Reaming allowance

Ideally, reaming allowances should be 0.1 mm per 5 mm of diameter, i.e. for a finished reamed hole 020 mm, the pilot hole should be approximately 019.6 mm. However, drilled holes prior to reaming should be standard size, wherever possible. 

Most rigs are now fitted with a system whereby the drill string is rotated by a drive mechanism in the mast rather than by the rotary table at rig floor level. Thus 90 foot sections can be drilled before connections need to be made, and the drill string can be rotated while pulling out of the hole in 90 foot sections. This improved system, which speeds up the operation and allows better reaming of the hole is known as top drive. 

The CPA or "Snake Pen" consists of a pen body containing a porous wick, such as that used in felt pens, and a solution ofDMSO and any number of toxins. When the wick is touched to the victim s skin he receives a fatal dose of poison. The CPA is built from a correction fluid pen, available at any office supply store. These pens have a soft, flexible body and are easy to modify. Unscrew the top from the son pen body, squeeze out the correction fluid and flush the interior with solvent to remove all traces of its original contents. Note that most of these pens have a left-hand thread on the body. The tip of the pen is sawed off and the valve stem carefully removed. Ream out the pen tip to fit the wick. A felt tip marker pen works well as a wick, after being soaked and rinsed in sol vent to remove traces of ink. It may be necessary to trim the wick to fit. Press the wick into the pen tip until about 3/8 " protrudes and seal around it with silicone sealer. When the sealant is dry, put on rubber gloves and, using a hypodermic syringes, inject the DMSO solution into the pen barrel until it is about 3/ 4 full. Be sure not to squeeze the pen while accomplishing this. Coat the barrel threads with a little silicone sealer, screw on the cap and allow the pen to dry in a vertical position. Line the inside of the cap... 

A 1/2-inch long piece of 1/4-inch steel pipe is fitted into the coupling. This is reamed with a drill to snugly fit a. 30-calibcr carbine cartridge case or whatever is available. The carbine case is of a size that allows the insertion of a commercial nonelectric blasting cap with no modifications. 

The bomb is then placed in the jacket, and the gas inlet tube is fastened securely. The thermocouple is also inserted. From this point on, all operations should be performed on the other side of the wall separating the operator from the equipment. Hydrogen is bled into the bomb from the high-pressure tank, the valve to the tank is closed, and the bomb is allowed to stand for about a half hour in order to test for leaks. If a leak has developed, as indicated by a drop in pressure, one locates it by painting all the joints with a soap solution and looking for bubbles of gas, which indicate a leak. The connector is tightened, and if this does not stop the leak, the pressure in the system should be released, the connection disassembled, and the tapered end of the tube re-formed with a tool supplied for the purpose. These measures usually will stop the leak, but if they do not, it will be necessary to ream out the connector seat with the reamer designed for this purpose. 

As in Figure 11. cut two 1/8 inch rings from the scrap tubing to fit in the middle of the holders. This allows you to automatically push each section an equal distance to the middle. With a round file or sharp knife, ream out any rough edges or burrs from the inside edges of the tubes and rings. 

Before the final reaming and lapping operations are performed on the sleeve, four parallel rows of vent holes should be drilled along the axis of the bore. These allow gas to vent into the absorbent material surrounding the... 

Perren, 1989], The IM naQ which has not been interlocked allows interfragmentary compressive force due to its low resistance to axial load. Another advantage of IM nails is that they do not require opening the fracture site, since they can be inserted through a small skin incision, typically located in one extreme of the bone. The insertion of an intramedullary nail, especially those that require reaming of the medullary canal, destroys the intramedullary vessels which supply two thirds of the cortex. However, this is not of clinical significance because revascularization occurs rapidly [Kessler et al., 1986 O SluHivan et al., 1989]. 

Nitroglycerin (combined with other substances to render it nonexplosive) can be administered in small tablets, which are placed under the tongue during an attack of angina. The nitroglycerin is rapidly absorbed into the bloodstream and finds its way to the heart muscle within seconds. It can also be applied directly to the skin as a (ream or absorbed through the skin from a transdermal patch attached to the skin. This last delivery system is a recent development that allows the nitroglycerin to be continuously absorbed for 24 hours. 

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