Blind drilling

Blind drilling (no returns) then set casing or cement. 

Blind drilling is common, aiming at a specific water horizon or aquifer. It is the hydrochemist s task to convince the drilling organization that drilling should be stopped at intervals, water removed so that new water enters the well, and the following measurements carried out ... 

In the press section the individual rolls are hard or soft covered. The press nip (Fig. 6.7) is created either by two profiled rolls or by a combination of one profiled and one plain roll. Covers with high open surface area, similar to tyre technology, offer the necessary storage capacity for the water squeezed out in the press nip. The various surface designs include grooves, blind drilled holes or suction holes as well as combinations of these. 

Polyurethane roll covers were introduced to the paper industry at the end of the 1980s. The outstanding mechanical and dynamical properties make polyurethane the most suitable material for soft elastomeric covers in press positions. Depending on paper quahty and press design, high open surfaces up to 45 % with grooves, blind drilled holes or suction holes, as well as combinations thereof are used. An example of surface design is shown in Fig. 5.11. 

Fig. 6.11 Example of surface design for polyurethane press cover (blind drilled and grooved) (source Voith).

Use the 3- in. stripper rubber in the rotating head to strip over the 4- in. drill collars until the drill bit is above the blind rams (but below the stripper rubber in the rotating head). 

Close the blind rams, open the rotating head to release the 3 in. stripper rubber, pull the rotating table bushings and raise the last joint of drill collar, remove the bit, and lay this Joint down (remove the 3in. stripper rubber from this drill collar Joint for later use). 

This rather complicated procedure has been necessary because the drilling rig can only accommodate the BOP stack that has only one set of pipe rams and a blind ram (i.e.. Figure 4-188). It is obvious if the rig could accommodate the taller BOP stack with two pipe rams (namely Figure 4-187), one pipe ram could be for 3 in. drill pipe and the other for the 4 in. liner. Such an arrangement would greatly simplify the safety procedures necessary for placing the 4 in. liner into the borehole. 

A formation fluid kick can be efficiently and safely controlled if the proper equipment is installed at the surface. One of several possible arrangements of pressure control equipment is shown in Figure 4-351. The blowout preventer (BOP) consists of a spherical preventer (Hydril), blind and pipe rams, and the drilling spool. 

With few exceptions, most blind U deposits and other potential sources of He are situated below the water table, so that He must be released into the groundwater prior to its escape to the soil gas and the atmosphere. In consequence, groundwater, or at least groundwater as represented by water in drill holes and wells, has been sampled extensively as a means of determining the dispersion of He. Surface waters, however, tend to be equilibrated with the atmosphere and are unsuitable as sample media, except when collected from springs and at depth from lakes. 

Sakrison (1971) briefly described a halo of anomalous Hg in drill core and surface rocks associated with a blind massive sulphide deposit near Noranda, Quebec. The halo... 

Drill Vie" holes in the two blind flanges as marked, two holes in each flange. 

Tap the four holes just drilled in the blind flanges for 34" NPT thread. Do not tap the thread all the way through the flanges. Tap each flange from the flat side, which will be the outside when electrolyzer is constructed. The flange faces that will be inside have a raised surface for gasket placement. 

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

Another allotrope of elemental carbon is diamond. Besides being blinded by the brilliance of a cut diamond, you should know that diamond is the hardest natural substance. It s often used on the tips of cutting tools and drills. Can the structure of diamond explain its hardness Look at the model of diamond. Every carbon atom is attached to four other carbon atoms which, in turn, are each attached to four more carbon atoms. Diamond is one of the most organized of all substances. In fact, every diamond is one huge molecule of carbon atoms. This organization of covalently bonded carbons throughout diamond accounts for its hardness. If you tried to write... 

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

Figure 1. Photograph showing the standard C/SiC sample with drilled blind holes on the other side.

For the composite panel with the drilled blind holes on the back side, a time sequence of thermal images was obtained by thermography. Figure 2 presents a series of thermographic results from t = 0.017s to 2.002s. These thermal images with time sequence exhibit a clear evolution of the hidden holes from invisibility to visibility at different depths. 

Before Fermi and his team moved to Illinois they built one more exponential pile, this one loaded with cylindrical lumps of pressed uranium oxide three inches long and three inches in diameter that weighed four pounds each, some two thousand in all, set in blind holes drilled directly... 

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