Present. Hose with reinforcing material from the cotton fiber turned to chemical fiber, in which PVA fibers with good physical properties and mature processing technology has been favored hose manufacturers, but their prices are rising. Suction hose on the farm had a greater impact.To reduce costs, the need to use cheaper materials skeleton. Tubes used in the Jiao Jiao stick, cotton, polyvinyl alcohol, polyester and glass fiber reinforcing materials, only the glass fiber is relatively inexpensive, but its elongation is small, poor bending properties. Difficult to promote the use of the price of polypropylene canvas and glass fiber cloth is similar to the advantage of physical properties of density, high strength, bending performance, process operation is simple and disadvantages of the low adhesion, heat resistance is not good, so that it can be a significant deformation suction hose application. We have taken a lot of solutions.
l. polypropylene canvas with rubber to improve adhesion of the impregnated polyester or polyvinyl alcohol solution to impregnated polypropylene fabric to improve the impregnation technology, cloth Count Gaixiao. Due to increase yarn roughness, improved rubber formulations, so that polypropylene cloth and rubber adhesive force increased to meet the use requirements.
2. does not improve the thermal stability of polypropylene fiber polypropylene canvas at 00C when the shrinkage. 5, in the] 30c when the shrinkage rate of 5 O, at room temperature, elongation at break of 2O -80, and therefore in the processing of dimensions is often unstable, causing difficulties to the process. In order to overcome this weakness, increase the width of the canvas. In Soaking time (no more than] 40 () let the natural shrinkage. And then cold shape and tension, thus avoiding the process of transverse shrinkage in the calendar too much problem.
3.to take appropriate after the calendering process impregnated polypropylene fabric surface still smooth, easy rolling when the plastic cover. If the plastic cover a small amount of power affected the adhesive sets, so we adjusted accordingly, and rubber formulations. And took the following measures:
(1) without drying and heating, direct rolling eraser (:) will be rubber-plastic values to more than 0.55.
(3) calendar using high-speed ratio (1:1 _4: 1) to increase the amount of plastic cover.
(4) The roller temperature requirements: on the roller (95 = 5) C; the roller (80 soil 5) C; under the roller (70 ± 5) C
(5) The amount of rubber containing rubber requirements for 3o a 35 and use 10 silica.
4. to improve molding and vulcanization process despite pre-treatment, rolling polypropylene tape still exists after the soft cloth, very poor, resulting in heat shrink and other problems, which can only be hand-cutting, molding shop light when light pull, with plastic of force at both ends wrapped around the tube well to prevent them from heat shrink. Curing pressure control for the 0.3 0 35MPa. After vulcanization. Use cold water to cool off and then die, so. De-core convenience, possession of body is not shortened.
5 finished product testing and cost-effective sampling a 7 6_2mm (3 Yingcun) × 9m of the hose. Conducted a vacuum test tube without suction bian and the delamination phenomena. Pressure test to 0.5MPa, the non-leakage. Physical performance test results of finished product: cloth and fabric adhesive strength 2.29kN · IT'-1, glue and fabric adhesive strength 2.34kN · m a hose does not occur after two years of the use of quality problems. The use of polypropylene canvas has obvious economic benefits, per meter compared with the same strong polypropylene canvas cloth PVA 1 yuan cheaper, and glass fiber cloth prices are pretty.
| Add time：2010-01-25 17:18:07 Click on the number：2231 source：连达网
|
