Mold parts Force plug

Cavity retainer plates are plates in a mold that hold the cavities and plugs. These plates are at the mold parting line and usually contain the guide pins and bushings. They are also called force retainer plates. See Fig. 1.4.)... 

Figure S.7 Cross section of a split cavity mold for producing a molded spool. A and B form the two halves of the cavity. Chase, C, folds the halves together. Other parts are D, core pin E bottom plate and F, the force plug or plunger. (Ref Buckleitner, E.V., ed., Basic Mold Types and Features , Plastics Mold Engineering Handbook, S " ed.. Chapman Hall, New YotIc)...

Plunger plon-jori n (1611) The part of a transfer-press or old-style injection machine that applies pressure on the unmelted plastic material to push it into the chamber, which in turn displaces the plastic melt in front of it, forcing it through the nozzle and into the mold. See also Ram, Force Plug, and Pot Plunger. 

A small amount of particleboard is made with a fire-retardant treatment for use in locations where codes require this material, as in some offices and elevators. Particleboards receive overlay and finishing treatments with ease. Wood veneers, melamine overlays, printed paper overlays, vinyl overlays, foils, and direct grain printing can all be done quite simply. A small amount of particleboard is also made in the form of shaped, molded articles such as furniture parts, paper roU plugs, bmsh bases, and even toilet seats. There is another small increment of particleboard made by the extmsion process. These products are made in small captive operations owned by furniture manufacturers which consume all of this production in their furniture. The extmsion process differs from conventional flat-pressed particleboard in that the wood furnish is forced between two stationary heated surfaces. The mats are formed from one edge and this edge is alternately formed and pushed between the heated platens, which are maintained at a distance equal to the thickness of board produced. This is an old, slow, small-scale process, but is stiU in use in at least one location. 

The plug is forced into the cavity and the product is cured. The plunger is somewhat deeper and narrower than the cavity. It is tapered in such a manner that contact occurs first in the lowest part of the mold. 

The plug is forced into the cavity and the product is cured. The plunger is somewhat deeper and narrower than the cavity. It is tapered in such a manner that contact occurs first in the lowest part of the mold. Ultimate pressure usually used are up to 400 to 700 kPa (58 to 100 psi) in the plimger causes the contact area to expand radially toward the rim of the cavity, thereby forcing the resin and air ahead of it through the reinforcement wdth the target of developing a void free product. 

The die block is the part in an extrusion die that retains the forming bushing and core. In an injection mold, it is the part that contains the cavity or plug (force). The die adaptor is the part of an extrusion die that holds the die block. 

The majority of thin-gauge parts are formed into female or negative cavities. For deep cavities or multiple-compartmented cavities, mechanical assists, called plugs, are used to prestretch the sheet before vacuum and/or pressure is used to force the sheet against the mold surface. Air pressure to 5 bar is used, in conjunction with vacuum, for deeply drawn parts or for parts requiring high surface detail or sharp radii. 

There are a number of variations on the basic process, which are described in more detail by Throne (1986). For example, in plug-assisted vacuum forming the heated sheet is forced by a plug into the mold with the remainder of the shape being produced by the application of vacuum to the underside of the sheet. This method is used to help maintain a more uniform wall thickness throughout the part. Another example is matched die molding, which is shown in Figure 10.13. 

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