Contact molding

Glass reinforced fiber in woven, continuous and chopped roving, mat and cloth forms. Can use pre-impregnated sheets of uncured resin and fiber, called SMC. Thermosetting liquid resin commonly catalyzed polyester or epoxy. 

Production rates low. Long curing cycle typically. 

Lead times usually short, depending on size and material used for the mold. 

Multiple molds incorporating heating elements should be used for higher production rates. Material utilization moderate. Scrap material cannot be recycled. 

Direct labor costs high. Can be very labor intensive, but not skilled. 

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Contact molding Process whereby layers of resin-impregnated fabrics are built up one layer at a time onto the mold surface forming the product. Little or no pressure is required for laminate curing. 

Contact molding Also called open molding or contact pressure molding. It is a process for molding RPs in which the reinforcement and plastic are placed in a mold cavity. Cure is either at room temperature using a catalyst-promoter system or by heating... 

Part Design Blow Molding Casting Compression Extrusion Filament Winding Injection Matched Die Molding Rotational Thermo- forming Transfer Compression Wet lay-up (Contact Molding)... 

Contact Molding. Spray-up Pressure Bag Filament Winding Continuous Pultrusion Premix/ Molding Compound Matched Die Molding with Preform or Mat... 

Polymethylphenylsiloxanes with active hydrogen atoms and vinyl groups at the silicon atom are used to manufacture glass fibres (by the contact molding technique), glue compositions and filling compounds. 

Standard specification for contact-molded FRP chemical-resistant tanks Standard specification for PTFE PFA FEP- and ETFE-lined piping Standard specification for PE and polypropylene (PP) plastic-lined ferrous metal pipe and fittings... 

Hand Lay-Up (Contact Molding). A layer of liquid resin is applied to the surface of the mold. A layer of glass fiber mat (low strength) or fabric (high strength) is hand laid over it. Liquid resin is poured over it, and brushed or rolled (squeegeed) into it. The process is repeated to build up the desired thickness of the product. The assembly is allowed to stand until cured. 

Bag Molding Hinterspritzen Contact Molding Filament Winding Fabricating RP Tank... 

Pari design Casting Compression Filament winding Injection Matched die molding Rotational Transfer compression Wet lay-up (contact molding)... 

Unsaturated polyester resins are one of the most important thermosetting resins used for preparing molding compounds for hot-press matched molding, cold molding, eind contact molding. 

Custom Contact Molded Reinforced Polyester Chemical Resistant Process Equipment (PS15-69), a Department of Commerce Standard 15 years old, but still containing much useful information on materials and the manufacture of tanks, ducts and pipes. 

Contact Molded Glass Fiber Reinforced Thermoset Resin Chemical Resistant Tanks (ASTM D-4097-82)... 

In contact molding, the block, say 2" thick, can be attached to the inner mold, and joints between the blocks made with an elastomeric adhesive, and then the FRP laid up upon, and bonded to, the back of the block. Now when the molds are stripped, the liquid contact face will be the borosilicate block, which has a top surface operating temperature of 960°F. In these higher thermal ranges, the coefficient of thermal conductivity of the block ranges from 0.60 to 0.75. Thus, it is possible to operate a vessel so lined at, say, 600°F, while keeping the inner surface of the FRP unit at about 320°F. For greater thermal drop (cooler FRP), a thicker layer of block would be used. 

Eining for the heads are thermoformed afterpieces are welded. Carbon cloth is first laid using the resin. FRP is then laminated by contact molding (hand layup). The edge of the liner is left uncovered for subsequent welding. 

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