3000cc Horizontal Rubber Injection Molding Machine / Polymer Line Insulator Molding Machine for Tansmission Line

          300ton Force Horizontal Polymer Line Insulator Molding Machine for Tansmission Line
 
 
Detail Theory for transmission Line Insulator :

• The most critical thing to be considered in outdoor insulators is the interface between the solid insulting body and the surrounding air. The problem appears at the interface because it is the interfering point of air and the solid insulator. This problem arises due to the effects of pollution, rain, dust, salt, corona, arcing over surfaces, nitric acid in air, etc. These things increase the leakage current and deteriorate its performance. Surfaces of insulating bodies were therefore coated with glazed material for glass and porcelain insulators, and organic or semi-organic polymer rubbers for composite insulators. A typical composite insulator is composed of a glass fiber reinforced (GFR) epoxy or polyester core (rod), attached with metal end-fittings. (GFR) This is the load bearing structure. GFR plastics are mechanically very strong but are not able to bear the outdoor environmental effects.  
• The presence of dirt and moisture in combination with electrical stress causes the material to degrade by tracking and erosion. So the rod is covered by a coating that protects it from outside stresses such as rain, salt, fog, pollution, etc. This coating is referred to as housing. A housing material should be able to protect the load-bearing core and provide sufficient pollution withstand. The reason of use of rubbers instead of ordinary plastics is simply the fact that the housing must be flexible enough to follow the changes in dimension caused by temperature or mechanical load. 

Molding Techniques of Transmission Line Insulators:

• Experience of outdoor insulation started from the introduction of telegraphic lines. The pin and cap type insulators have been used since the last quarter of the 18th century. These insulators are very reliable. Glass and porcelain insulators were the only type available before the introduction of newer polymeric insulators and thus had fully ruled over the market till late second half of the 20 th century. The polymeric insulator has a fiber rod structure covered with weather resistant rubbers and fillers and fitted with end fittings. Such a type of insulator is also called composite insulator.

• The whole insulator housing is then injection molded directly around the core in one piece.  In this way, the housing can be chemically bonded to the core, and the number of interfaces where moisture can penetrate is minimized. This technique is the most attractive to manufacturers because of the lower number of steps involved and short time of processing. There are three main types of silicone rubbers used in high voltage insulation applications: high temperature vulcanizing (HTV) silicon rubber, room temperature vulcanizing (RTV) silicone rubber and liquid silicone rubber (LSR). HTV is cured at high temperature and pressure, catalyzed by peroxide induced free radicals or by hydrosilylation catalyzed by a noble metal, ie platinum. HTV RTV is cured at lower temperature, ie around room temperature, by condensation reaction as one component system.