CA2147521A1 - Blasting components - Google Patents

Abstract

ABSTRACT
BLASTING COMPONENTS
A booster comprising a rigid PET container containing pentolite has an electronic detonator in the pentolite. The detonator is operated via a multi-core cable that extends therefrom. The cable is secured to the container by means of a cap screwed onto a neck portion of the container and/or by being knotted about a flange on the neck portion. The booster and the detonator are transported separately and are mated prior to use. The container is bulb-shaped having a body portion that is rounded at its bottom end and tapers upwardly to meet the neck portion. The cable is also sufficiently strong that the booster can be suspended thereby in a blasthole, explosive can be charged into the blasthole and the booster can then be lifted slightly, through the explosive, by the cable.

Description

21~7~1 ~Ig rNvENT~oN relates to bla~ting. More particularly, it relate~ to boosters an~ their associated detonator~. In particular it relate~ to a blasting component, a booster, the bla~ting component and the booster in combination and a mecho~ of blasting.

A~cording to a first a~pect of ~he invent10n there is pro~ided a bl.asting ~omponent wh~ch compri~es a detonator in~ertable in a booster;
a signal trans~itter ex~ending from the detonator;
an~
a securing member for securing the signal .
~ransmitter to the booster.
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According to a ~econd a~pect of the invention there i6 provided a booster whi~h comprises ;;
a co~tainer wh~ch is of a rigid materlal;
a guitable explosive material contained within ~he ` .
container; ~ :~
the container ha~ing an opening chrough which a datonator may be in~erted into the explosi~e material; ;~.
and with the container having a securing formation by `~
¦ means of ~hi~ih a signal trans~itter of the detonator may `.'~'. ~`'`:~.

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i` ~ 21~7~21 . - 2 -be 6ecured to the container.

It i6 co be noted that in some coun~rie6 the booster is known as a "pri~er".

According to a third a~pect of the invention there is provided an explo~ve component which inclu~es a booster comprising a rigid container tha~ i~
filled with an explosi~e material;
a ~etonator located in the explosive ~aterial; and a signal trans~itter for the detonator secured to the container.
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It will ~e appreciated that the ~ignal transmitter may be secured to the container indirectly, by means of the securing member or, directly. Still fureher~ the ~ignal transmitter may be secured to the container both by means o~ the securing me~`oer and directly. Thus, the signal cran~mltter may ~e wound around a ~ultable portion of the container and tied thereco.

Those s'~illed in the ar~ will understand thac the detonacor may be initiated in a number o~ ways, for example electrically, electronically. or by a fuse which could ei~her be of the shock wave or incendiary type.

In a particular embodiment, the de~onaeor ~ay ~' `' 2147~2~

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be electro~ically operable such thac the signal cransmitter comprises a multl-cored cable ~hich ~s fairly itrong. Thus, the cable may hsve a tensile ~trength of at least ~N, and, preferably, greacer than 400 N.

It will accor~ngly be under~tood that, by means of the invention, the booster and deeonator are only ma~ed i~me~iately p~ior co use go chat they can be stored and transporte~ separately which is desirable ~rom a safesy poin~ o~ ~ew.
,;" ~' Accordingly, immediately prior to u6e an~
~1~, the detonator i3 inserted in the booster and i8 secured thereto by ~eans of t~e signal eran~mitter, as indicated above. The boost~r, with the ~e~onator th~rein may the~ be lowered inco a blasthole by ~eans of ;.
th~ signal transmi~ter. ~he blasthole ~ay then be . -filled with explosive. The booster, together with t~e detonator may ~e lef~ at the bottom of the bla6thole whilst the blasthole is filled with explosive and m~y .
then be llfted a 5horc distance. by means of the signal trans~itter, to ensure that the booster is surrounded by .~ ;
the e~plosive. This is possible becaus~ the booster is secured to the sisnal transmiccer and the signal :~
transmiecer is sufficiently strong. In~tead o~ lea~ing the booster a~ the bottom of the blasthole whilst it is filled, th~ boos~er may be su~pended a short distance . .. , ,:. ::
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21~7~21 away from the bot~om of th~ blasthole, by ~eans of the 3 signal tran5mitter, whilst the blasthole i~ filled with I explosive.
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Seill fur~her, according to a fourth aspect of ~he inven~ion, there i~i provlded a method of blasting, which includes mating a detonator with a booster i~medlately prior to inEier~iOn of the booster into a blasChole.

The me~hod may include securing o~ a signal transmitter of the detonator to the booster.

The explosive material used with the boosCer may be that kno~n as "composition B", "pentolite" or a perchlorate based explosive such as that ~escri~ed in RSA patent 92/a660.

