Into rotary molds

Lecithin will function as a release agent, providing cleaner and faster pet food or biscuit parting from a stamp or mold. A reduction in the amount of pressure required to create an impression with a stamp is seen when lecithin is used in the mix. The ease of formation of intricate, stamped, surface appearance details, especially with low-fat products, is also improved with lecithins. When dough is being cut, lecithin improves release from the die, especially with rotary cutters. With superior release, foods and biscuits are formed with a better impression, and lower numbers of cripples (i.e., improperly formed product). Some pet biscuits are formed from a batter injected into a mold prior to cooking. Lecithin can improve flowability of the batter so that it fills all the mold corners and cavities. After cooking, lecithin improves release from the mold. 

Two types of preplasticizer machines are shown in Figs. 4-2 and 4-3. The two-stage plunger system shown in Fig. 4-3 is similar to the single plunger system except the melt is forced into a second chamber instead of the mold. The melt is then forced into the mold by the second plunger. The direction of melt flow is controlled by a 3-way rotary valve. 

Shutoff nozzles are used to prevent nozzles from leaking into empty molds or when the nozzle is retracted from the sprue bushings. Valves of all kinds —i.e., spring-loaded ball check valves, hydraulically and mechanically operated needle valves, and rotary valves —have been incorporated into nozzles. 

Conventional extmsion or coextrusion may be performed on vertical or horizontal rotary or shuttle mold configurations. In shuttie blow mol ding the extmder and die are in fixed horizontal and vertical position two or more molds shuttie into and out of position beneath the die. By reciprocating in two planes, the mold may remove a parison and permit the extmder to function continuously. 

Horizontal rotary machines employ multiple molds in a horizontal plane on a rotary turret. As each mold approaches the extmder die exit, it opens to accept the parison and then closes. The parison is then blown into the bottle shape. The extmder must extmde on an intermittent basis or be intermittently withdrawn to provide a parison for each passing mold. 

Add wood furnish (384 g, moisture content 6.02%) to the bowl of a rotary blade paddle mixer (such as a Kitchen-Aid KSM90) and agitate at the lowest speed setting. Add Mondur 541 (7.39 g, 1.9% w/w, a polymeric diphenylmethane diisocyanate of 31.5% NCO, Bayer) dropwise over a 5-min period using a disposable syringe. Continue blending for an additional 10 min and then transfer the blend to an 8 x 8 x 2 -in. metal form at the bottom of which is a metal plate which fits inside. The resin-coated furnish is evenly spread inside the form and another metal plate is placed on top. All parts of the form and plates are presprayed with mold release. The completed form assembly is placed into a hydraulic press (such as a model PW-22 manufactured by Pasadena Hydraulics) with platens heated at 350°F. The furnish is then pressed between the two form plates to a thickness of j in. Press controls are used to ensure consistency of board thickness. The assembly is heated for 4 min. before demolding the cured wood panel. 

A sample of monomer ( 50 g) was placed in a 100-ml round bottomed flask, which was attached to a rotary evaporator. The flask was heated to 150°C with the aid of an oil bath while stirring under vacuum (0.20 mmHg). The monomer was stirred and heated under vacuum for a period of 45 min to 1 h in order to simultaneously degas and B-stage the monomer. The B-staged monomer was then held under nitrogen and poured into a preheated mold, which consisted of two polished aluminum plates (6 x 6 x 1/2 in.) with a three-sided 1/8-in. thick Teflon spacer between the two plates. The spacer was cut from a 6 x 6 x 1/8 in. 

To increase the production rate, the casting devices and the molds are grouped into one unit. Linear, vertical rotary, and multi-layer units are the most common.171... 

Borax is also manufactured from calcium borates by heating with a sodium carbonate/sodium hydrogen carbonate/sodium hydroxide solution, whereupon the calcium carbonate precipitates out and sodium borate crystallizes out. Anhydrous borax is formed by calcining water-containing sodium borates initially in rotary tube furnaces, then in standing furnaces, it being produced as a liquid which is poured e.g. into molds. 

There are several different IBM methods available, with different means of transporting the core rods from one station to another. These methods include the shuttle, two-parison rotary, axial movement, and rotary with three or more stations used in conventional IM clamping units. A variation of IBM is displacement BM or dip molding. A premeasured amount of hot melt is deposited into a cupel, the shape of a preform. A core rod is inserted... 

Coinjection basically means that two or more different plastics are laminated together. These plastics could be the same except for color. When different plastics are used, they must be compatible in that they provide proper adhesion (if required), melt at approximately the same temperature, and so on (see Table 7-9). Two or more injection units are required, with each material having its own injection unit. The materials can be injected into specially designed molds— rotary, shuttle table, and the like [12]. 

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