57 results about "Breaking force" patented technology

The invention discloses a TBM hob three-way rock breaking force prediction method and system based on a rotary cutting mode, and the method comprises the steps: building a hyperbolic function model of the cutting edge width and penetration depth of a hob, and optimizing the geometric structure of the hob to adapt to different rock stratums; an effective contact radius and a contact angle are calculated through a coupling motion trail equation of revolution and rotation of the hob; fitting a pressure distribution coefficient in combination with pre-test data, constructing a Hertz-Weibull stress coupling analysis model, and accurately representing stress distribution in the cutting direction and the radial direction; on the basis of contact pressure integration and stress decomposition, respectively deriving explicit calculation formulas of vertical, rolling and lateral rock breaking forces, and dynamically adjusting the rotating speed of the cutterhead, the propelling pressure and the hob spacing according to a rock breaking force prediction result. According to the method, the rock breaking force prediction precision in the complex rock stratum is remarkably improved, the TBM construction efficiency and the cutter service life are optimized, the over-excavation risk and energy consumption are reduced, and the method is suitable for intelligent tunneling control of tunnel engineering.

The invention relates to the field of steel cord detection equipment, in particular to a manual detection device for the breaking force of a welding point of a steel cord. Comprising a workbench, a positioning sliding rail, a sliding buckle plate, a bearing box, a tension meter, a first clamping jaw, a connecting strip plate, a second clamping jaw, a supporting vertical plate, a positioning long box, a recording plate, limiting teeth, a marking pen, a locking insertion plate, a power mechanism used for driving the bearing box to move and a brake mechanism used for limiting movement of the bearing box, wherein the marking pen and the locking insertion plate are symmetrically arranged in the bearing box in a sliding mode. The power mechanism is provided with a pulling output end, the pulling output end is connected with the bearing box, the brake mechanism is provided with a transverse moving output end, the transverse moving output end is used for driving the locking insertion plate and the marking pen to stretch out or retract, and the first clamping jaw and the second clamping jaw are used for clamping a steel cord body. And the efficiency of detection work is improved.

The invention discloses a process for producing a tire bead wire by using a 70 # steel wire rod, the 70 # steel wire rod is used as a raw material, and the 70 # steel wire rod comprises the following components in percentage by mass: 0.70-0.72% of C, 0.20-0.22% of Si, 0.50-0.55% of Mn, less than or equal to 0.015% of P, less than or equal to 0.015% of S, less than or equal to 0.03% of Cr, less than or equal to 0.03% of Ni, less than or equal to 0.04% of Cu and the balance of Fe and inevitable impurities. The 70 # steel wire rod is used for replacing commonly-used 77A and C72DA tire bead grade wire rods, the application grade and cost of wire rod raw materials are reduced, the content of manganese and silicon elements is increased, the hardness and hardenability of the steel wire are enhanced, and the hot working performance of the steel wire is improved; meanwhile, the organization structure of the steel wire material is innovatively improved through the tempering process, it is guaranteed that the steel wire rod with the low application grade obtains high strength and toughness, and the key indexes such as the breaking force, the yield ratio and torsion of the steel wire rod are improved. While the strength requirement of the automobile tire is met, the process difficulty of raw material production is reduced, the energy consumption is saved from the source, and the emission of three wastes is reduced.

The present invention relates to the technical field of tungsten alloy materials, and particularly relates to a tungsten alloy wire and a preparation method and application thereof. In terms of mass fraction, the components of the tungsten alloy include: 0.3-0.75 wt% of element L, 0.001-0.18% of oxygen element, and the balance is tungsten element and inevitable impurities; wherein, L is one or more of lanthanum, cerium, praseodymium, neodymium, gadolinium, and erbium; the wire diameter of the wire is 0.3-0.6 mm; and in the wire, the average radial width of the tungsten fibers is ≤0.4 μm; the number of cracks per 100 meters of flaw detection on the surface of the wire is ≤5. The tungsten alloy wire provided by the present invention has finer internal tungsten fibers, the tungsten fibers are effectively strengthened and the density is improved, and the flaw detection number on the surface of the tungsten alloy wire is small; the effective strengthening of the internal tungsten fibers and the improvement of the density enable the medium-temperature breaking force, medium-temperature creep resistance and winding performance of the wire to be improved; therefore, when it is used as a tungsten wire rope for pulling single crystal silicon, both the reliability and the service life are improved.

