hot runner technology|hot runner system technology
With the widely use of hot runner system,hot runner technology has been more mature and optimizes day by day.It has reached the achievement of high technology application,advanced injection molding technology,also high hot runner technology production.
Compares the hot runner mold with the ordinary runner mold , it has the advantage of high injection molding efficiency,good quality of formation models, and saves merits raw material and so on. Along with the polymer industry's development, the hot runner technology is developing consummates unceasingly, its application scope is also getting more and more widespread. The hot frunner is through the heating means guaranteed that the runner and the runner plastic maintains the molten state. Because it is equipped with stick and the heating coil nearby the runner or the center ,it keeps high temperature from the sprue of injection machine to the nozzle,keeps the plastic in molten state.after the engine off,needn't to open the runner to take out the congeals material, only need to heat up the runner to its necessary temperature when starting again.The hot runner injection molding methods was appeared in the 1950s, after having experienced a period of long time promotion, its market share rises year by year , in the mid-80s, US's hot runner mold accounted for the injection mold total 15%~17%, Europe was 12%~15%, Japan was 10% approximately . But to the 90s, in the plastic injection mold which the US has produced the hot runner mold accounted for above 40%, accounts for above 90% in massive article's injection mold. The hot runnerl system's superiorities are saves raw material, to reduce the product cost is the hot frunner mold most remarkable characteristic. In the ordinary gating system must produce the massive material handle, when produces the small product, the gating system congeals the material weight possibly to surpass the product weight. Because the plastic has been at the molten state in the hot runner mold, the product cannot prune the runner, basically is the non-waste material processing, therefore may save the massive raw materials. Because it does not need working procedures and so on. waste material recycling, choice, smashing, dyeing, therefore the labor saving, time-saving, the energy conservation falls consumes. , because the runner material which no longer mixes in passes through processes repeatedly, therefore the product quality obviously enhances.
because the gating system plastic maintains fusing simultaneously, the pressure loss is small when flowing, thus easy to realize the multi-runners, polymorphism cavity die to have and the massive article low pressure injection. The hot runner favors the pressure transmission, to a certain extent can overcome models as a result to make up hollowly, flaws , shrink hole , distortion and the material insufficient forms. resin applicable scope is broad , the formation hypothesis condition is convenient. Because the hot runner system technology warm consummation and development, now the hot runner not only use in fusing the temperature wide polyethylene, the polypropylene, can also use in the processing heat-sensitivity plastic which temperature scope narrow, like polyvinyl-chloride, metaformaldehyde (POM) and so on. To easy to produce salivates gathers amide (PA), through selects hot runner nozzle valve type also to be able to realize the hot runner formation. Moreover, the operation simplifies, the reduction formation cycle is also a important characteristic of hot runner mold's . Compared with the ordinary runner, reduces molds opened the matched schedule, not only reduced workpiece's drawing of patterns and the formation cycle , moreover advantageous in realizing the automated production. Statistics indicated that compares with the ordinary runnerl, after changing to the hot runner formation cycle to be possible to reduce 30% generally.
With the fasten development of mould technology,hot runner technology also along with consummation.