DE1095180B - Charging hose combination - Google Patents

Description

GERMAN

The invention relates to a method and means for applying a charge of water responsive Explosives in a blast hole and in particular a method and means for loading a water-containing blast hole with a water-sensitive explosive.

Blast holes are generally prepared using air drilling or wet drilling methods, and in some very resistant formations of extreme hardness, such as taconite z. B., the hole will be with Jet-drilled using a high temperature hydrocarbon oxygen flame. In some cases were such holes prepared to depths of more than 30 m. The holes are made with conventional cartridges loaded with explosives detonated in the hole. Often, however, this occurs when using them Procedure presents certain difficulties. Leachate fills such holes to a considerable extent Downs from; consequently, expensive, highly watertight packaged explosives have had to be replaced by cheap water-responsive compounds such as ammonium nitrate and the like can be used. In addition, the blast holes could be drained, but then rain could make completely shamed this result; in the same way can any packs, bags or sacks with water-sensitive explosives that stack near the holes for loading to stand by, seriously impaired from the standpoint of their use as explosives will.

Another disadvantage of previous blasting methods is that the walls of the hole quite often are not completely regular and therefore cause the explosive cartridge to become temporarily jammed in the hole can, which prevents their onset to the bottom, as well as an air pocket below and is formed around the cartridge. It is well known that such air pockets have a cushion effect cause which reduces the effectiveness of the blasting.

According to a currently used method of loading such blast holes with partial solution of the problems mentioned above, the arrangement provides a lot of an inexpensive, water-responsive one Explosive in a waterproof, flexible, plastic, possibly weight-loaded at the end Bag before, which then into the water containing borehole for the purpose of detonation is lowered. However, it has been found here that such bags often either through physical handling, contact with sharp-edged wall surfaces within the Loches or rock vibrations from our charging hose combination

Applicant:

Union Carbide Corporation,
New York, NY (V. St. A.)

Representative: Dipl.-Ing. H. Goertz, patent attorney,
Frankfurt / M., Schneckenhofstr. 27

Claimed priority:
V. St. v. America January 13, 1958

Robert Bruce Aitchison, Panama City, Fla. (V. St. A.), has been named as the inventor

Blastings are riddled with holes. As a result, water seeps into the bag or pack and at least partially dissolves the water-sensitive explosive, thereby reducing its effectiveness as a such substance is degraded.

In order to avoid these difficulties, a lining made of waterproof paper was also used or cardboard is suggested between the plastic bag and the inner surface of the borehole. Such a lining means an additional measure during the charging process, quite apart from that of the fact that full protection, if not particularly great care, would be taken, not up to would reach to the bottom of the borehole.

Another difficulty faced was that the pouch was blocked during its insertion experienced twisting or folds in the borehole, which were not completely corrected when the load was introduced disappeared, with the result that between the bag and the surface surrounding it the Lining or borehole air pockets remained. To take this into account already proposed further to inflate the bag with gas before the charge is introduced. Will but the shape of the bag is adapted to the surrounding surface in this way, on the other hand, there is the There is a risk that the bottom of the bag, which remains unprotected even when a lining is used, against a sharp corner or edge is pressed and pierced.

The aim of the present invention is therefore first to provide a charging hose device

009 678/190

3 4

Fig. 5 a longitudinal section of the triple pipe damage of the part which takes the load formed according to Fig. 4 after the weighting action, which can also be easily and quickly arranged in the pocket at the lower end the outer one and the tube inserted in the desired length at the tube hole and the bag closed from a prefabricated unit,
falling hoses can be provided. Figure 6 is an elevation of the triple tube structure

According to the invention, this device is in the Fig. 5, after the structure is longitudinally folded essentially characterized by a thin-walled, and tied together in order to be able to use it conveniently in the collapsing hose structure with an inner hole,
Inflation hose relatively small diameter io Fig. 7 is a view of a longitudinal section through a knife, an intermediate charging hose considerably blasting hole, into which the triple tube structure has been lowered to a larger diameter and an outer protective Fig - intermediate tube,

catching the intermediate hose, the inner Fig. 8 is a similar intermediate view of the three-hose openings near its lower end of the explosive hole according to FIG. 7 containing a compartment tube, sits and below the openings together with the after the intermediate pipe with an explosive intermediate hose is tightly closed while the mixture is loaded according to the present invention the outer hose has been removed via such a joint,

seal extends and ends in a pocket showing a Fig. 9 is a similar view of the triple tube

Contains crushed weight-bearing material. 20 containing explosive holes according to FIG. 8, after

