Patent Publication Number: US-2013248638-A1

Title: Method for Horizontally Winding and Unwinding a Parallel Wire Strand

Description:
FIELD OF THE INVENTION 
     The present invention relates to a parallel wire strand consisting of a multiplicity of individual wires. More particular, the invention relates to horizontally winding and unwinding a parallel wire strand consisting of a multiplicity of individual wires onto and from a cable reel for fanning out and rearranging the wire strands for transport, storage or installation. 
     BACKGROUND OF THE INVENTION 
     The main cable strands are the chief bearing members of suspension bridge. The cable strand is made of high strength galvanized wire of 5 mm in diameter. Formerly specifications for the cable strand were available in 61 wires, 91 wires and 127 wires. At present the over-length large main cable strands reach 5000 m in length, in 169 wires of 5 mm diameter. The weight of a cable strand reaches 120 tons. Commonly the cross-section of cable strand is regular hexagon. Some special cable strands may be rectangular or other shapes. A cable strand is bound with composite material bands at interval of 1.5 m˜2 m. Traditionally, the winding of main cable strands of suspension bridge all applied large diameter steel reels for winding horizontal parallel wire strands at home and abroad. This process is called by reel processing for short. The one of the characteristics of reel processing was that the manufacturing, shipping and unwinding of cable strands all could not get rid of large diameter steel reel. During the transportation of cable strands on steel reels to large bridge building site, cable strands could give birth to oval traumas from falling down shown in  FIG. 1 , owing to their deadweight. Consequently the cable strands oval traumas from falling down therefore caused cable strand winding loosen and friction between cable strands generated by steel reel rotating. While cable strands were winding along with steel reel rotating continually, this kind of trauma from falling down could result in so-called “Hula-circles” effect, in consequence it disturbed the original arrangement order and could be very difficult to unwinding cable strand from steel reel. Furthermore, in unwinding cable strand the dragging and pulling forces suddenly made the loose cable strands to be tightened or loosened every now and then, which could aggravate the frictions between cable strands and scratch band on strand until breakage and make cable strand steel wires incoherent. During the procedure of unwinding cable strands the “Hula-circles” which had emerged would become more and more bigger along with the unwinding process of cable strands, its loosen amount would increase gradually, and cable strand would collide with ground, until unwinding job implementation had no means of normal proceed. In order to remedy this phenomenon in construction site it was necessary to reshape and bind strands continually by labor. Therefore the working machines should be shut down, after tightening cable strands wires, proceeded with unwinding strand for those already formative “Hula-circles”. This not only brought unlimited inconvenience to assembly molding of main cable of suspension bridge, but also more seriously influence the time limit for a project. Particularly the longer the cable strand, the more serious the “Hula-circles” developed, furthermore the longer the cable strand, the more difficult the remedy measures carried out, even could not carry out. According to experiences under the precondition of holding good cable strand shape, adopting reel processing technology, commonly when cable strand length is over 1500 m, “Hula-circles” will be easy to appear during unwinding process of cable strand. When the “Hula-circles” phenomena become serious, it will direct influence site construction schedule and cable strand quality. 
     SUMMARY OF THE INVENTION 
     A primary and general object of the present invention is to overcome the aforementioned drawbacks by providing a method for horizontally winding and unwinding a parallel wire strand with high working efficiency, fine quality of winding and unwinding cable strands and low labor intensity. 
     To this end, according to present invention, a method for horizontally winding and horizontally unwinding a parallel wire strand is disclosed. 
     A method for horizontally winding and horizontally unwinding a parallel wire strand upon a base of a cable reel for transport, storage or installation, a parallel wire strand made up of a plurality of tightly adjacent vertically and horizontally arranged parallel wires, the strand including at least a leading end fitting securing the ends of the wires together, is characterized in that the method comprises the following steps: 
     (a) Performing the winding operation, the operation procedure is as follows: 
     Fix the guide frame on the ground, the guide frame is composed of the base, support frame, electric hoist, fixed pulley, steel wire rope, lifting mechanism, roller, the pressure sensor, speed encoder, altimeter encoder and limit roller. Fix the base on the ground and fix the support frame and electric hoist on the base. A fixed pulley is equipped at the top of the support frame, also a steel wire rope which one end is connected with electric hoist and the other end is connected with lifting mechanism is winded on the fixed pulley. The lifting mechanism is equipped with three rollers, 2 pressure sensors and a speed encoder, the 3 rollers are arranged in “ ” shape, and that is, three straight lines connecting the circle center points of three rollers make up of a triangle. A pressure sensor and a speed encoder are equipped at one side of the three rollers, at the side of the fixed pulley, altimeter encoder, electric hoist, pressure sensor, speed encoder are equipped. Both the speed encoder and the altimeter encoder are connected with the programmable logical controller (hereinafter referred to as PLC) by the telecommunication wires. Fix the rotation axis on the ground at one side of the guide frame, connecting the rotation platform with the rotation axis; meantime, the rotating platform rotating about the rotation axis  21 . The upper surface of the rotation platform shall be flush with the ground, the platform rail is paved on the rotation platform and the railcar is located on the rail. To The characteristics of rotation platform facilitate the rail platform car easy to select multi-directions and link up with workshop rails. 