The utility model relates to the technical field of breaking force testing clamps, in particular to a buckle type breaking force clamp which comprises a test board, a lower clamp and an upper clamp, the lower clamp is placed on the upper surface of the test board, an object containing groove is formed in the upper surface of the lower clamp, a lower fixing block is arranged on one side of the object containing groove, and a lower moving block is arranged on the other side of the object containing groove. One ends of the lower moving blocks are jointly connected with a first sliding block, a first lead screw is arranged on one side of the lower clamp, an upper fixing block is arranged on the lower surface of the upper clamp, a second sliding block is connected into the upper clamp in a sliding mode, the second sliding block is fixedly connected with an upper moving block, a filling block is arranged between the upper fixing block and the upper moving block, and a second lead screw is connected to one side of the second sliding block in a threaded screwing mode. By arranging the adjustable lower clamp and the adjustable upper clamp, the width of the storage groove can be flexibly adjusted so as to adapt to the widths of LED supports of different models, the whole clamp does not need to be frequently replaced, the number of clamps needing to be arranged is reduced, and the clamp arrangement cost is reduced.

A manufacturing method of a controllable constant-resistance deformation anchorage device comprises the following steps that S1, an anchorage device body with the length being L, the breaking force being Fb and the outer diameter being R1 is selected according to a current application scene; s2, a constant-pressure deformation sleeve is arranged on the outer side of the anchorage device body in a sleeving mode; the radial bearing force of the constant-pressure deformation sleeve is N, and N is smaller than Fb; s3, a lock is arranged at one end of the anchorage device body, and the constant-pressure deformation sleeve is moved to abut against the lock; s4, the end, away from the lock, of the anchorage device body penetrates through a ball pad, the inner diameter of the end, away from the lock, of the ball pad is R2, the inner diameter of the end, close to the lock, of the ball pad is R3, and the two sections of inner diameters are in smooth transition through a guide slope with the angle of alpha; the constant-pressure deformation sleeve is provided with a diagonal plane corresponding to the guide inclined plane, the radial force of the constant-pressure deformation sleeve is N, and N is smaller than necking force P; and S5, the end, away from the lock, of the anchorage device body penetrates through the tray, and the tray abuts against the end, away from the lock, of the ball pad. And the deformation of the constant-pressure deformation sleeve can be controlled under controllable conditions.

The invention discloses an anti-rebound strong-breaking high-voltage direct-current relay, and the relay comprises a static assembly which is disposed in a relay housing, is used for forming a static conductive and magnetic circuit foundation of the relay, provides a second section of counterforce in the pull-in process of the relay, inhibits the pull-in rebound of a contact, and assists in enhancing the breaking force during breaking. And the movable assembly is arranged in the relay shell and is used for realizing dynamic on-off actions of the contacts. According to the invention, the three-section counter-force design is optimized and combined with the tower-shaped spring, so that the collision energy and bounce of the movable contact can be reduced, the arc generation and the component loss are reduced, and the bonding risk is reduced; breaking force is provided through the synergistic effect of the main spring, the counter-force spring and the magnetic steel, the contact can be assisted to be rapidly separated, and therefore fusion welding is overcome, arc extinguishing is accelerated, and contact damage is reduced. Through the magnetic steel directional polarity and closed magnetic circuit design, the magnetic field intensity can be enhanced, the pull-in response time can be shortened, and the magnetic leakage can be reduced, so that the pull-in force and the holding force can be enhanced, and the contact looseness can be avoided.

The utility model discloses an annular hoisting belt with high breaking force, and relates to the technical field of hoisting belts, the annular hoisting belt with high breaking force comprises an annular hoisting belt body, a connecting rod is detachably mounted on the inner side of the annular hoisting belt body, a connecting piece is detachably mounted on the outer side of the connecting rod, and a hook is detachably mounted on the inner side of the connecting piece; the annular lifting belt body comprises a core layer, a tensile layer is arranged on the outer side of the core layer, and a wear-resistant protective layer formed by weaving fiber yarns in a criss-cross mode is arranged on the outer side of the tensile layer. The annular lifting belt with the high breaking force is sequentially made of the core layer, the tensile layer and the wear-resistant protective layer which is formed by weaving the fiber yarns in a criss-cross mode from inside to outside, the maximum bearing capacity under the action of tensile force is high, the annular lifting belt is not prone to breakage after being damaged, and safety is high.