To produce this device, the tubular structure containing the explosive mixture is

the further invention preferably fills three hoses, was tightly closed and bolted,

one of which fits into the other; and Fig. 10 is a perspective view looking downward

which end in a common cutting plane, with a plug for the upper ends of the

a desired length of the outer tube on 35 intermediate and outer tubes,

is folded back on itself, the intermediate tube Fig. 11 is a perspective view looking down on

along the inner tube near the fold back a clip that follows the stopper

of the outer tube is separated, the side of FIG. 10 fits around so that the upper ends

Openings in the inner tube near the back of the intermediate and outer tubes in between safe

folding are provided, the intermediate hose are held closed,

together with the inner tube essentially FIG. 12 is a perspective view looking downwards

sealed at the severed ends of the same on a chair structure to support the closure

the outer tube immediately below the plug and the clamp according to FIGS. 10 and 10, respectively.

the sealing of the intermediate and inner hose 11, and

is unfolded and sealed, the bag with a 35 Fig. 13 is a perspective view downwards

Amount of crushed weight-bearing material on a hopper that is inserted into the stopper

filled and this material fits by tightly closing according to FIG. 10, for the purpose of loading the

the lower end of the outer hose injected explosive mixture into the intermediate tube,

is closed. Fig. 1 illustrates a triple tube structure for

The loading hose formation according to the invention is 40 loading of blast holes according to the present invention

preferably of prefabricated lengths of the three invention. The structure has an internal inflation

specialist hose combination manufactured, the folded or tube 20, which is relatively thin-walled,

wound is kept ready. preferably a wall density between 25 and

The new invention can also be made to have 50 microns. The inner tube can do one

design advantageous that they have a further protection 45 diameter of 1.3 to 3.3 cm and a flattened one

against moisture conveyed by a cargo width of 1.9 to 2.5 cm. To this tube

can, which is made of a hydrophobic explosive, an intermediate tube 21 is provided which

stands, which is specially made of a moisture-sensitive preferably a wall thickness between 50 and

Explosive, e.g. B. ammonium nitrate, which is 75 microns and a diameter of 15.9 to

a gelled liquid hydrocarbon, e.g. B. ge 50 40.7 cm or any of the diameter of the

lated kerosene. Blast hole has the required diameter. the

Other Features, Advantages, and Applications Outer tube 22 preferably has a wall thickness

possibilities of the new invention result from between 50 and 75 microns and a diameter,

the representations of exemplary embodiments and which is large enough to surround the intermediate tube 21

from the following description. It shows 55 close. The tubes 20 to 22 are made of flexible,

Fig. 1 is a side view, partially in cross section, water-impermeable material, such as strong, organic

a threefold, composite plastic pipe nischem plastic material, z. B. polyethylene,

formed according to the present invention, polyethylene terephthalate, polyvinylidene chloride and the like.

Figure 2 is a view of a section of the interior molded. This tube structure can be in uniform

Tubular part according to FIG. 1, disassembled for the purpose of being made 60 lengths or as long as it is

Preparation of such a unit for insertion conveniently on a reel for shipping purposes

the blast hole, or the easy handling.

Fig. 3 is a view, partly in cross section, of Figs. 2 to 6 illustrates the method of Fig triple tube structure according to Fig. 1, after the preparation of the tube structure for the purpose of the exterior Pipe section pulled down and transversely tight 55 put into the blast hole. About 30 to 60 cm des Has been sealed, the end of the outer tubes 22 will be on top of the tube

Fig. 4 shows a longitudinal section of the triple tube itself turned back to a part 23 of the formed along line 4-4 of FIG. 3, each of the intermediate tubes 21 being exposed. This part becomes tubes is tightly closed transversely, according to the lengthwise together with the enclosed inner tube invention, 70 of line 24 near the fold back of the outer tube

5 6

cut off and excreted, so that at the end of a water-sensitive explosive, Pipe structure an outer pipe skirt or skirt 25, the folded and weighted pipe structure remaining. The unseparated inner tube 20 is lowered according to FIG. 6 with the aid of cords 35 is then at the points 26 near the folded back until the weighted, bag-like cover 29 a notches. Then it rests transversely to the inner and 5 preferably on the bottom of the hole or theirs Intermediate tubes 20 and 21, below the notch 26, natural level below the surface of the at about the separation point, e.g. B. by means of heat, looking for water. The upper edges of the intermediate and tight closure 27 is provided. This closure outer tubes are then closed around a the bottom of the intermediate tube 21 tight and closed plug 37 pulled around and with the help of a anchored the inner tube 20 with the intermediate tube io adjustable ring clamp 38 pressed against it, the 21. The outer tube is now unfolded and preferably tied on legs 39 as a chair 40 Sealing 28 is just placed transversely to this tube. The inner tube 20 fits into a hole 41 half of the sealing point of the intermediate tube so in front of the plug 37 and is under pressure at one seen that a pocket 29 from the skirt or standing gas source, e.g. B. compressed air source, attached apron 25 is formed. This sealing procedure 15 completed. A hopper 42 fits into a hole 43 in the forms an inter-tubular bag 30 within a plug 37. A pressure relief valve outer tubular bag 31, which provides greater security 44, in turn, fits into another hole 45, as well against the ingress of water into the explosive charge in the sealing plug 37.