     The inner module is composed at least by four support plates and the support rod at the top section, the four support plates were aligned uniformly in the ring shape. There is a gap between the adjacent supports plates, the gap length shall be the width of the support plate of 80% to 150%. Operator can get into the inner module to operate through gaps between support plates. The support rod shall be fixed by the hinge at the top of the support plate, each support plate shall fix two support rods and the two top rods shall be symmetrically fixed on the support plate at left and right sides. The bottom of supporting plate and the railcar are connected by the bolt. The top support plate will lean outward. After fixing the support plate and railcar, the centers of gravity of four support plates should be located outside of each hinge. 
     Put a ring shape tray onto the railcar and hitch it outside the inner module. Lifting points which are used for lifting the tray and looped cable strands which are winded on the tray shall be set at the tray edges, and lay the water proof film covered on the surface of the tray. 
     Put one end of strand through the guide rollers and fix it onto the inner module, then drive rotation platform to rotate, which will drive the railcar and inner module to rotate together. Along with the rotation, the strand will be winded on the inner module one circle by another from the bottom end of the inner module till to the top of the inner module, and then wind the strand from the top of the inner module to the bottom. Repeat this operation until all the strands wrapped into wire strands. During the upward winding procedure, the PLC will control the electric hoist to pull the steel wire rope, thus to lift the lifting mechanism which will enable the guide roller to move upward with the distance which is equivalent to the strand diameter during each circle. During the downward winding procedure, the PLC will control the electric hoist to pull to steel wire rope, thus to pull down the lifting mechanism which will enable the guide roller to move downward with the distance which is equivalent to the strand diameter during each circle, therefore this guarantees that strands are capable of arranging on the inner module regularly and compactly. 
     After all the strands are winded into wire strands, dismantle the bolts between the bottom of the inner module and the railcar. Lift the support rod on the inner module which will make the 4 pieces support plates gather together inward, and then extract the inner module from the wire strands. After this, use the prepared waterproof film on the tray to cover the whole outside surface of the wire strand. Connect the platform track on the rotating platform with the track on the ground, pull the railcar to remove the wire strand, until this, the strand winding operation is finished. 
     (b) Performing the unwinding operation, the operation procedure is as follows: 
     Fix the guide frame on the ground, the guide frame is composed by the base, support frame, electric hoist, fixed pulley, steel wire rope, lifting mechanism, roller, the pressure sensor, speed encoder, altimeter encoder and limit roller. Fix the base on the ground and fix the support frame and electric hoist on the base. A fixed pulley shall be equipped at the top of the support frame, also the steel wire rope whose one end is connected with electric hoist and the other end is connected with lifting mechanism shall be winded on the fixed pulley. The lifting mechanism is equipped with 3 rollers, 2 pressure sensors and a speed encoder. The 3 Rollers are arranged in “ ” shape, that is, three straight lines connecting the circle center points of three rollers make up of a triangle. A pressure sensor and a speed encoder shall be equipped at one side of the three rollers, altimeter encoder at the side of the fixed pulley, electric hoist, pressure sensor, speed encoder shall be equipped. Both the speed encoder and the altimeter encoder shall be connected with PLC by the telecommunication wires. Fix the rotation axis on the ground at one side of the guide frame, connecting the rotation platform with the rotation axis, meantime, the rotating platform will rotate around the rotation axis. The hydraulic brake which is connected with PLC through pressure sensor is equipped in the rotation axis. During the rotation of the rotating platform, release the hydraulic brake. When the rotating platform stops, the hydraulic brake is always imposing friction on the rotating platform, thus applying portion of reverse compression to prevent against rotating platform continually rotating, bring about cable strand dropped out and damaged when dragging forces temporarily stop. 
     The inner module is composed by at least four support plates. The four support plates are aligned uniformly in the ring shape. The gaps shall be retained between the adjacent supports plates, the gap length shall be the width of the support plate of 80% to 150%. The bottoms of the support plates are connected by the hinge with the rotating platform, all the 4 pieces support plates will lean inward. In the middle of the 4 pieces support plates, a hydraulic jack is equipped. The support rod of the hydraulic jack is connected with four pieces push rods, and each push rod shall withstand a piece of support plate. 
