- Mar 24, 2018 -
The production technology and equipment
The production of steel wire ropes has three basic processes of wire rope production: drawing, twisting and stranding;
Materials: The wire rope drawing mentioned here refers to a kind of technological means that the raw material is pickled, phosphatized, shelled, opened, and pulled one or more times during the process to change its molecular structure to reach the target diameter.
The raw materials are ferrous metals ranging from 0.14 to 10.00 mm and nonferrous metals ranging from 0.01 to 16.00 mm in diameter.
Pickling: Washing the surface of steel wire rope with corrosive substances and rolling the skin with acid solution. It is also called shelling in the production process of steel wire ropes. It mainly strips the oxides of the high wire to prevent rust and other impurities from affecting the blanking and damage the drawing dies.
Phosphating: In general, the process of immersing a material in a phosphate solution to obtain a layer of a water-insoluble phosphate film prevents corrosion to some extent.
Bursting: A variety of shapes, such as holes, circles, squares, octagons, or other special shapes, through which various metal wires are drawn. When the metal forces through the die hole, the dimensions and shapes change.
Cold drawing: An ordinary round steel, which is forced through a hole smaller than its diameter, the diameter of the round bar will become smaller and the length will elongate. If such a process is repeated, the round bar will be Further smaller. After this plastic deformation occurs, the hardness of the steel increases, and the plasticity almost disappears. Where plasticity is not required, such steels may be used where strength is only required.
Tempering: Because the molecular structure of the steel wire has been destroyed, only tempering once again restores the internal structure of the steel wire to facilitate re-drawing, which is not easy to break, and the tensile strength that we can pull is what we are talking about. The strength is pulled out of the drawing and is not heat treated. This is the biggest difference between the wire rope process and the machining process. Strong degree:The higher the strength of 1470N/mm2, 1570N/mm2, 1670N/mm2, 1770N/mm2, 1870N/mm2, 1960N/mm2, the stronger the pulling force, but the poorer the toughness, so the appropriate strength should be selected in the wire rope selection. Can not blindly high-strength, high-strength steel wire rope is strong, but weak in terms of wear resistance and flexibility.
The type, structure and purpose of the strands The type, structure, raw materials and production process of the ropes depend on the application. The wire rope is usually made of carbon steel wire with a diameter of 0.1 to 6.0 mm. When the sealed and semi-sealed steel wire ropes are made, the types of Z-shaped steel wire ropes and other special steel wire ropes are divided according to the purpose: hanging ropes for suspension bridges and strands for mines, carrying ropes for aerial ropeways, traction ropes for transmission devices, elevator ropes Tying and tying goods with tie ropes. The variety of wire ropes is increasing and the structure is becoming more and more complex. In addition to various coated steel wires, stainless steel wires and bimetallic wires are also used. In order to ensure the safety and reliability of steel wire ropes, steel wire ropes are required to have sufficient strength, good flexibility, compactness, pressure resistance, abrasion resistance, corrosion resistance and fatigue resistance, among which strength is the most important.
The cross-section structure of the wire rope is slightly in contact with the round strands, the strands contact the round strands, the surface contacts the round strands, the special-shaped strands, the single-layer strands do not rotate, the seal and the flatness and the like. The surface contact of the round stock wire rope is based on the traction force of the ramming machine to draw the wire contact strand through the wire drawing die or the roller die. Through the die-drawing, there are two kinds of anti-corrosion measures, namely oil coating and plating coating, before and after deformation of the strand.
Oiling: All wire ropes must be oiled with fiber cores, oils are required to protect the fiber cores from rot, corrosion of steel wire, moisturize the fibers, and lubricate the wire ropes from the inside to apply oil to evenly coat all wire surfaces in the strands. A layer of rust-proof lubricating grease, in which the rubbing is used to improve the mine shaft with large mining ropes, it should be coated with black oil with increased grinding and strong water resistance; other uses are coated with strong film-forming properties, good rust-proof performance, It is also required that the oil layer be thin so that it can be kept clean during operation.
