Thread Tapping

Tap each hole for a 34" NPT thread. Tap every hole on a disk from the same side, as the thread is a tapered fit and all fittings enter from one side only. 

This description applies equally to assemblies using threads tapped in the plastic or to self-tapping screws. Screws are generally used for larger assemblies, such as enclosures for electrical apparatus, etc., and for any size assembly that must be taken apart for servicing or into which are fastened other components which may have to be removed fm servicing, etc. 

Another frequent operation when developing devices for the laboratory is the realization of threaded, whether male using the dies or taps (Figure 4.6). In FIA standard threaded taps and dies are used i.e. 14"-28, while the standard for optical fiber is 4"-36. 

FIGURE 12.13 Thread forming and thread tapping screws. 

Threads can be molded or tapped into a plastic. Molded internal threads usually require some type of unscrewing or collaps-... 

Finally, self-tapping screws require additional torque to cut or form their threads. This... 

It is not possible to fabricate a practical anode such as that shown in Figs. 20 and 21. One approach is to drill and tap a hole in the carbon piece and screw a piece of threaded copper into the hole. This works fairly well for a hole 10 cm deep, perhaps 15 cm deep if one is careful, but not very much beyond that. There are two major problems (1) It is difficult to get a good... 

Tapped holes for flange bolts shall be of sufficient depth that the thread engagement will be at least seven-eighths of the nominal thread diameter. 

Self-tapping inserts available in thread-cutting or thread-forming types. The advantages and drawbacks of this process for the thread-forming type are ... 

Unless otherwise specified, pipe threads shall be tapered threads conforming to ANSI/ASME Bl.20.1. Tapped openings and bosses for pipe threads shall conform to ANSI/ASME B 16.5. 

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