     Remove the waterproof film cover from the strand, lift the strand wire strands together with the tray onto the rotating platform, meantime, and set the strand wire strands over the inner module. Actuate the hydraulic jack, with the force of the support rod applied to the push rod, the 4 pieces support plates will push outward by the push rod which will fix the strand wire strands. Pull one leading end of the strand throughout of the guide roller, then pull the strand to drive the inner module and the tray to rotate, thus to drive the rotating platform to rotate around the rotation axis. Along with this operation, the strand shall be released and become straight status. 
     During the downward winding procedure, the PLC will control the electric hoist to pull to steel wire rope, thus to pull down the lifting mechanism which will enable the guide roller move downward with the distance which is equivalent to the strand diameter during each circle. During the upward winding procedure, the PLC will control the electric hoist to pull the steel wire rope, thus to lift the lifting mechanism which will enable the guide roller move upward with the distance which is equivalent to the strand diameter during each circle. Repeat these operations back and forth till the wire strands become straight status, and fulfill the whole unwinding operation. 
     The method in accordance with the present invention is characterized in that the rotation axis is vertical to the ground at the side of the guide frame. 
     Further the method in accordance with the present invention is characterized in that in horizontal winding operation the bottom of the support plate is connected with the railcar by bolts, the top of the support plate shall lean outward and the angle between the support plate and upper surface of railcar is between 60°˜85°. 
     Further the method in accordance with the present invention is characterized in that in horizontal unwinding operation the bottom of the support plate is connected with the rotating platform by the hinge, all the 4 pieces support plate will lean inward and the angle between the support plate and upper surface of railcar is between 60°˜85°. 
     Under the controlling action of the PLC, the unwinding of cable strand is restricted to prevent against out of control for strand, avoiding cable strand damage or injury or loss; in unwinding strand operation, can keep line shape relatively straight and level to protect strand and prevent binding band breakdown, when the speed of unwinding strand is slowed down or stop, gradually control hydraulic brake to lock turning axle; the introduction of pressure sensor furthermore facilitates PLC to control hydraulic brake smoothly. 
     Thus according to the invention it is possible to solve the “Hula-circles” effect problem, and remarkably increase cable strand erection benefits and cable strand quality of carrying out the method of the invention. The advantages of present invention are: reasonable arrangement of operating sequence, winding strand, strand wire strands formation, package and transportation, as well as unwinding complete in one breath, reduce labor intensity and operation time; cable strand wire strands formation compact and regular arrangement; winding strand and unwinding strand all may be able to go with a swing; when unwinding strand trauma from falling down phenomena is eliminated, unable to damage cable strand and binding band; Increase automaticity, equipments are controllable and tunable, real-time monitoring correlated data, reduce labor intensity, increase security; shipping reel simplicity and removable, have no use for large size reel, save a great deal of manufacture and transportation costs. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a structure schematic for the strand drop phenomenon in the existing technology; 
         FIG. 2  is a structure schematic for strand winding on the inner module when winding strand; 
         FIG. 3  is the front view of the guide frame in this invention; 
         FIG. 4  is the left view of the guide frame in this invention, 
         FIG. 5  is a structure schematic for extraction of the inner module when winding strand finished, 
         FIG. 6  is a structure schematic for straighten of the strand wire strands when unwinding strand. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS OF THE INVENTION 
     The accompanying drawings and description herein-below disclose embodiments suitable for carrying out the method of the invention. 