holding intermediate bag 30, as further more precisely now, compressed gas is passed through the inner is guaranteed. The tubes let tube 20 blow in and escape through notches Alternatively, they can also be formed into bags by inserting the 26 into the intermediate tube at a point near the Brings ends together as required and with the lowest part of the area of the pipe structure that a cord or other fastening means is pressed together by means of water pressure. This binds together. The heat seal, however, works to ensure that the tubes are inflated evenly when one becomes dense with heat. The paper tapes or something else that can be locked, e.g. weldable, plastic work holding the pipe structure together in the folded state Material is used, as this quickly becomes a cheaper, means used are easily destroyed by the gas pressure nevertheless reliable tight seal burst.

is won. When the tube structure is inflated so that the bag 29 is partially filled with weighting 30 outer tube 22 with the hole walls in BeMaterial 32, such as rock fragments or a soluble contact, including the walls of any material, as described later, filled and the one above which, if applicable, widened Schüssige skirt or apron material with the help of parts 46, the explosive mixture 47 is in the pipe suitable Means such as a string or a ribbon formed. Such an invitation can be 33, to form a bag-like envelope 29 α ab- 35 bound by air pressure on the upper part of the funnel. The latter is also, preferably at easier. Loading of the plastic pipe structure a point near or just below the ab- caused by excessive pressure being caused by the uncut 27 and 28, tied. Avoided for this relief valve 44, which is set so bind used cord 34 od. The like. Can with that at the desired maximum pressure in the aufeinem or two ends 35 are left long enough to open 40 blown intermediate tube 21, den, to the full depth of the borehole- If the hole is partially filled with the explosive mixture suffice. Such cords can be used to load 47, the plug 37 is used for the tube containing the weighting material is used for inserting the first initial cartridge 48 sent formed into the borehole, such that the at an intermediate level above the bottom of the Pull on the plastic tubes is reduced. The pipe structure to be 45 removed. After the first initial compound The tube structure is then lowered to its correct place in the preferred cartridge folded several times in the longitudinal direction as has been, it can e.g. B. with fuse 6 to provide a narrow width of a 49 to be provided in notches 50 in the closure final structure conveniently provided in a plug 37. Next is the Borehole can be lowered without doing so in 50 inner tube 20 removed, if desired by an excessive Contact with the raw surface of the fold pulling out, as it tears off at the notches 26. To get perforated walls. Such folds 36 leave after the remainder of the explosive as well as an or by using paper tapes 36 a around more additional initial cartridges have been invited around the folded structure or by use, the upper part can be the intermediate and outer Small pieces of pressure sensitive tape keep 55 tubes 21 and 22 tied and the rest of the or by applying a small amount of a hole as illustrated in Fig. 9, caulked suitable adhesive substance between the folds.

each of which is relieved by a slight pressure and is a pipe structure of at least 15 m in length is released. Usually required in a 14 m deep hole to borrow a blast hole containing water. The reason for this is that the shape load, the bag in the hole will preferably match the irregularities of the wall of the hole Water volume to not more than about 1 to IV2 m approximates to a very considerable degree, if the free-depth, Calculated from the ground, limited and any explosive charge flowing into the bag in excess Water removed. If desired, can 'falls. Where no additional pipe length is available If a suitable amount of water is seen in an irregular shape, the pull of such a shape can be achieved dry hole poured into it to make the bags tear apart, Avoiding a wall of air, which is the shock waves An advantage of the present invention the detonation could interfere. in that even if the outer plastic tube From FIGS. 7 to 13, the method and 22 are torn or perforated during loading Device for loading a blast hole with 70 would be, the intermediate tube 21 still a

forms an effective moisture barrier. Accordingly, when the top of the tubes is tied off, one can left a loaded hole to its own devices for an extended period of time before blasting. This allows enough Time to reload lots of holes to make one big blast that way to prepare without the risk of moisture penetrating the explosive mixture.

While the described method of loading blast holes leads to the practical advantage, that a cheap, water-sensitive explosive such as ammonium nitrate can be used, it is also advisable to avoid the moisture-related problems that arise would if the untreated explosives were used and both the intermediate and also outer plastic bag perforated or otherwise damaged in particular near the bottom of the hole should be.

It has been found that the explosive power of ammonium nitrate in the form of small lumps can be increased significantly by adding a liquid hydrocarbon. Treatment with liquid hydrocarbons, such as kerosene or fuel oils, increases the sensitivity to water of ammonium nitrate to a specific one, but not sufficient for the present purposes Degrees down.

