Runner types

Development The following discussion relates specifically to the use of what could be called radial-inflow, centrifugal-pump power-recovery turbines. It does not apply to the type of unit nurtured by the hydroelecti ic industry for the 1 ge-horsepower, large-flow, low- to medium-pressure differential area of hydraulic water turbines of the Felton or Francis runner type. There seems to have been little direct transfer of design concepts between these two fields the major manufacturers in the hydroelectric field have thus far made no effort to sell to the process industries, and the physical arrangement of their units, developed from the requirements of the hydroelectric field, is not suitable to most process-plant applications. 

Brown et al. (2, ) reported the following compositions in terms of pmoles per 100 g of oil from Spanish-type (S) and runner-type (R) peanuts total carbonyls, 116 (S) and 62 (R) dicarbonyls, 36 (S) and 30 (R) ketoglycerides 69 (S) and 24 (R) and monocarbonyls, 10 (S) and 8 (R). They suggested that the differences in carbonyl contents were due to differences in linoleate contents between the two peanut types. A longer storage period for the Spanish-type was postulated to allow more autoxidation to occur even though the peanuts were in cold storage. 

FIGURE 4.5.18. Configurations of mercury cell anodes (a) blade type (b) runner type (c) rod type (d) mesh type [106]. (Reprinted by permission of John Wiley Sons, Inc.)... 

Regranulation of the feed system of a cold runner type mold may be accomplished by using a work handling device so that the feed system, when removed from the mold, is... 

The insulated runner type of runnerless mold and certain types of hot sprue bushings can be used for UPVC, however careful consideration needs to be given to the relative thermal stability of the molding compound (i.e. the type of stabilizer system used) and the anticipated cycle time at which the mold is expected to run at before deciding which approach to opt for. 

This type of mould, also often referred to as a three plate mould, is used when it is desired to have the runner system in a different plane from the parting line of the moulding. This would be the case in a multi-cavity mould where it was desirable to have a central feed to each cavity (see Fig. 4.38). In this type of mould there is automatic degating and the runner system and sprue are ejected separately from the moulding. 

Number of cavities, layout and size of cavities/runners/gates/cooling lines/side actions/knockout pins/etc. Relate layout to maximize proper performance of melt and cooling flow patterns to meet part performance requirements preengineer design to minimize wear and deformation of mold (use proper steels) lay out cooling lines to meet temperature to time cooling rate of plastics (particularly crystalline types). 

As reviewed in other chapters, different plastics have different melt and flow characteristics. What is used in a mold design for a specific material may thus require a completely different type of mold for another material. These two materials might, for instance, be of the same plastic but use different proportions of additives and reinforcements. This situation is no different than that of other materials like steel, ceramics, and aluminum. Each material will require its own cavity shapes and possibly have its own runner system. 

In addition to the process parameters, there are large numbers of factors that decide the success of an injection molding operation. Mold design, product design, position, and size of gates, type and positioning of runners, etc., are extremely important factors to be taken care of. A detail consideration regarding these factors has been discussed below [213]. 

Table 49-11. Types of muscle fibers and major fuel sources used by a sprinter and by a marathon runner.

Thomas and Watson ( 9) of the Oak Ridge National Laboratory have shown that detached spiral wire turbulence promoters, positioned away from an RO membrane surface by small wire runners, markedly increased the rejection of salts and the permeation rate through the membrane. "Detached promoters" of this type may be designed to minimize stagnant regions in addition, they are relatively easy to install. 

Medard and Le Roux [1] examined the influence of various methods of mixing on the properties of ammonium nitrate explosives ( Explosifs du type N ). They found that mixing in heavy (5 ton) edge-runners gives explosives of higher sensitiveness and rate of detonation than the same explosives mixed in kneaders of the Werner-Pfleiderer type. 

At this stage, one has to take into account the volume compressibility of the material, since upon feed-up the hold-on time of material under pressure is determined by compressibility and slow viscous flow. If the pressure of injection PQ is sufficiently high, then at this stage a liquid may be considered to be Newtonian with viscosity q ,. Keeping this in mind, we may state that the calculation given below will be applicable to various plastisols (of types I and II) with the only difference that for plastisol I q = const, while for plastisol II q = q. For the sake of simplicity, the analysis will be performed for the case of a flat mould filled through a slit runner (Fig. 10 a). 

Paper-based planner organizer systems. You may have heard of the Franklin-Covey planner system or the Day Runner system or seen them in stores. These are just two examples of popular paper-based organizing systems that go beyond the traditional calendar. These systems help the user to prioritize and schedule tasks and to keep a detailed calendar, master to-do list, and address book. They allow the user to customize it so that you only include the types of pages you use most. They come with instructions on how to best use their systems in order to get the most out of them. 

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