Introduction 253 vacuum pump resin supply mould cavity vacuum gauge pressure gauge peristaltic pump FIGURE 7.5(a)Vacuum-assisted molding arrangement. pressure,more voids may appear in the part.Figure 7.5 shows schematics of the VARTM. Seaman composite resin infusion molding process (SCRIMP): This process is similar to VARTM in which only vacuum is used to provide the pressure gradient.In the case of RTM,both mold surfaces are hard,meaning both mold surfaces are made of some sort of metal.In the case of SCRIMP,only one mold surface is hard,the other mold surface is a flexible membrane that is used to contain the vacuum.Figure 7.6 shows a schematic of the process. In SCRIMP,the liquid resin flows in between the flexible membrane and the fiber preform.This type of flow is rapid since Cover strip to prevent the vacuum gallery Clamp Resin in from becoming blocked Seal strip Vacuum out Lower tool face FIGURE 7.5(b)Cross section of a VARTM set up.pressure, more voids may appear in the part. Figure 7.5 shows schematics of the VARTM. • Seaman composite resin infusion molding process (SCRIMP): This process is similar to VARTM in which only vacuum is used to provide the pressure gradient. In the case of RTM, both mold surfaces are hard, meaning both mold surfaces are made of some sort of metal. In the case of SCRIMP, only one mold surface is hard, the other mold surface is a flexible membrane that is used to contain the vacuum. Figure 7.6 shows a schematic of the process. In SCRIMP, the liquid resin flows in between the flexible membrane and the fiber preform. This type of flow is rapid since Introduction 253 FIGURE 7.5(b) Cross section of a VARTM set up. FIGURE 7.5(a) Vacuum-assisted molding arrangement