Wire breaking occurred in the main rope of the aerial rope way, and some tests on wire breaking were tried, and results obtained are as follows.
1. Wire breaking appeared more quickly when hardness of one pulley was more higher than the others.
2. Wire breaking was retarded when sagging of main rope was small.
3. There were 2 sort of wire breaking viz., crack occurred first only in the upper side of wire and then breaking happened, and crack occurred both in the upper and lower sides of wire.
4. When material of pulley was made of soft metal, cracks occuring in the main rope wire were very few, so, breaking of wire was delayed and then increasing speed in the breakings of wire in a main rope was retarded.
5. Scanty strain was generated in the wire when soft roller was used, and when the hardness of roller was higher than that of the former larger strain was generated.
These results were obtained with pilot apparatus of aerial rope way 1st, 2nd and 4th nucha. 5th cervix was, obtained by wire testing machine which was designed by our college, and the 3rd cervix was obtained through these two testings.

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Several pieces of wire rope are used in the transport device of low noise elevator type mechanical parking system, EMPS. It is important to estimate the fatigue life of wire rope in order to keep the reliability of parking system. The formula proposed by G.Niemann in 1946, well known to be accurate in the fatigue life estimation of wire rope, has been modified and used in the design. But this formula has some problems such that it does not have the parameter of wire bending stress by sheaves, while the fatigue life depends on wire breakage by its repeated bending. In this paper, first, the damage mechanism and behavior of wire rope in this parking system were studied using the exchanged wire rope attained the criterion, 10% breakage of wire, and then the estimation method of fatigue life of wire rope is proposed, based on S-bend fatigue test simulated the actual condition, using the wire bending stress σ_b by sheaves and the fatigue strength reduction factor K_f which is related to the contact force P_UC with driving sheave as a function of wire rope tension.

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The impact test has practiced to investigate the decreasing trend of impact value and the maximum elongation rate, on deteriorated wire ropes which have damages such as corrosion, abrasion and wire breakage individually.
From the test, it has become clear that both the impact value and the maximum elongation rate decrease as deterioration of wire rope progresses, and that there is a certain relation between the decreasing trends of them. The relation is realized on both the deteriorated wire rope caused only by one type of damage defected artificially and the retired wire rope which has various types of damage.
The impact value is one of the characteristics that estimate the safety of wire rope, therefore, it seems possible to estimate the safety of wire rope based on the remaining ratio of the maximum elongation rate i. e. the remaining length against the allowable maximum elongation.
But, in case that tht sharp flaws and deteriorations which decrease cross-sectional area of the wire rope partially are recognized on the surface, it may be necessary to practice the manual inspection or some nondestructive testing methods, because the elongation of wire rope is not clearly realized in spite of sharp reduction of the cross-sectional area.

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It is said that shock load will causes winding ropes to break finally, therefor under shock condition, the shock absorbing capacities (=deformation energies) must be concidered necessary for safety and durability of winding ropes.
We studied the impact value of the corroded and weared wire ropes used in coal mines by mean of impact tensile breaking test.
From the test results, the following conclution were obtained.
The impact value of old winding ropes were more influenced and decreased by the decrement of effective sectional area than by that of static tensile strength.

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（以下，ロープ）は，クレーンやエレベータなどの機械構造物の主要部品の一つである．荷の巻上げ巻下げ時など，ロープは張力を受けながらシーブ上を往復動するため，曲げ負荷を繰り返し受ける．これにより，ロープを構成する素線が徐々に断線し，最終破断に至る．そのため，素線断線状態を考慮した保守，運用がロープの破断事故防止のために重要である．近年，クレーン用ロープの主流となっているIWRCロープについて，繰り返し曲げ負荷による素線断線が目視確認できないロープ内部で発生することが明らかになった．そのため，ロープ内部の素線断線の検出方法や断線メカニズムの解明に関する研究が進められている．一方で，ロープは複数の素線の撚り合わせによって構成されているため，ロープの軸方向に垂直な断面内での素線断線位置の特定が難しく，これまで詳細な評価が行われていなかった．そこで本研究では，ロープのS曲げ疲労試験によって作成した損傷ロープを対象に，近年提案された推定手法を用いてロープ断面内の位置を考慮した素線断線状態の評価を試みる．張力1水準，中断回数4水準のS曲げ疲労試験を実施し，得られた損傷ロープの素線断線分布の結果から，シーブ接触部や隣接する素線との位置関係によって素線断線しやすい条件があることを明らかにした．さらに，可視断線の発生メカニズム，現行の廃棄基準との関係についても考察した．

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The forming by manufacturing the wire rope for colliery and mining improves the properties of wire rope and shows many advantages in using. The forming is generally classified into preforming-forming before the closing and postforming-forming after the closing. There are various kinds of methods in each forming.
Hitherto the degree of forming in rope has been measured after breaking up rope. The authors invented the new method to measure the degree of forming undestructively with the special instrument that we named spiker.
Generally preforming has a tendency to remove the wave of rope, but practically the wave property varies with forming conditions even at a definite degree of forming. By preforming with roller type the wave property is greatly influenced by the distance between two rollers. Namely; when it is long, the wave of rope has the opposite direction to the lay of rope and with becoming shorter the wave is removed and further shows the same direction as the lay of rope.
When postforming by reverse bending, the direction and the degree of wave are influenced by the contact angle with roller and at a certain contact angle the wave is removed and the ro pe is straightened.
This study explains the relation between forming and wave of rope experimentally and theoretically.

