Blanking layouts

Figures 10-25A-E are for U-bundle tubes and require a wide blank space across the center of the tubesheet to recognize the U-bend requirement at the far end of the tube bundle, see Figures 10-lE, 10-lAitem U, and 10-lK Figures 10-25F-Kare for fixed tubesheet layouts.

Figure 4.19. Layout of a unit for centrifugal casting (molding) of tubular blanks 1 - rotary mold 2 - mold rotation rollers 3 - heating chamber 4 - blank 5 - rotary gripper of finished pipe extender 6 - exhaust ventilation.

Figure 1. The layout of the channels (right) and mixing by electroosmotic flow and pump flow (left). Right 1. sample cell 2. sample waste cell 3. buffer cell 4. the inlet for luminol solution 5. the inlet for H2O2 solution 6. reaction cell 7-waste cell. Left 1. electroosmotic flow 2. pump flow 3. waste a. blank b. Rhodamine B enters the reaction cell (electroosmotic flow) c. electroosmotic flow and diffusion in reaction cell d. steady state of electroosmotic flow and pump flow.

Mould layout becomes more critical in the case of multicavity mouldings where it is essential that each mould operates under similar conditions. Although it may occasionally be necessary to blank off a mould or moulds (e.g. damaged mould inserts), there is always a possibility that this may upset the delicate balance between mouldings. 

When parts are to be blanked from strip material, it is essential that the blank is arranged within the strip to gain the greatest economical use of the material by minimising the amount of scrap produced. The final layout will determine the width of strip, which in turn determines the general design and dimensions of the press tool. 

Now consider the blank shown in Fig. 16.21> to be produced from 19 SWG (1.0 mm) material. The simple layout would be as shown in Fig. 16.22(a). This gives a strip width of 32 mm and a feed of 31 mm, allowing 1mm between blanks and between blanks and the edges of the strip. Thus the area of strip used per blank would be 32 mm x 31 mm = 992mm. ... 

This gives the most economical use of the material and would therefore be the obvious choice. However, with this layout the strip would have to be worked in two passes. On the first pass the bottom row would be blanked the strip would then be turned round and passed through again for the other row to be blanked. 

Explain the importance of the layout of blanks in strip material used in the blanking and piercing process. 

An alternative layout with the blanks turned through 45° is shown in Fig. 17.22(b). In this... 

A further alternative layout is shown in Fig. 17.22(c), with the blanks in an alternating pattern. This gives a strip width of 48mm and a feed of 32 mm, which in this case produces two blanks. Therefore the feed per blank is half this amount, i.e. 16mm. Thus the area of strip... 

The layout for the top mold half is shown in figure 80. Center tlie blank in the 4-jaw chuck. Center drill and then drill through with a 5/16" drill bit. 

In the hot-embossing process a heated die carrying the negative of the conductor layout presses a specially coated copper film on to a thermoplastic substrate, applying thermal loading and mechanical pressure. The die cuts out the film, forming a positive bond to the locally melted plastic close to the surface of the blank. Figure 3.16 shows the process chain in simplified, schematic form. 

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