     Embodiment 1 
     A method for horizontally winding and horizontally unwinding a parallel wire strand upon a base of a cable reel for transport, storage or installation, a parallel wire strand made up of a plurality of tightly adjacent vertically and horizontally arranged parallel wires, the strand including at least a leading end fitting securing the ends of the wires together, comprising the steps of: 
     (a) Performing the winding operation, the operation procedure is as follows: 
     As shown in  FIG. 2 , fix the guide frame  1  on the ground, the guide frame  1  is composed by the base  11 , support frame  12 , electric hoist  13 , fixed pulley  14 , steel wire rope  15 , lifting mechanism  16 , roller  17 , the pressure sensor  181 , speed encoder  182 , altimeter encoder  183  and limit roller  19  as shown in  FIGS. 3 and 4 . Fix the base  1  on the ground and fix the support frame  12  and electric hoist  13  on the base  1 . A fixed pulley  14  is equipped at the top of the support frame  12 , also a steel wire rope  15  which one end is connected with electric hoist  13  and the other end is connected with lifting mechanism  16  is winded on the fixed pulley  14 . The lifting mechanism  16  is equipped with three rollers  17 , 2 pressure sensors  181  and a speed encoder  182 , the 3 rollers  17  are arranged in a “ ” shape, that is, three straight lines connecting the circle center points of three rollers make up of a triangle. A pressure sensor  181  and a speed encoder  182  are equipped at one side of the three rollers, at the side of the fixed pulley  14 , altimeter encoder  183 , electric hoist  13 , pressure sensor  181 , speed encoder  182  are equipped. Both the speed encoder  182  and the altimeter encoder  183  are connected with PLC by the telecommunication wires. Fix the rotation axis  21  on the ground at one side of the guide frame  1 , connecting the rotation platform  2  with the rotation axis, meantime, the rotating platform  2  will rotate about the rotation axis  21 . The upper surface of the rotation platform  2  shall be flush with the ground, the platform rail  22  is paved on the rotation platform and the railcar  3  is located on the rail  22 . Three straight lines connecting the circle center points of three rollers make up of a triangle. The characteristics of rotation platform facilitate rail platform car easy to select multi-directions and link up with workshop rails. 
     The inner module  4  is composed by at least four support plates  41  and the support rod  42  at the top section, the four support plates  41  was aligned uniformly in the ring shape. There are gaps between the adjacent support plates  41 , the gap length shall be the width of the support plate  41  of 80% to 150% (in this embodiment, 150%). Operator can get into the inner module to operate through gaps between support plates. The support rod  42  shall be fixed by the hinge at the top of the support plate  41 , each support plate  41  shall fix two support rods and the two top of the rod  42  shall be symmetrically fixed on the support plate  41  at left and right sides. The supporting plate  41  and the railcar  3  is connected by the bolt. The top of support plate  41  will lean outward. After fixing the support plate  41  and railcar  3 , the centers of gravity of four support plates should be located outside of each hinge. 
     Put a ring shaped tray  5  onto the railcar  3  and hitch it outside the inner module  4 . Lifting points which are used for lifting the tray and looped cable strands which are winded on the tray shall be set at the tray edges, and lay the water proof film cover on the surface of the tray  5 . 
     Put one end of strand  10  through the guide rollers  11  and fix it onto the inner module  4 , then drive rotation platform  2  to rotate in the direction of arrow B as shown in  FIG. 2 , which will drive the railcar  3  and inner module  4  to rotate together. Along with the rotation, the strand  10  will be winded on the inner module  4  one circle by another from the bottom end of the inner module  4  till to the top of the inner module  4 , and then wind the strand  10  from the top of the inner module  4  to the bottom. Repeat this operation until all the strands  10  wrapped into wire strands. During the upward winding procedure, the PLC will control the electric hoist  13  to pull the steel wire rope, thus to lift the lifting mechanism  16  which will enable the guide roller  11  move upward with the distance which is equivalent to the strand  10  diameter during each circle. During the downward winding procedure, the PLC will control the electric hoist  13  to pull to steel wire rope  15 , thus to pull down the lifting mechanism  16  which will enable the guide roller  11  move downward with the distance which is equivalent to the strand  10  diameter during each circle, therefore guarantee that strands are capable of arranging on the inner module  2  regularly and compactly. 
     After all the strands  10  are winded into wire strands, as shown in  FIG. 5 , dismantle the bolts between the bottom of the inner module  4  and the railcar  3 . Lift the support rod  42  on the inner module  4  in the direction of arrow C as shown in  FIG. 3  which will make the 4 pieces support plates  41  gather together inward, and then extract the inner module  4  from the wire strand. After this, use the prepared waterproof film on the tray  5  to cover the whole outside surface of the wire strand  10 . Connect the platform track  22  on the rotating platform  2  with the track on the ground, pull the railcar  3  to move the wire strand  10 , until this winding operation is finished. 
