Drilling and tapping

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... 

The bottle jack on the hydraulic press was drilled and tapped to accept a J4 inch NPT pipe to connect to a pressure gauge. 

The use of tapped holes in pressure parts shall be minimized. To prevent leakage in pressure sections of casings, metal, equal in thiekness to at least half the nominal bolt or stud diameter, in addition to the allowance for corrosion, shall be left around and below the bottom of drilled and tapped holes. The depth of the tapped holes shall be at least... 

Drill and tap the center of the aluminum disk to thread onto the barrel (%"x 24 tap). 

Drill and tap the front tube for two alien set screws each at the three points indicated (six screws total)(figure two). 

Drill and tap the muzzle end of the tube and install a standard shotgun bead sight. Deburr the hole inside the barrel. 

Thin wahed brass tubes are easily joined togs er with silver solder. Aluminum tubing can t be soldered but is easily held together with screws-because the wall thickness Is sufficient to hold threads. The holes can be drilled and tapped In the conventional manner or simply drilled with a hand drill and threaded with self tapping machine screws. 

Mark a center line on the top rear of the 8 tube. Measure 5/8 down each side from the center line and mark the tube. Measure 1 from the rear of the tube and mark again,intersecting the first 2 lines. These two points are the location for the tube support screws They can be drilled and tapped for machine screws or simply drilled for self tapping screws or pop rivets. Be sure that whatever fasteners used do not extend through the collar into the barrel itself. This allows the collar/ tube assembly to be removed from the barrel by loosening the bottom screw only. 

Cut the sole leather into approximate sizes Drill or punch holes through the centers and slip them onto the tang. Drill and tap the end ferrule, and screw it lightly on the end of the shaft, which baSvpreviously been threaded. 

Taking the Receiver, drill and tap fno-2 < hole for Trip Lever Pivot, center punch. Use a 1/8 or //9 drill bit. Use a 10-24 starter tap. 

A fairly heavy rawhide mallet is used to ram the composition, mainly because a solid metal hammer would soon deform the top of tbs drifts. (Note a rubber mallet is completely unsatisfactory it does not deliver enough impact to consolidate the clay or powder properly.) The spindle itself should of course be installed on a substantial base, such as a block of hardwood this can be done by drilling and tapping the underside of the metal shoulder and running a 5/16 or 3/8 bolt up through the wooden base, after recessing the bottom to accept the head of the bolt ... 

The electrolyzer body consists of a threaded stainless steel pipe nipple with drilled and tapped holes for positive electrodes. The top and bottom caps are stainless steel flanges (four flanges in total) with flange seals and bolts and nuts. 

Blind flanges, drilled and tapped. Left, top flange and right, bottom flange. 

Drill and tap 3 holes for 34" NPT fittings in the top disk and one in the bottom disk (see schematics on next page). 

You can design and build coalescer and filter bodies, and filters. Stock parts can be used with a little drilling and tapping. Filter material can be polypropylene or glass cloth. Do not use organic fiber materials for filters in these systems - they are not compatible with KOH. 

Drill and tap for 34" NPT ports in box McMaster-Carr, hardware store... 

Drill and tap two holes across from each other on one of the end caps. 

This will be the top cap of the bubbler. The holes are the entry and exit ports for the gas, and accommodate two 90° barb connectors. Drill and tap a hole in the center of the bottom cap for the third barb connector. Trim the barb connector... 

Polyethylene, polyvinyl chloride and polypropylene are easily worked utilizing ordinary wood or metal working hand and power tools. Being thermoplastic, these materials can be easily thermo-formed as well as cut, sawed, drilled and tapped. In the heat forming process, electric ovens are generally used which can maintain good thermal control. Of the three thermoplastics, polypropylene requires the more finite thermal control. Table III provides approximate time and temperature relationship required for thermoforming these three plastics. 

Piping fabricators are well aware of the problem, and will instead provide a steel boss 1-1/2-inches in diameter by 4 inches long, drilled and tapped for a 1-inch pipe thread. This boss is welded into the pipe elbow as shown in Figure 7-87b. It is a more expensive operation than using an elbow adapter. 

A 4-inch blind flange is drilled and tapped for the 1-inch thermowell. To protect the thermowell... 

To facilitate the secondary operations of drilling and tapping, cored-through holes should have countersinking on both ends of the holes. 

A combined tap and drill is available in a range from M3 to M12. This comprises a spiral fluted tap with the front portion ground as a drill to a diameter equal to the appropriate tapping size (Fig. 8.18). These are used for through holes where the drilling and tapping can be carried out in one operation. 

When the two parts are to be screwed together, the bottom part requires to be tapped while the top part requires a clearance hole. The sequence is the same as for spotting except that, having positioned, clamped, and spotted with the clearance drill, the drill is changed to the tapping size. The hole is then drilled and tapped. Fig. 8.22. 

Some larger components are fitted with a drilled and tapped hole to accept an eyebolt to simplify lifting. Collar eyebolts, manufactured to BS4278 1984 are available with threads from 6 to 52mm with larger sizes available to order. Imperial threads are available for replacement on older equipment. Typical SWL of an eyebolt having an M45 thread is 8 tonnes. 

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