Specialty machines

There are many different equipment options avaQable to suit specific product needs including continuous winders for pipe, multiaxis winders for pressure vessels, and simple lathe-type winders for tanks and large pipe. Specialty machines combine a chopped reinforcement with continuous fibers for tank walls and large-diameter pipe where both stiffness and tensQe strength are required. Textile braiders have also been adapted for use as continuous... 

The melt mixers are either batch or continuous type. The formers require lower investment cost, but are more labor-intensive, have low output and poor batch-to-batch reproducibility. Recent developments in process control and automation eliminated some of these disadvantages [Utracki, 1991]. The continuous melt mixers comprise extruders, continuous shaft mixers and specialty machines — these will be discussed in the following part of this chapter. A brief overview of the melt mixing devices is given in Table 9.8. 

Commercial laundry and commercial dishwashing, in which specialty machines may require specialty detergents. Even dry cleaning may require detergent stain removers. 

Specialty Machines. Machinery can usually be designed to accommodate any reinforcing fiber and resin system on the market today. Since the goal is the lowest possible cost, the industry usually employs roving or tow as the cheapest raw material, and thermoset polyesters and vinyl ester resins, rather than epoxies, for the highest running rates. 

The melt mixers are either batch or continuous. The former requires lower investment cost, but is more labor-intensive, has low output and poor batch-to-batch reproducibility. The continuous mixers are extruders, continuous shaft mixers and specialty machines. 

Injection Molding. Matched metal molds are used in the fabrication of plastic closures, specialty packages, and botde preforms. In conventional injection mol ding the plastic resin is melted in an extmder which forces a measured quantity or shot into a precision-machined chilled mold after which the nozzle of the extmder is withdrawn. 

Clean Air Machine Corp. Air purifiers - commercial site offers customized filters for specialty applications aimed at removal of microscopic particulates and gases. http //aco.ca/tibbits/index. html... 

Plasticator A very important component in a melting process is the plasticator with its usual specialty designed screw and barrel used that is used in different machines (extruders, injection molding, blow molding, etc.). If the proper screw design is not used products may not meet or maximize their performance and meet their cost requirements. The hard steel shaft screws have helical flights, which rotates within a barrel to mechanically process and advance (pump) the plastic. There are general purposes and dedicated screws used. The type of screw used is dependent on the plastic material to be processed. 

The manufacturing processes for textile filament, staple and industrial filament yams have become so specialized that it is not possible to make one such class of fibers on the others equipment. Within these classes, there are production machines specialized for certain types of fibers for specific types of consumer products. Large machines designed to produce high volumes of commodity products (e.g. staple for cotton blending) at high efficiency and low cost are not well suited to the efficient production of specialty staple variants (e.g. fibers with special dyeing properties) and vice-versa. 

An alternate procedure used in a few specialty applications is the cuprammonium process. This involves stabilization of cellulose in an ammonia solution of cupric oxide. Solubilization occurs by complex formation of cupric ion with ammonia and the hydroxyl groups of cellulose. Regeneration of cellulose, after formation of the desired products, is accomplished by treatment with acid. The main application of the cuprammonium process is for the synthesis of films and hollow fibers for use in artificial kidney dialysis machines. The cuprammonium process yields products with superior permeability and biocompatibility properties compared to the xanthation process. Less than 1% of all regenerated cellulose is produced by the cuprammonium process. 

No necessity for scale-up experiments The granulation and drying of subunits of 7-9 kg, instead of a whole batch, gives the possibility to use the plant for laboratory and production scale, because the batch size is no longer characterized by the machine size, but by the number of produced subunits. Using the same plant in Galenical research, development and production may shorten the time to market for new solids specialties. 

Solution-cast film is produced on a larger scale for medical applications, battery separators, or other specialty uses with machinery of the type shown in Figure 3.2 [2], Viscous film is made by this technique. The solution is cast onto the surface of a rotating drum or a continuous polished stainless steel belt. These machines are generally enclosed to control water vapor pickup by the film as it dries and to minimize solvent vapor losses to the atmosphere. 

Anionic starches are obtained by reaction with phosphoric acid and alkali metal phosphates or by derivatization with carboxymethyl groups.30,31 This modification is primarily used to introduce amphoteric properties into cationic com starch for application on the wet end of the paper machine. Anionic starches with carboxymethyl substitution are used as thickeners in coating colors or as binders in coatings for specialty paper grades. Oxidized starches are inherently anionic but without thickening action. Potato starch already carries sufficient natural anionic charge to provide amphoteric properties after cationization.32... 

Tensile (and compression) tests on agglomerates can be accurately and reproducibly performed with a variety of general purpose or specialty testing machines (see references 17 and 18, for example). These machines contain at least three elements for (1) gripping the specimen, (2) deforming it and (3) measuring the load required in performing the deformation. Other features... 

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