     (b) Performing the unwinding operation, the operation procedure is as follows: 
     As shown in  FIG. 6 , fix the guide frame  1  on the ground, the guide frame  1  is shown in  FIGS. 3 and 4  and composed by the base  11 , support frame  12 , electric hoist  13 , fixed pulley  14 , steel wire rope  15 , lifting mechanism  16 , roller  17 , the pressure sensor  181 , speed encoder  182 , altimeter encoder  183  and limit roller  19 . Fix the base  1  on the ground and fix the support frame  12  and electric hoist  13  on the base  1 . A fixed pulley  14  shall be equipped at the top of the support frame  12 , also the steel wire rope  15  whose one end is connected with electric hoist  13  and the other end is connected with lifting mechanism  16  shall be winded on the fixed pulley  14 . The lifting mechanism  16  is equipped with 3 rollers  17 , 2 pressure sensors  181  and a speed encoder  182 . The 3 Roller  17  is arranged in a “ ” shape, that is, three straight lines connecting the circle center points of three rollers make up of a triangle. A pressure sensor  181  and a speed encoder  182  shall be equipped at one side of the three rollers, at the side of the fixed pulley  14 , altimeter encoder ( 183 ), electric hoist  13 , pressure sensor  181 , speed encoder  182  shall be equipped. Both the speed encoder  182  and the altimeter encoder  183  shall be connected with PLC by the telecommunication wires. Fix the rotation axis  21  on the ground at one side of the guide frame  1 , connecting the rotation platform  2  with the rotation axis, meantime, the rotating platform  2  will rotate around the rotation axis  21 . The hydraulic brake  24  which is connected by pressure sensor and PLC is equipped in the rotation axis  21 . During the rotation of the rotating platform  2 , release the hydraulic brake  24 . When the rotating platform stops, the hydraulic brake  24  is always imposing friction on the rotating platform  2 , thus applying portion of reverse compression to prevent against rotating platform  2  continually rotating, bring about cable strand dropped out and injury when dragging forces temporarily stop. 
     The inner module  4  is composed by at least four support plates  41  and the support rod  42 . The number of support plate  41  in this embodiment is selected as 4. The four support plates  41  are aligned uniformly in the ring shape. The gaps shall be retained between the adjacent support plates  41 , the gap length shall be the width of the support plate  41  of 80% to 150% (in this embodiment, 150%). The bottoms of the support plates  41  are connected by the hinge with the rotating platform  2 , all the 4 pieces support plates  41  will lean inward. In the middle of the 4 pieces support plates  41 , a hydraulic jack  6  is equipped. The support rod of the hydraulic jack  6  is connected with four pieces push rods  61 , and each push rod  61  shall withstand a piece of support plate  41 . 
     Remove the waterproof film cover from the strand  10 , lift the strand  10  wire strands together with the tray  5  onto the rotating platform  2 , meantime, and set the strand  10  wire strands over the inner module  4 . Actuate the hydraulic jack  6 , with the force of the support rod applied to the push rod, the 4 pieces support plates  41  will push outward by the push rod  61  which will fix the strand wire strands. 
     Pull one leading end of the strand  10  through out of the guide roller  11 , then pull the strand  10  to drive the inner module  4  and the tray  5  to rotate, thus to drive the rotating platform  2  to rotate around the rotation axis. Along with this operation, the strand  10  shall be released and will become straight status. 
     During the downward winding procedure, the PLC will control the electric hoist  13  to pull to steel wire rope, thus to pull down the lifting mechanism  16  which will enable the guide roller  11  move downward with the distance which is equivalent to the strand  10  diameter during each circle. During the upward winding procedure, the PLC will control the electric hoist  13  to pull the steel wire rope  15 , thus to lift the lifting mechanism  16  which will enable the guide roller  11  move upward with the distance which is equivalent to the strand  10  diameter during each circle. Repeat these operations back and forth till the wire strands strand become straight status, and fulfill the whole unwinding operation. 
     Under the controlling action of the PLC, the unwinding of cable strand is restricted to prevent against out of control for strand, avoiding cable strand damage or injury or loss; in unwinding strand operation, can keep line shape relatively straight and level to protect strand and prevent binding band breakdown, when the speed of unwinding strand is slowed down or stop, gradually control hydraulic brake  24  to lock turning axle; the introduction of pressure sensor furthermore facilitate PLC to control hydraulic brake  24  smoothly. 
     Embodiment 2 
     It is a method for horizontally winding and horizontally unwinding a parallel wire strand. The method includes winding strand and unwinding strand operations. During the winding strand the container  4  is composed by 6 support plates  41  and the top support rod  42 . The six support plates  41  are aligned uniformly in the ring shape. There is a gap between the adjacent support plates  41 , and the gap length is 100 percent of the width of support plate  41 . The rest structure and method are the same to embodiment 1. 
     Embodiment 3 
     It is a method for horizontally winding and horizontally unwinding a parallel wire strand. The method includes winding strand and unwinding strand operations. During the winding strand the container  4  is composed by 10 support plates  41  and the top support rod  42 . The ten support plates  41  are aligned uniformly in the ring shape. There is a gap between the adjacent support plates  41 , and the gap length is 80 percent of the width of support plate  41 . The rest structure and method are the same to embodiment 1.