The present invention relates to the technical field of steel cords, and in particular to a method for producing flat steel wires by a two-step method, the method comprising the following steps: a rough drawing process, an intermediate heat treatment process, an intermediate drawing process, a heat treatment electroplating process, a water tank process, and a two-step rolling process. The present invention adopts a two-step method to roll round steel wires into flat steel wires, and the compression rates of the two-step rolling processes are 15% and 16% respectively. The obtained flat steel wires have a breaking force greater than 300N and a two-way torsion greater than 50 times. By replacing one large deformation process with two small deformation processes, the deformation process of the steel wire is gentler, effectively alleviating the damage to the steel wire during the rolling process, reducing microcracks on the surface of the flat steel wire, significantly improving the breaking force and two-way torsion of the flat steel wire, and reducing the probability of the flat steel wire being broken during the stranding process.

The invention discloses a tool wear rule model construction method. The invention relates to the field of shield cutter wear rule research, and solves the problems that an existing method is complex in model construction, is easily interfered by working condition fluctuation in practical application, and is insufficient in prediction stability. The method comprises the following steps: acquiring wear loss data of a tool changing point of a practical engineering tool, and establishing a practical engineering wear rule model by using a K-means clustering and quadratic fitting method; based on a CSM model of approximate constant-section hob rock breaking force and a Rabinowicz abrasive wear equation, a theoretical model of a wear rule is established; establishing a blade yield strength change model for the blade yield strength in the theoretical model; and the blade width change model and the blade yield strength change model are added into the theoretical model to obtain a corrected tool wear rule model, and the model can provide accurate data support for tool replacement cycle planning in shield tunneling construction.

The present invention provides a method for manufacturing blades with a cutting edge from glass by subjecting a strip glass to a controlled breaking force. Before breaking the glass is scored to create a line of weakness at which the break is made. The glass is broken by striking the glass with a breaking force that causes the glass on either side of the score line to pivot away from one another. This controlled breaking of the glass strip creates a broken off portion of glass that has a sharp cutting edge. The present invention also provides an apparatus that creates glass blades in accordance with the method.

The process for improving the transverse breaking force of wrapping film belongs to the technical field of wrapping film and is prepared by a film blowing method and comprises the following steps: S1. preparing and weighing raw materials of different layers of ABCBA according to a proportion, uniformly mixing the raw materials to obtain raw materials of different film layers; S2. pouring the raw materials of different film layers into corresponding feeding machines of different extrusion layers, melt plasticizing, and co-extruding into a tubular die via a five-layer die; S3. blowing and shaping the tubular die, a blowing ratio of 2.3-2.5, and a longitudinal traction ratio of 1.9-2.1; S4. after cooling, traction and winding, and placing at 25-28 DEG C for 4-8 h, a finished wrapping film is obtained. The application enables the molecular chain to be fully stretched and oriented in the transverse direction by designing a blowing ratio of 2.3-2.5 and a traction ratio of 1.9-2.1, while inhibiting excessive orientation in the longitudinal direction, so that the mechanical properties are more balanced; and the application enhances the overall transverse breaking force of the wrapping film by cooperating with a five-layer structure component enhancement system, thereby improving the tear resistance of the film and preventing the film from being easily torn during the packaging process.

The invention relates to the technical field of silk thread breaking force detection, in particular to a silk thread breaking force detection mechanism which comprises a base, a torque sensor and a breaking force assembly, the torque sensor is arranged on one side of the top of the base and used for continuously reading a tensioned silk thread, and when the silk thread breaking grabbing maximum detection value is a breaking force result, the breaking force assembly is used for detecting breaking force of the silk thread. The breaking force assembly is arranged on the base and used for detecting the breaking force by exerting pulling force on the silk yarn, and the breaking force assembly comprises a limiting base arranged at the bottom of the torque sensor and fixed to the base and a movable base arranged at the bottom of the limiting base. According to the invention, it is helpful for ensuring uniform distribution of stress when the silk thread is pulled, detection result deviation caused by non-uniform stress is avoided, the measurement precision of breaking force is further improved, the silk thread is more firmly fixed in the clamp, the contact force between the silk thread and the clamp can be enhanced, the risk of silk thread slipping is reduced, and the service life of the silk thread is prolonged. Therefore, the detection reliability is improved, and the test efficiency and continuity are improved.

