Resin transfer moulding manufacturing

Scott FN, Heath R. Resin transfer moulding for civil aircraft manufacture. SAMPE European Chapter 1992. pp. 235—47. 

Bickerton S, Kelly P. Compression resin transfer moulding (CRTM) in polymer matrix composites. In Advani S, Hsiao K-T, editors. Manufacturing techniques for polymer matrix composites (PMCs). Cambridge (UK) Woodhead Publishing Limited 2012. 

Manufacturing methods for composites vary from manual to fully automated processes, whereby the latter have better quality control than the former. Wet layup, pultrusion, and filament winding are all discussed in some detail, while other techniques such as pull-winding, resin transfer moulding, vacuum bag moulding, and injection moulding are left to specialized composite materials texts. 

Source Reprinted with permission from Abraham D, McCarthy R, Design of polymer composite stmclural components for manufacture by resin transfer moulding (RTM), SAMPE Europe Conference and Exhibition. Proc of 2Cf International SAMPE Europe Conference of the Society for the Advancement of Materials, Paris, France, 407-415, 1999. Copyright 1999, The Society for the Advancement of Material and Process Engineering (SAMPE). 

Natural fibre composites are prepared using various composites manufacturing methods such as compression moulding, injection moulding, Resin transfer moulding (RTM) and vacuum bagging. The preforms are mostly fibres, fabrics or non-... 

In resin transfer moulding, the resin is injected into a mould containing layers of fibres or a preform at low pressure. The process cycle time is less than 3 minutes, and the fibre content of the composite product is up to 50%. The advantages of the process are design flexibility, ability to manufacture larger structures, low cost (thanks to the low pressures involved) and rapid manufacture. As with sheet moulding, resin transfer moulding is widely used in the automotive industry to manufacture a variety of parts for cars and other vehicles. 

Akbar S. Numerical simulation of three-dimensional flow and analysis of filling process in compression resin transfer moulding. Composites Part A Applied Science and Manufacturing, 2006 37(9) 1434—1450. DOl 10.1016/j. composi tesa.2005.06.021. 

Bechly ME, Clausen PD, Snaith H. Structural Design, Manufacture, and Testing of Resin Transfer Moulded Blades for Small Wind Turbines. Bury St Edmunds, UK Mechanical Engineering Publications, 1997. ISBN 1-86058-034-3. 

A low temperature latent acid hardener (RC-901A) curing, phenolic resole suitable for resin transfer moulding, filament winding, hand-lay, pultrusion and in the manufacture of syntactic foams. 

Manufacture was achieved by resin transfer moulding using cold cure catalyst. 

The clamp is manufactured via Vacuum Bag Resin Infusion, a process that is similar to Vacuum Assisted Resin Transfer Moulding, at room temperature. Machining and drilling are required to form the necessary grooves that house the seals and the holes for the fasteners, respectively. Alternative manufacturing approaches may be used, such as wet lay-up and resin transfer moulding. A typical ProAssure Clamp is shown in Figure 12.2. 

Closed mould (or matched-die moulding) processes are used in the composites industry for fabrication and manufacturing of three dimensional compounds and products. There are different closed moulding processes. Within these, there are transfer moulding, compression moulding, resin injection moulding, injection moulding, pultrusion and extrusion. 

Bulk applications of PF resins utilize novolaks in formulations designed for rapid cure. Traditionally, components were manufactured by compression or transfer moulding, the latter being preferred for products with moulded-in inserts. Injection moulding is gaining in use, for example for electrical components, electric iron handles (see Chapter 9), or saucepan handles (see below). 

Transfer molding is used for the manufacture of small components and is particularly useful with multi-cavity tools and where small inserts are to be moulded in. Materials used are polyester and epoxide dough moulding compounds, although a new liquid resin injection technique is reported. 

---