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集材架線における架設作業を大幅に省力化・効率化することを目的に、現在使用されているなどの鋼製機材・器具を、より軽量な合成繊維素材に置き換えて架設する方法を検討した。新たに導入したのは超高重合度ポリエチレン繊維ロープと高強度ポリエステル繊維のベルト荷締機で、これらを使用した架設方法とを使用した従来の架設方法を比較した。調査地は群馬県沼田市の森林技術総合研修所林業機械化センターの実習林である。それぞれの方法について控索2本を模擬的に架設し、2組の作業者が方法ごとに1回ずつ架設と撤去を行った。作業の様子をビデオ撮影して作業時間の分析を行うとともに、作業者には心拍計を装着して作業中の心拍数の増加状況から労働負担を評価した。控索2本の架設に使用した資材の総重量は、繊維ロープ、ベルト荷締機、の順に軽かった。また架設作業時間については、1組は繊維ロープ、ベルト荷締機、の順に短く、もう1組はベルト荷締機、繊維ロープ、の順に短かった。このことから、合成繊維素材を使用した架設がに比べ有利であることが示唆された。

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We propose a new method of estimating the fatigue life of wire ropes of elevator. It is based on the assumption that the life of wire rope is determined by the fretting fatigue life of wires. Estimates done on a sample wire rope with the method were in good agreement with the experimental results. The method of estimation involves four steps. First, we did a finite element analysis and estimated the pressure between the wires. To take into account the behavior of the whole wire rope and each wire in the stress analysis, we did a zooming analysis. Second, we conducted a fretting fatigue test on the wires to construct a fretting fatigue database for them. Third, we estimated the life of each wire derived from the pressures between the wires and the fretting fatigue database. Last, we estimated the life of the wire ropes derived from the life of individual wires. The rope life estimated with our new method revealed some important findings. We found that : (1) the inner wires broke earlier than the outer wires and : (2) the residual strength of the wire ropes decreased rapidly after their strength became lower than 80% of their initial strength.

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It is very important for a cable puller to clarify the friction mechanism between a wire rope and steel grippers. In earlier works, some fundamental data such as friction coefficient, deformation and real contact area were obtained. This paper presents main factors affecting the friction based on the experiment varying apparent contact area and lubricants, and also observation of the deformation process. It is shown that the friction of the wire rope is hardly affected by the apparent contact area but significantly affected by the section shape of grippers. It is considered that high compressive load being mainly supported by 6 strands, rather than the rope core of a wire rope structure, is closely related to the friction mechanism.

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の寿命，安全率，劣化による強度低下などには多くの研究があるが，現場ではその結果がまだ十分に活用されていない．

ワイヤロープ

の切断事故は，機械の設計不良，安全装置の不良，運転操作のミス，玉掛作業の不良，劣化に対する点検不良，索端加工の不良，

ワイヤロープ

自身の欠陥などの諸要因が，多くの場合重複した結果発生している．そこで，昭和48年中に報告されたクレーン関係のワイヤロ一プ切断事故の中から，16件の事例を選んでその原因を検討し，今後の災害防止のための資料とする．

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To investigate tensile breaking factors and preventive methods on the polyamide monofilament line, the circularity and tensile strength were measured. We found out that the circularity is dispersive along the line, which lower the tensile strength and cause the line breaking by the stress concentration. When polyamide monofilament line is bent on swivel, tensile strength decreased as the decreasing of cross section area. We examined the tensile breaking factors theoretically, and then discussed some preventive methods of tensile breaking, i. e. vinyl tube, tapered polyamide monofilament, preventive frames installing on swivel and casting polyamide monofilament. The casting polyamide monofilament has special cross section, wears resisting and against damage, so it is suitable for the fishing operation.

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The crossover of ropes in many layers around a drum is analyzed on differential geometry and calculus of variation with movable boundaries. As a geometrically nonlinear problem for linearly elastic ropes, the center line of ropes is modeled as a space curve which is restricted by the surface of the first-layer rope. The bending stiffness, tensile force and friction force acting on the rope and geometrical parameters of the hoisting drum are taken into account. The virtual work of the non-conservative tensile force and the bending energy of the cross-over are expressed by the first and second fundamental forms of the restrictive surface. Thereby the variational equation and boundary conditions are obtained. By the transformation of variables, the Euler equation is changed into an implicit form of the variable, and the expression of crossover is obtained. An experiment measuring the central angle of the cross-over is made to examine the result of theoretical analysis.

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タワーヤーダ集材作業を行っている作業現場での使用劣化の状態を検出するために,著者らは永久磁石磁化方式とホールセンサ漏洩磁束検出方式を用いた探傷器を開発したが,今回,その探傷器を使用して,実際にタワーヤーダ集材作業を行っている現場での性能試験を行った。タワーヤーダシステムは,オーストリア製のコラーK303タワーヤーダとシェルパU型搬器で,そのは,スカイラインがIWRC6×S(19)の15mm,メインラインが6×7の9.5mm,ホールバックラインがIWRC6×S(19)の10mmである。これらのを対象に,おのおの150mにわたって漏洩磁束探傷を行った。その結果,の外部断線だけでなく,内部断線をも検出することができた。また,スカイラインの損傷箇所の中には,1より長さの中に素線断面積合計で最大21.65%にも達する断線箇所が発見された。

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