There are various reasons for choosing RIM molding for your attachment, housing, enclosure, and structural areas. Some of these relate to the components made using plastic reaction injection molding (RIM). The factors listed below aides and incorporate function into the part: deep draws, large components, numerous wall sections contained in the same part, insert molding and assembly and low annual rate of production.
What is RIM?
Reaction Injection Molding (RIM) was invented in Europe by Bayer AG in around 1960s period and it was utilized as a viable option to thermoplastic injection molding. Rather than of utilizing melted plastic pellets being forced into a steel mold under the influence of extreme temperature and pressure, RIM is made up of low viscosity liquids, an isocyanate, and a polyol. These liquids are mixed together and passed into a lightweight aluminum or epoxy mold under the influence of low pressure and temperature. In the mold, the liquids will have to pass through an exothermic (heat producing) chemical reaction and must also undergo polymerization reaction to form polyurethane.
As a result of the low viscosity of the reactant liquids (500-1500 centipoise) and the system low-temperature range (90˚-105˚ F), there is every chance that a normal mold can fill in within moments, even under molding pressures of about 50-150psi, and the finished component can be deformed within a short period (30-60secs). By selecting various formulations of resins, the polyurethane produced can undergo some optimizations for durability, flexibility, surface toughness, wear resistance, elasticity, reduction in sound/vibration effect, dimensional firmness, reduction in the effect of heat, and electrical, chemical, or fire resistance.
For numerous years, there has been a massive increase in the use of Reaction Injection Molding all over the globe especially in Europe and in most of the American automotive companies (where they use it for the production of both internal and external body components). Also, due to the fact that many industrial manufacturers located in the U.S have discovered the benefits of RIM and the design freedom it allows other industries like medical devices and electronic enclosures have started to utilize it.