Low pressure perfusion equipment

    Rapid tooling technology is accompanied by rapid prototyping technologies in the development of a new technology. rapid tooling and low-pressure perfusion molding refers to the high chemical activity, low relative molecular mass of the double group component material after mixing in a certain proportion, at low pressure (0.4 ~ 0.5mpa) under the mold injection airtight, complete polymerization, crosslinking, curing chemical reaction, and by cooling curing, eventually forming process of products, low pressure perfusion molding (rim) technology in the developments in the field of rapid tooling molding products. products material general for polyurethane resin, after forming a thermosetting materials of nature-the quality of its products filling process, mold with mold structure, temperature, initial temperature of raw material, material mixing ratio and mixed degree, which is closely related to the curing time.

    Rapid tooling and low-pressure perfusion molding refers to the polyurethane resin injected into rapid tooling and molding curing process. you can use silicone mold mold mold mold, epoxy resin, polyurethane, abs and aluminum mold. low perfusion molding equipment mainly by control box, dosing pumps, mixing head and nozzle etc. the technological process is shown in figure 1. low perfusion molding equipment in 0.4 ~ for low pressure 0.5mpa bicomponent polyurethane materials under the quantitative pump into the mixing head, upon impact after mixing and then injected into the mould. after mixing of the two component material within the mold rapid reaction, polymerized with crosslinking curing. in order to ensure the material fully cured, reduce the deformation of products, generally after the completion of the injection, mould needs to be moved taking place within the oven after curing, about 1.5 ~ after 2.0 hours of release by products. usually a pair of mold production cycle for 3 ~ for 4 days, for production of 100 ~ about 500 pieces of products. in accordance with the technical requirements, before the injection moulds and materials shall be heated. as a result of two component curing reaction of materials, in the initial stage of forming process, the whole reaction system the temperature will rise still further, the emergence of exothermic phenomenon.

    Low-pressure perfusion molding material mainly used in polyurethane material for the lord. to change the mix of materials, available in different material of elastic modulus, and thus receive the needed materials characteristics of! after curing material physical properties similar to those of ordinary thermoplastic material abs, PP or PS. suitable for larger wall thickness (> 4mm) and uneven wall thickness of products production.
Rapid tooling and low-pressure perfusion molding with technological characteristics are as follows:
    ① the perfusion pressure molding process molding curing, the heat exchange process of both physical, and chemical polymerization, crosslinking process, its process is not only affected by the reaction kinetics and thermodynamics of the decision, are also physical conditions of impact;
    ② material curing time longer, and curing and cooling of the material in the briquetting process takes up the vast part of the time;
    ③ after forming of materials with thermosetting materials of nature;
    ④ material injection with low voltage under, therefore applies only to the structure is more simple shape of the workpiece, especially is the height size is much smaller than the length and width dimensions of simple molding shell shape of workpiece.