The container may, in a preferred embo~iment, be bottle-like, in that it has a neck portion through whi~h tbe detonator is in~erted into the explosive .material contained ~herein. Conveniently, ~he securing mem`oer may then be in the form of a cap which is secured to ~he neck portion. For this purpose, the securing me~er and the neck portion may have complementary securing formations, such as comple~entary screw-threads or a bayonet and complementary slot.

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-~ 2~47~2:1 ~ 5 The container may furthermore have a ~ubstancially globe shaped bo~y portion. lt may thus be rounded at its botto~ end, (ie. the end re~ote from the neck portion) and tapered from above.

The con~ainer may be of a suitable synthetlc plastics material and may in particular, be P~T. ~ -The explosive material may be inserted in the container in any suitable manner Thus, a6 is k~own in the art, the explosive material may be supplied in a fluid form, either a liquid or a paste, which 16 then charged inta the contain~r and allo~ed to set or dry.
A socket may be formed in the explosive material whilst -~
this occurs, in which the detonator is recei~able~ The ~
soc~et may extend about two thirds inco the container. `-~`
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15A6 indicated above, the container may be -botcle-like and filled ~hrough its neck portion. ~`
Instead, che bottom of the oontainer may be open and the container may be filled with the explosive material through this opening, with the neck portion bein~
20t~e~porarlly closed.
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The container may also have a f~ange, on the `
~: neck portlon, close to its mouth. Thi6 flange may al~o ¦ be used to ~ecure the signal transmit~er to the ~ ~
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2147~21 container, ~ith the slgnal transmitter being wound around the flange and suitably knotted to ~ecure it to the container.
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If the 6ecuring member i~ in the form of a cap, it may haYe an aperture through which the signal tran~mitter passe~. The cap may be fa~t with the signal transmitter or it may be slidable there along. If it is ~ast ~ith the signal transmitter this may be achieved by mean~ of a gripping element. On the other hand, if ~he cap is 61idable along the signal transmitter a movemen~
limi.ting mean6 may be provided ~or limiting movement of the cap along the 6ignal transmitter towards the detonator, at a suitable position close to the detonacor.

In l~s mo6t simple form, this may ~e achieved by the maki~g of a knot in the signal transmitter close to the detonator or by placing the aperture ln an o~f-set position in the csp so that, when the detonator ~s insert~d inCo the boo~ter and the cap secured to the 20 container thereof, a kink i6 formed in the ~ignal transmlt~er which mechanically locks the signal transmitcer to the cap.
i In~tead, the movement limiting ~eans may be effected in a more sophisticated manner and may utilise a gui~able ~rticle sDch as a fsrruls which is deiormed ~21~7~2~

onto ~he signal transmitter and is clamped chereto at a sultable position thereo~. Stlll further, the movement limuting means may be in the form of a plug which is slidable along the signal transmitter but iB deformed : ::
5into clamping engagement therewith. The plug may be ; ~.:
defonmed when the cap is secured to the neck portion of the ~ontainer or prlor thereto. Further, the ?lug may : ~:
be separate to or integral with the cap. still furcher, .~. :
: .. :
the cap may be of a one-piece construction or may be in two or more parts.
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The invention is now described, ~y way of -~ examples, with reference to the accompanying drawings, I in which~
Figure 1 6hows a ~irst embodiment of a ~la6ting componen~ in accordance with ~he invention;
Figure 2 shows a first embodimènt of a booster in ;-; -accordance with the invention, which is, in use, used `
together with the bla~ting component o~ Figure 1;
Figure 3 ~ho~ a ~econd embodimen~ ~f a blasting : :
20 componen~ in acco~dan~e with the invention; ~ "~
Figure 4 6hows a ~econd embodiment of a booster in ~:
accordance with the invention, whlch i~ used together , ~ith the 'olasting component sho~n in Figure 3;
Figure 5 shows a thlrd embodiment of a blasting 25component in accordan~e with the invention;
Figure 6 show~ a~ underneath plan view of a plug forming part of the bla6ting componen~ of Figure 5;

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Figure 7 6hows a third e~bodlment of a boost~r in accordance with the inventlon, which is use~ with the blas~ing component 3hown in Figure 5;
Figure 8 shows a fourth embodi~ent of a bla~ting 5companent in accor~ance with the inventioni Figure 9 shows an underneath plan view of the cap which forms part of the blaisting component shown in Figure B, Figure 10 shows a fourth embodiment of a boo6ter in lOaccordance with the ~nvencion which ls used together ~ith ~he blasting co~ponent shown in Figure R;
Figure 11 shows a fifth embodiment of a bla~ting component in accordance with the invention, in a partly . exploded view;
15Figure 12 show6 an underneach plan ~lew o~ one part of the t~o part cap u~ed with the blasting component of Figure 11;
Flgure 13 6hows a fifth em~odiment of a blasting component ln accordance with the invention which is used 20together with the blasting componenc shown in Figure lli Figure 14 ~hows an exploslve component in accoxdancs wi th the invention;
Figure 15 5~0WS a sixth e~bodiment of a blasting component in accordance with the invention anà a slx~h 25embodiment of a booster in accordance with the invention, maced toyether; and Figure 16 shows a seventh embodiment of a blasting componen~ in accordance with the invention and a seventh ; .