The invention discloses a power transmission conductor fracture risk early warning method and device based on a forest fire condition, terminal equipment and a storage medium. Simulation calculation is performed based on a convective heat transfer model between a power transmission conductor and air, a heat conduction model between an aluminum wire and a steel strand and the surface temperature of the power transmission conductor; evaluating the temperature of each aluminum wire and each steel strand in the inner layer and the outer layer of the transmission conductor; according to the temperature of each aluminum wire and the temperature of each steel strand and the preset tensile strength of each aluminum wire and the preset tensile strength of each steel strand when the mountain fire does not occur, after the tensile strength corresponding to each aluminum wire and each steel strand in the current mountain fire area is obtained, the tensile strength of each aluminum wire and each steel strand in the current mountain fire area is calculated based on the total number of the aluminum wires and the steel strands and the tensile strength of the aluminum wires and the steel strands; according to the method, the third tensile strength corresponding to the power transmission conductor in the current mountain fire area is comprehensively evaluated according to the first tensile strength of the power transmission conductor and the structural parameters and the thermal expansion performance parameters of the power transmission conductor, and accurate early warning of the fracture risk is achieved by simulating the heat exchange process between the conductor and the surrounding environment under the mountain fire condition.

The invention relates to an ultrathin chemically tempered glass article having a thickness of less than or equal to 0.4 mm. In order to improve sharp object contact resistance, the glass article has a rupture force (given in N) greater than 30 times the thickness (t) of the glass article (t given in mm). Further, the glass article has a fracture bending radius (given in mm) less than 100,000 multiplied by the thickness (t) of the glass article (t given in mm) divided by the value of surface compressive stress (in MPa) at the first surface.

The present invention provides a finite element-based testing device and method for the breaking force of a tire bead wire ring. The device comprises an annular mold and a bead wire ring cross-section acting force extractor; the outer surface of the annular mold is provided with a mold groove, and the mold groove is used for accommodating a bead wire ring; the inner surface of the annular mold is provided with a load surface, and the load surface is used for expanding the annular mold to apply a breaking force to the bead wire ring; the bead wire ring cross-section acting force extractor is used for reading the acting force on a cross-section of the bead wire ring and testing the breaking force of the bead wire ring. In the present invention, the annular mold is expanded to apply an acting force to a bead wire ring, to simulate service conditions of the bead wire ring and more accurately evaluate the breaking force of the bead wire ring; by applying annular expansion displacement fields to the bottom surface of the annular mold and imposing displacement constraints on the annular mold, deviation of the annular mold is restricted.

A tire (1) for a mine engineering vehicle comprises two protective layers (31) having elastic metal reinforcements, the modulus of extension of which is at least 40 GPa and at most 140 GPa, and two working layers. The breaking force FR of the metal reinforcements of the radially outermost protective layer (311) is at least 2500 N, their pitches, in mm, being greater than 0.70 * FR / 1000 where FR is in N. The metal reinforcements of the radially outermost protective layer (311) form an angle APN with a circumferential direction (XX ') tangential to the circumference of the tire, the absolute value of the angle APN being at least 45°.

The present application relates to the field of exhaust pressure relief of closed space and device, and particularly relates to a tensile type pressure relief exhaust cover structure, which comprises a blasting tensile screw rod, a nut, a gasket, a cross support frame, a fence base, a device shell, a sealing gasket, an exhaust cover plate, a screw plug, a swing arm, a rotating shaft and a support, the fence base is arranged on the device shell, the exhaust cover plate is arranged on one side of the fence base and is used for closing the device shell, the blasting tensile screw rod is used as a locking piece and a trigger breaking piece of the exhaust cover plate, the blasting tensile screw rod is controlled in the tensile breaking time by the tensile strength limit of the middle diameter reducing section, when the internal pressure of the device is increased and is converted into the axial tension of the blasting tensile screw rod through the exhaust cover plate, the blasting tensile screw rod can be broken at the diameter reducing section when the preset breaking force is reached, the breaking force and the corresponding pressure relief pressure value can be accurately set by adjusting the cross section area of the diameter reducing section, and the opening pressure control precision is good.

The utility model discloses a paste fixing device and a breaking force detection device. The paste fixing device comprises a first end part fixing structure, a second end part fixing structure and a probe moving channel, the first end part fixing structure and the second end part fixing structure are arranged at an interval in a first direction, the first end part fixing structure is used for fixing one end of a to-be-detected paste body, and the second end part fixing structure is used for fixing the other end of the to-be-detected paste body, so that the to-be-detected paste body is erected between the first end part fixing structure and the second end part fixing structure; a probe moving channel extending in the second direction is arranged between the first end part fixing structure and the second end part fixing structure, and the two ends of the probe moving channel in the first direction are correspondingly communicated with the first end part fixing structure and the second end part fixing structure respectively; the first direction is perpendicular to the second direction. According to the paste fixing device, more stable breaking force data with smaller fluctuation can be obtained by changing the fixing mode of the paste.

