Steel cord conveyer belt _vulcanization joint structure.
The joint strength retention rate, the average effective distance and the length of the joint are directly affected by the structure of the joint. The choice of the joint should be based on the full consideration of the center distance of the wire rope diameter and the wire rope. Joint structure belt from ST630 mainly adopts strong overlap and dislocation lap conveying port of Huanghua wire rope core, more commonly used one order and two order method of lap lap joint method, the joint size and lap mode selection (Figure 1, 2) as shown in.
The analysis of the joint structure shows that the strength is related to the following factors: the characteristics of rubber and steel wire rope. Center rubber gap. The joint center rubber and the gap are the main factors which influence the strength of the joints, which are subjected to axial shear, torsion and tension. Joint order. The number of higher order is conducive to improve the flexibility, reduce the rope density, effectively enlarge the contact area of rubber and steel wire rope. The form of joint. The joint order is different, the role of the rubber and wire rope tension is also different. The length of joint. Through a pull-out stress transfer block in wire rope, the joint length depends on the length of order, and order the length according to the diameter of wire rope, structure, order, order form, lap rubber properties and practical experience to determine.
3. vulcanization process
The belt joint uses 2 kinds of rubber materials, covering rubber and core adhesive, covering with high strength, abrasion resistance and impact resistance. The core adhesive has good adhesion to the steel wire rope, and ensures the drawing strength of the wire rope. According to the parameter selection of rubber tape, sulphurating should be prepared before glue and glue and a variety of equipment, tools, equipment and inspection of sulfide workplace environmental conditions. The key points of curing process are as follows:
1. To select the drying, breeze and dust free place to carry out the work. The marking after stripping wire rope, wire rope should be uniform after stripping retained 0.5mm thick transition layer core plastic, which is then polished to a rough surface using emery cloth, to increase the contact area. The use of 120# gasoline will rope clean, dry brushing glue two times, the first dry and then brush second times, again after drying on. The two sides of the joint tape each draw the center line of 1 meters long, sulfur chemical holding cord straightened, on both sides of the center line and line for complete overlap completely, then the belt fixed. The wire rope on both sides of the center line of the corresponding tape out, straighten the joint (don’t close to the interval 1mm) pressed on the lower cover rubber, wire rope are placed on both sides. Each tie 6 – 5 wire rope, to confirm that the wire rope has been attached to the center line in parallel and in a straight state, until all the steel wire rope placed. The wire rope lap gap transition region is bigger, need to put the core strip, covered with plastic cover by hammer compaction or trampling the exhaust air, the use of wallpaper knife made bleed slot is easy to exhaust. The curing temperature is controlled at 145 – 5 DEG C, curing pressure 1 ~ 1.5MPa, the curing time from when the temperature reached 145 degrees 40 ~ 50 min is appropriate, for the pressure and temperature was observed by using pressure gauge and thermometer vulcanization process.