’s biggest weakening (qualitative index). Most precisely, the rope’s destruction degree (quantitative index) can be found by the strength tests.

Part One in this series appeared in our June issue and dealt with early and more recent investigations which have proved the importance of wire rope lubrication. Part Two (July issue) covered the duties and properties of wire rope lubricants.

In our previous article, we stressed the importance of lubricating wire ropes, both during manufacture and during subsequent service. We also pointed out that ropes having fibre cores need both internal and external lubrication. Most manufacturers lubricate their ropes, with or without fibre cores, at every stage of manufacture.