The invention discloses a forty-two steel cord for an engineering tire, and belongs to the technical field of steel cord manufacturing. The steel cord comprises a core strand plied yarn, five outer-layer plied yarns and an outer wrapping wire, and the core strand plied yarn comprises a core strand first-layer monofilament and six core strand second-layer monofilaments woven and twisted around the core strand first-layer monofilament. The outer-layer strand yarn comprises an outer-layer strand first-layer monofilament and six outer-layer strand second-layer monofilaments which are twisted around the outer-layer strand first-layer monofilament, and gaps exist between the outer-layer strand yarn and the outer-layer strand yarn and between the outer-layer strand second-layer monofilaments. Through the structural design, the gaps between the outer-layer strand wires and between the outer-layer strand monofilaments are increased, the performance of well improving the rubber permeability is achieved, meanwhile, under the condition that the number of steel wires of the outer-layer strand wires is reduced, the breaking force of the steel cord is kept, the tire has higher bearing capacity, and the comprehensive performance of the engineering machinery radial tire is improved.

The utility model relates to connecting rod expansion breaking equipment which comprises a base, a pressing mechanism, a moving mechanism, a movable and fixed sleeve and a pull rod, before the connecting rod expansion breaking process, the large end of a connecting rod is arranged on the periphery of the movable and fixed sleeve in a sleeved mode, the pressing mechanism abuts against bolt supporting faces on the two sides of the large end of the connecting rod, and at least part of the pull rod penetrates into the movable and fixed sleeve. The pull rod is provided with a first abutting face facing the moving mechanism, the movable and fixed sleeve is provided with a second abutting face, and when the connecting rod is fractured, force applied by the first abutting face to the second abutting face can drive part of the fractured connecting rod to drive the moving mechanism to move relative to the base. The moving direction is the same as the force applying direction of the first abutting face to the second abutting face and the force applying direction of the pressing mechanism to the connecting rod, the situation that most of the force borne by the expansion breaking end of the connecting rod and the force applied by the pressing mechanism to the connecting rod are mutually counteracted is avoided, and therefore the effective expansion breaking force is improved; and therefore, chippings generated due to the unsmooth expansion breaking process are reduced, and the product quality of expansion breaking of the connecting rod is effectively improved.

This invention relates to a soluble bridge plug for casing-modified wells. The soluble bridge plug includes a soluble ball, a release ring, a central tube, slips, a rubber sleeve, and a guide shoe. The setting sleeve pushes the slips, guide block, slips, cone, extension body, secondary cone, rubber sleeve, and back ring downwards. The extension body expands radially under force, and the rubber sleeve and back ring expand radially as they descend, sealing the annulus between the central tube and the casing. When the starting force of the slips ring is reached, the slips expand radially. When the slips move to the outer diameter of the cone, they continue to move radially through the expanded outer cone surface of the extension until they bite into the inner wall of the casing, forming a self-locking mechanism. When the force generated by the setting tool reaches the thread breaking force of the release ring, the setting tool disengages from the bridge plug, completing the setting process. When fracturing of the producing layer above the bridge plug is required, the soluble ball is placed into the cone hole of the central tube, sealed, and then fracturing is performed. After fracturing, the soluble ball will dissolve under certain conditions, forming a full-bore channel inside the casing.

According to the method for improving the train wind-induced vibration resistance of the overhead line system additional wire, the tension setting of the additional wire is adjusted by generating the installation curve of the additional wire, and it is ensured that the safety coefficient about the maximum breaking force within the service temperature range reaches the standard; the train wind power spectrum is applied to an additional wire simulation model considering tension setting and wire clamp setting; the tension of the additional wire is adjusted with the purpose of reducing the maximum stress in the wind-induced vibration process of the additional wire; then optimizing the type of the additional wire clamp; obtaining optimization results of the tension and the wire clamp type; the train wind-induced vibration resistance of the additional wire can be enhanced, so that the risk of fatigue accidents of the high-speed contact network additional wire and parts thereof is reduced, and the safety and reliability of high-speed rail operation are improved.