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g embodiment of a booster ln accordance with the inventlon, al60 mate~ together.

Re~erring to Figure 1, parc of a blasting component in accor~ance with the invention i8 designated generally by reference numeral 10. The compo~ent 10 comprise6 an electronic deto~ator 12 with a ~ult~-cored cable 14 thst is fairly, strong bei~g able to withstand a tensile force of 430 ~. It will be appreciated that only a portion of the cable 1~ 1s shown.
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A ~errule 15 iB at~ached to the cable 14 clo6e -. .
to the deconator 12.
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A cap 16 havlny a roof 18 and a skirt 20 i8 slidably mounted on the cable 14 by ~eans of an openiny in ~he roof 18. The skirt 20 has an internal screw thrsad 22. It will be understood chat Ghe ape~ture in the roof 18 iB 3ufflciently mall to foul with the ferrule 15, such that the ferrule 15 acts as a stop.
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Referring now to ~i~ure 2 a boo6ter in accordance with the inventio~ esigna~ed generally by refere~ce numeral 2~. The ~ooster 24 co~prises a container 26 which is ~lled with a suitable explosives material 28, such as pentolite. The container 26 is of a suitable synthetic plastics material such as P~T.

` 2~47~21 ` .
' - 10 -It will be seen that the container 26 i~
bottle-like, ha~ing a neck portion 30 and a body portion 32. The body portion 32 is globe-like having a ~ru~to-conical portion 34 extending downwardly from the neck portion 30, a fur~her cy]indrical portion 36 an~ a rounded bo~tom portion 38. ~he hottom portion 38 ha~ an opening 40. The conealner 26 further has a ~lange 42 at th~ junction be~ween the nec~ por~ion 30 and the frusto-conical portion 34. The neck portion 30 has an external screw threa~ 44 whlch is complementary to and mate6 with the internal 6crew thread 22 of che cap 16.

It will also be noted that a siocke~ 46 i~
: formed in the explosive material Z8 at the mouth o~ the neck portion 30.

15The container 26 is blow moulded in a ~uitable mould and the opening 40 iE thereafter formed in ~he bottom portion 38. The explosive material 28 is . supplied ln a fluid for~, eicher a~ a liquid or a paste.
A 6uitable closure (not shown) is utilised to close the 20mouth of the neck portion 30. Thi~ cloEure has a spiyo~
wh~ch extend~ into the container 26. The explosi~e ma~erial 28 i9 then charged into the container 26 through ~he opening 40 and allowed to set or dry. Once the explosive ~aterial 28 has ~olidified the closure is 25remo~ed with the spigot thereof forming the socket 46.
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The bla~ting componenc 10 and the boo~ter 24 Bre ~anufactured separately and tran~ported and ~tored apart from one another. Immediately prior ~o use the detonator 12 iB pushed into the socket 46 and she cap 16 ¦ 5 secured to the neck por~ion 30 by means of the ¦ complementary threads 2~ and 44. The detonator 12 i6retaine~ within the ~ocket 46 in the booster 24 by means of the ferrule 15 and the cap 16. Thus, the booster 24 can be lowered and raised in a blasthole by ~eans o~ ~he cable 14, even if the blasthole has been charged with explosive.

¦ Referring to Figure 3 a further example of a bla~ting component ln accordance wieh the invention i6 de~ignated generally by refe ence numeral SO~ ~his blasting ~omponent 50 19 simllar to the blasting component 10 of Fig~r~ 1 in that it has an electronic detonato~ 12, a cable I4 and a cap 16~ Howe~er, instead o~ using the ferrule 15 a knot 52 iB tied in the cable 14 to limit ~ovement of the cable 14 with respect to the cap 16~
.
Referring to Figure 4, a ~urcher booster~54 is shown~ The booster 5~ is similar to the booster 24 shown ln Figur~ 2 except that the container 26 does not have an opening in iCs bottom portion 38. wlth this embodiment, the explo~ive material 28 i5 charged through the neck portion 3~. A sui~able ~or~ing tool (not . .~ ~
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5 2 t 6hown~ i6 used to form ~he socket 46 in the explo~i~e ; material Z8. Further, the explosi~e material 28 iB not filled to the ~Op of the neck portion 30 in order to pro~ide a space 56 for t~e knot 52.

