Wheel machines

Extrusion blow moulding (the simplest), in which the parison is an extruded tube that is blown with air. Various types of machinery are marketed shuttle, reciprocating and wheel machines. 

Figure 6,8 Schematics of vertical wheel machine in a production line (courtesy of Graham Machinery Group)...

The third and most successful approach was accomplished on a wheel-type blow molding machine. Unlike the shuttle machine where only gravity acts on a downward extruded parison, a wheel machine draws or pulls the parison from the die. This allows extension in the extrusion direction and the opportunity to thin down the barrier layer and reorient the mica platelets. 

Experimental bottle made with ketchup-style mold on wheel machine... 

Coex Blow Molding Barrier okay from wheel machine Color may be unacceptable... 

Spur, G., Stark, C., and Tio, T.H., 1985, Grinding of non-oxide ceramics using diamond grinding wheels. Machining of Ceramic Materials and Components, Sub-ramanian, K. and Komanduri, R., Eds., PED-Vol. 17, ASME, p. 33. 

Fig. 16. Schematic of a rotary or wheel machine with continuous extrusion of the parison. Number of blow molds depends on size of wheel diameter and extruder size for output.

Wheel machines are designed specifically for dedicated products, such as picnic plates, dual-ovenable food trays, and takeaway coffee lids [8]. The wheel is a horizontal cylinder that contains dozens to hundreds of female or negative molds. The sheet is continuously extruded through the sheet die directly onto the slowly turning wheel. Vacuum pulls the sheet into the cool molds. As the wheel turns, the formed products are cooled. When the products are sufficiently cooled, the sheet containing the products is stripped from the wheel and fed to a conventional in-hne trimmer. 

Relative movement between the parison head and mold is necessary so that parison extrusion can proceed continuously while the mold is closed. This is achieved in many different ways. The mold may be lowered, moved aside laterally, or swung aside on an accurate path. Alternatively, the extruder may be moved while the mold remains stationary. Often, two molds are used in a shuttle arrangement, so that one is open for parison extrusion while the other is performing the blowing cycle. One method of mold movement results in very high production rates. In such machines, generally known as wheel machines, a number of molds are mounted on a rotary table. Movement of the table carries the closed mold away and presents a new open mold to the die head, allowing extrusion to continue. 

You can see quite clearly that it is not the pressure of the steam that is driving a turbine. Place a pressure gauge on the turbine case of a single-wheel machine. The pressure on the turbine case will be quite close to the exhaust steam pressure and certainly not the motive steam pressure. 

Figure 11.3 shows the arrangement used for crystal slicing. A carborandum powder in glycol slurry is fed over the spring steel blades and the crystal is moved reciprocally over the blades to abrade the crystal to produce shces of 0.35-0.5 mm thickness. Diamond sHcing, on a similar machine, on a peripheral-wheel machine and on single- and multiwire machines has also been tried but problems with... 

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