The water repellency of cheap, water-sensitive explosives can be strongly penetrated Incorporation of a hydrophobic thickener into the agent to be mixed with the granular explosive Increase hydrocarbon liquid. As a thickening agent, metal soaps have proven to be appropriate proven. For example, kerosene was used as the hydrocarbon liquid in one experiment and him an aluminum soap of a 2-ethylhexo acid in the proportion of 7Va parts by weight of soap added to 100 parts by weight of kerosene. The soap was made in the kerosene by stirring and heating completely dissolved to about 51 to 66 ° C; after cooling, the liquid took on a thick consistency at. Ammonium nitrate in lump form was then added to form a free-flowing slurry. The proportions were about 5.2 liters of the solution to 50 kg of ammonium nitrate. According to the present Invention achievable higher water repellency was made visible by stirring Ammonium nitrate with the jelly-like hydrocarbon mixture, stripping off the excess liquid and placing the otherwise unprotected ammonium nitrate in a cold water bath. It was easy to see that the thickened hydrocarbon the ammonium nitrate grains with a protective film covered, and only after 35 minutes did the water noticeably dissolve the ammonium nitrate instead of. This compares favorably to a similar attempt in which the uncoated Ammonium nitrate was placed in cold water and was found to dissolve instantly, as well with a third attempt in which ammonium nitrate was coated with untreated kerosene, in cold Water and it was found to dissolve in less than two minutes.

When the gelled kerosene-ammonium nitrate mixture is loaded into the plastic bag in a borehole, only a very small area of the mixture adjacent to a possible perforation of the intermediate tubular bag can be subjected to the action of water in the borehole. The dissolving effect of the water is therefore delayed so much that only a very small part of the explosive can be inactivated when exposed ^{to water for periods of time much longer than 1 hour.}

If aluminum soaps with hydrocarbons of the kerosene type are used, about 3 percent by weight is sufficient the soap to give the liquid a jelly-like consistency with the preferred upper limit although aluminum soap can be used up to about 10 percent by weight. Other liquid hydrocarbons useful in practicing the present invention are gasoline, kerosene and fuel oil. Also other well known thickeners that are hydrophobic, come into consideration, such as colloidal lamp blacks, colloidal silicas and mineral waxes. That Hydrocarbon thickener mixture should be at least about 10 percent by weight of the explosive turn off.

It is important that the batch fills the explosive part of the hole as completely as possible to avoid air pockets to avoid who strive to buffer the explosion and the explosion performance Reduce. For this purpose, a weighting material is preferably used that has a high water density possesses and is crushed finely enough to be distributed over the bottom of the blast hole in such a way that Air gaps can be avoided. Because water in the blast hole contributes to all the gaps as one incompressible, shock-transmitting agent, it is advantageous to fill the bag of the weighting To punch through the material so that water mixes with the material and the spaces between the can fill out individual particles. Instead, the crushed weighting material can be made from a water-soluble one Substance, like a metal salt, exist that when water is appropriately sized small openings, slowly dissolves and in this way the explosive charge above allows to sink down and the bottom part of the blast hole tightly and completely with active Fill in explosives.

Claims (5)

Patent claims: 1. Charging hose combination made of waterproof material for charging those that are exposed to moisture Holes with moisture-sensitive explosives, indicated by a thin-walled, collapsing tube structure, with an inner inflation tube (20) relatively small diameter, an intermediate charging hose (21) considerably larger Diameter and an outer protective tube (22) of sufficiently large diameter to encompass of the intermediate hose (21), the inner hose (20) having openings (26) close to its has the lower end and is tight below the openings together with the intermediate hose (21) is closed, while the outer tube (22) via such a common seal (28) extends and ends in a pocket (29) containing a crushed weight-bearing material (32) contains. 2. Combination according to claim 1, characterized in that the openings (26) in the interior Hose (20) are notched to allow their separation by pulling for subsequent removal facilitate. 3. Combination according to claims 1 and 2, characterized by a pair of twine (35) which tie off the top of the bag (29) and be long enough and strong enough to hold the weight-bearing Facility to allow them to pass through the twine without undue drag on the Tubing is lowered into the borehole. 4. Combination according to claims 1 to 3, characterized in that the pocket (29) is perforated and contains a weight-bearing material that is at least partially soluble in water. 5. Combination according to claims 1 to 4, characterized in that it is above the pocket (29) has longitudinal folds (36) which are held by tapes, strips or bandages (36 a), the are easily detachable when internal pressure is applied to the hose device. Considered publications:
German Patent No. 932 595;
British Patent Nos. 778 760, 785 140;
U.S. Patent No. 2,745,346. 1 sheet of drawings © 009 678/190 12.60