The present specification discloses a kind of mining spherical step anchor device, which is the equipment for anchoring prestressed anchor cable, suitable for Ф21.8mm 1860MPa grade roadway support steel strand, compact structure, anchoring is reliable.The anchor device is mainly composed of anchor ring and three pieces of bevel type working clamping piece, the anchor ring has spherical end face, cooperates with tray with spherical groove, outer side is equipped with arc stepped skirt, the inner side of working clamping piece has inner tooth, and anchoring is realized by the positive pressure extrusion of anchor ring inner taper hole and clamping piece outer taper.Its static load anchoring efficiency coefficient is greater than or equal to 95%, the total elongation of assembly part is greater than or equal to 2.0%, anchor mouth friction loss is less than 6%, can withstand 2 million times of cyclic load, when installing, use mining anchor cable tensioning machine, tensioning force is 50%-60% of steel strand breaking force or according to the provisions, must not be reused and mixed with other manufacturers' products.

The application relates to the field of steel cord detection equipment, in particular to a steel cord welding point breaking force manual detection device, which comprises a workbench, a positioning sliding rail, a sliding buckle plate, a bearing box, a tension meter, a first clamping jaw, a connecting strip plate, a second clamping jaw, a supporting vertical plate, a positioning long box, a recording plate, a limiting tooth, two symmetrical sliding mark pens arranged in the bearing box and a locking plug plate, a power mechanism for driving the bearing box to move and a brake mechanism for limiting the movement of the bearing box, the power mechanism is provided with a pulling output end, the pulling output end is connected with the bearing box, the brake mechanism is provided with a transverse output end, the transverse output end is used for driving the locking plug plate and the mark pen to extend or retract, and the first clamping jaw and the second clamping jaw are used for clamping a steel cord body. The device can quickly realize the breaking force detection of the steel cord welding point and improve the detection efficiency.

The method for preparing a steel cord for a tire skeleton reinforcement material adopts a raw material with a low carbon content and adds chromium and vanadium alloy elements. Due to the reduced carbon content, mold loss can be reduced and product surface quality can be improved during the early drawing process. The added chromium and vanadium alloy elements refine the grains of the steel wire, strengthen the grain boundaries, improve the thermal strength and hardenability, and provide certain corrosion resistance. On this basis, combined with the control of the steel wire structure morphology during the process, it is ensured that the strength and breaking force of the steel wire are the same as those of the original process when the carbon content is reduced. Due to the improved early drawing performance, the wire breakage rate in the entire production process is reduced, the product quality is improved, and the production cost is reduced.

The utility model relates to the technical field of building material detection, and discloses a tension test device for building material detection, which comprises a test cabinet and a protective cover fixedly arranged in the test cabinet, and is characterized in that firstly, two ends of a building material to be tested are respectively fixedly clamped at the lower end of a threaded rod and the upper end of a placement block through clamping assemblies; after the building materials are clamped and fixed, a motor can drive a threaded rod to rotate, a clamping assembly at the lower end of the threaded rod is driven to move upwards, and along with rotation of the threaded rod, the motor can move upwards along fixing plates on the two sides through a connecting plate; the clamping assembly at the lower end of the threaded rod cannot cause upward bouncing of the device due to sudden disappearance of force at the lower end, when the tension test device for building material detection is actually used, tension detection can be performed on a building material through rotation of the threaded rod, and when the test material reaches a critical point and is suddenly broken, the device is not prone to bouncing. And displacement of the whole device caused by tensile strength is avoided.

The invention relates to a cable system for securing a floating platform to an underwater attachment point, wherein: the cable system is composed of an inner cable and an outer sheath cable designed as a sheath; the inner cable is formed of synthetic textile fibres; the sheath cable is braided from synthetic textile fibres; the inner cable is arranged in a tubular interior of the sheath cable; the inner cable has a first breaking force; and the sheath cable has a second breaking force which is greater than the first breaking force.

The invention discloses a large-span roof steel truss hoisting construction method which comprises the following steps: determining the foundation bearing capacity of a host installation operation site area, selecting a crane model according to the hoisting height, the operation radius and the weight of a hoisted object, and determining a hoisting scheme according to the site condition after selection; calculating a steel wire rope breaking force, and selecting a steel wire rope model according to the steel wire rope breaking force T; and according to the hoisting scheme and the breaking force T of the steel wire rope, a special construction scheme for steel truss installation operation is formulated, steel truss hoisting work is conducted according to the special construction scheme for steel truss installation operation, and welding and paint repairing are conducted after hoisting is completed. Standardized comprehensive hoisting of the large-span roof steel truss of the high-rise building is achieved.