Plating: There are galvanized, aluminized, coated with nylon or plastic galvanized steel wire is first plated and then pulled out of the thin coating and steel wire after plating galvanized thick coating, thick plating mechanical properties than the light wire rope is reduced, should Use in severely corrosive environments. Aluminized steel wire rope is more corrosion-resistant, wear-resistant and heat-resistant than galvanized steel wire rope. It is mainly used for fishing trawl ships and mines containing H2S, etc. It is produced by plating and then drawing. Nylon or plastic coated wire ropes are used to coat ropes and coat them together. The former is used for static cables and the latter is used for moving cables.
Reeler: Rewind the wire reel on the spool of the stranding machine; it is also possible to reel the steel wire directly from the wire-drawing machine onto the spool. The strands will smash the steel wire into strands. There are basket-type baskets, shaft-type tubes, tubeless and double twisters. It is a schematic diagram of a 12-axis tubular stranding machine. 1 is an I-shaped wheel with a lower strand, 2 is a rotating cylinder, 12 I-wheels with full wire, 3 is a pressure-lined tile, 4 is Traction wheel, 5 is the take-up wheel of the upper strand. The barrel rotates one revolution. The length of the strand drawn by the traction wheel is the strand length of the strand.
The process of producing steel wire ropes by arranging the rope strands around the centerline of the rope core on the rope forming machine. The rope should be strictly in accordance with the provisions of the manufacturing process of wire rope. After the rope machine is selected, it should be carefully selected to match the rope stocks, stock specifications, and knots.
Structure, twist direction, length, etc. shall meet the requirements of the wire rope manufacturing card. After the stocks are selected, the stock-carrying sheaves are installed on the I-wheel wheel carrier of the rope machine. The installation of the I-shaped wheel, the threading method of the stock, the adjustment of the tanning parameters, and the tanning operations in the twining process are the same as those in the case of splitting. Combined ropes are different from ramets only in the tanning process. The tethering of steel wire ropes is divided into three types: single twist wire rope twisting, double twist wire rope twisting, and three twisted wire rope twisting.
The tantalum wire rope tanning method and the tanning process are basically the same as the tanning method and the tanning process of the same structure. The only difference is that in the single tether wire rope, the tantalum wire around each tantalum layer outside the core is alternated. The change is determined by the direction of the outer wire. The sealed wire rope is a single wire rope. The tanning method is similar to that of a single wire rope made of tantalum. The difference is that, when tanning, it must be ensured that the large surface of the shaped wire outside the rope core always faces the outer surface of the wire rope. The tanning of the profiled steel wire outside the sealed wire rope core is generally done on special equipment.
Double twist ropes are usually made from 2,3,4,6,7,8-strands. Up to 36 shares can be reached, with many varieties and complex structures. It is the most widely used wire rope. The most common application is a double strand wire rope consisting of 6 strands. Medium-sized twin stranded wire ropes can be manufactured using tubular stranding machines. Rough wire ropes, especially wire ropes with the same direction, are machined using a basket-type rope machine. Special-shaped strand steel wire rope can be made by special equipment, and it can also be converted into a special-shaped strand and made into a steel wire rope on a common rope machine. The surface contact wire rope can be manufactured by profiled steel wire rope tanning method or plastic compression method. The plastic compression method is to subject a round strand to drawing or rolling during the strands of the strands to cause plastic deformation of the strands in the strands, change the contact state of the strands in the strands, and then use the strands to make the ropes. The tanning of the three-wire rope is the same as the tanning of the twin rope, but the number of tanning times has increased.
All steel ropes should be made loose. The non-loose performance of the wire rope is achieved by pre-deforming the tantalum strands when the ropes are combined. Wire ropes of metal cords can also be heat-treated to obtain loose properties. In order to improve the mechanical properties and non-looseness of the wire rope, in addition to the pre-deformation of the strands when the ropes are combined, the stock straightening process is also widely used for the strands and the strands to eliminate the tanning stress of the wire ropes.
A wire rope coating tank is arranged between the traction wheel and the take-up device of the tie rope machine, and the wire rope is oiled. After the wire rope is oiled, it is evenly wound on the spool of the take-up mechanism by the wire arranging mechanism. After the tanning process is completed, the rope head of the wire rope is fastened with a soft wire and fixed on the spool.