Vacuum Infusion Process for FRP Products

 

Principle of Vacuum Infusion Process

 

Vacuum Infusion Process (VIP) uses a single-sided mold (usually hand-layup and injection mold) to establish a closed system. Simply put, the mold is covered with reinforcing materials, then a vacuum bag is laid, and the air in the system is extracted to form a negative pressure in the mold cavity.

 

The pressure generated by the vacuum is used to introduce the unsaturated polyester resin into the fiber stack through the pre-laid pipeline, so that the resin infiltrates the reinforcing material and finally fills the entire mold. After the product is cured, the vacuum bag material is removed and the desired product is obtained from the mold.

 

Principle Diagram Of Vacuum Infusion Process:

 

Driving Force: Use vacuum negative pressure to drive the resin to infiltrate and flow in the fiber.

 

 

Theoretical support for vacuum infusion molding process – Darcy’s law

 

The Essence Of Vacuum Infusion Molding Process is the process of long-range resin infiltration into porous media, and the resin flow follows Darcy’s law.

 

 

Therefore, the appropriate material can be selected through formula calculation, and the resin infusion time can be controlled by controlling the vacuum pressure.

 

Raw Materials for Vacuum Infusion Process

 

Main Materials Commonly Used in Vacuum Infusion Molding Process

 

 

Commonly Used Auxiliary Materials in Vacuum Infusion Process

 

 

Vacuum Infusion Process and Application

 

Specific Process of Vacuum Infusion Process

① Mold Preparation

② Apply Release Agent

③ Apply Gel Coat

④ Laying of Reinforcement Material and Sandwich Material

⑤ Laying of Release Cloth and Guide Net

⑥ Laying of Glue Inlet Pipeline: The Laying Principle of Glue Inlet Pipeline is to Minimize the Resin Infusion Time While Ensuring that there is no Encirclement

⑦ Arrangement of Exhaust Pipeline

⑧ Construction of Vacuum System

⑨ Leak Detection and Pressure Maintenance

⑩ Resin Infusion and Curing

 

 

Application Fields Of Vacuum Infusion Technology

Boat Industry – hull, deck, rudder, radar shield…

Wind Power Energy – blades, engine cover…

Automobile Industry – various roofs, windshields, carriages…

Sports and Leisure – helmets, windsurfing…

Construction Field – building top parts, building formwork…

Agriculture and Horticulture – granary dome, agricultural machinery protection cover…

 

Core Material Laying

 

Lay Release Cloth and Guide Net

 

Laying of Diversion Pipes

 

Laying Vacuum Bag Film

 

Import Resin

 

Vacuum Infusion Resin

 

The vacuum infusion resins, which are characterized by stable heat release, fast post-curing, small shrinkage, high strength, heat and water resistance, excellent mechanical properties, good glass fiber wettability, excellent injection performance, and can be molded into thicker products in one go. Suitable for FRP products with RTM/Vacuum Infusion Processes.

 

 

In view of the differences in product size, thickness, operation process, temperature, etc. for vacuum infusion process, appropriate gelation time and exothermic peak should be selected to meet the process requirements. If necessary, production can be specified according to indicators.