The detonating componant So and the boo~ter 54 are used in a simllar msnner to the eomponent 10 and booster 24 of Figures 1 and 2.

Referring to Figure 5, a furcher blasting component 58 ls shown. ~his component s8 i6 again similar to the component 1~ of ~igure 1 in that it lncludes an eleccronic detonator 12, a cable 14 and a cap 16. However, instead of using the ferrule 15 a plug 60 is used. The plug 60 is frusto-conical and has an access slot 62 leading co a central psssage 64, as shown more clearly in Figure 6. The plug 60 is of a suitable resilient material and che cable 14 is pu6hed through the 810t 60 ~o occupy the pa~sage 6g.

The booster which is used with the blasting component 58 is shown in Figure 7 and ls de~ignated generally by reference numersl 66. The boo~ter 66 is similar to the booster 54 shown in Figure 4 except tha~
the bla~cing material 28 is filled co che top of ~he neck portion 30 and the socket 46 has a fru~to-conical entrance 68 which comple~ents the plug 60.

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Thus, ln use, when the detonator 12 is in6erted in t:~e socket 46 the plug 60 is located in the en~rance 68 a~d, as the cap 16 is tightened on the nec~ -portio~ 30 th~ plug 60 i~ compre6sed, thereby gripping ~he cable 14.
, ::' Refarring ~urther ~o Flgure~ 8, 9 and 10, a ~ ~-, : , further blast ng component 70 16 shown. Thi3 blasting component 70 ~ si~ilar to the blas~lng component 58 ~hown in Fi~re 5 excep~ that lt doe~ no~ ha~e a 10separate plug 60. Instead, the cay 16 ha6 an integral gripping par~ 72 with internal teeth and a frusto~
conical exce~nal shape. A~ seen in Figure 9, the gripping part 72 iQ formed by four fingers 74 which extend lnwardly ~rom ~he roof 18.

15The blasclng component ~0 i~ used with a booster 76 a3 shown in Figure 10. The booster 76 i6 ~ubsta~tially the same as the booster 66 shown in Fiyure 7 except that it does not ha~e a ~lange 42~ Further, the bla6ting ~omponent 70 and booster 76 a~e used in a similar manne- to the blasting component 58 and booster 66 shown in Figures S and 7.

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Refsrring now to Figures 11, 12 ar.d 13 a - :

further embo~iment of a blastlng component 78 is shown.

The blastin~ component 78 is again 5imllar to the ~lasti~g c3m~nent 70 of Figure ~. Ho~ever, w~t:~ this , ':' ~'~
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21~7a21 component 78, the cap 16 has two parts, a body part 80 and a locking pare 82. The body part 80 is similar to the cap 16 shown in ~igure 8 and has, ln addition to the fingers 74 furcher yripping formations 84 which project upwardly ~ro~ a ba6e 86 on top of the roof 18. The grlpping ~ormation~ 34 are also externally frusto-conical. The base 86 has an external screw-thread 88.
~he locking part 82 fits over the gripping formations 84 and the ba6e 86 and i8 configured in a complementary manner. The loc~ing part 82 accordingly has a screw thread 90 ~hich engages with the screw thread 88. When the locking par~ 82 is screwed onto the base a6 it compresses the gripping ~ormations 34 into gripping engagement wich the cable 14.

The blasting co~ponent 78 i5 used with the booster 92 shown in Figure 13. The booster 92 has a container 26 that is the same as that of the booster 2 qhown in Flgure 2. However, che socket 46 is formed with a tapered entrance 6B as with the boo~ter 66 o~
Figure 7. In use, the detonator 12 is inserted in the socket 46 a~d the body part 80 ls secur&d to the neck portion 30 o~ ehe ~ontainer 26. The locking part 82 i5 then screwed onto the base 88 thereby deforming the gripping formations 34 into locking engagemen; with the cable 14.

It will be appreciated tha~ the various ~` 214732:1 :
, -15 ~ ::
blas~lng components together wlth their a6~0ciate~ ~ :
boo~ters, when they are mated together, constitute explo3ive components as di~cussed above.
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Re~erring further to Figure 1~ an explosive co~ponent in accordance ~ith the invention i~ ~esignated :-:
generally by reference numeral 96. The exploQive co~ponent 62 compri~es a boo~ter 98 which has a rigid I container fille~ with explosive material similar to the ! booster 24, 54, 66 and 92. In particular, the container of the booster 98 has the flangs 42. The explosive component 96 also ha6 an electronic detonator 100 which i6 located in the socket 46 in the explosive material 28. The detonator loo ha6 a cable 102. Howe~er, wlth~ ~
~hi~ explosive component 96 the cable 102 i5 not secured ~:.
to the container 98 by mean~ of a cap as is ~he case ~-with che embodiments described a~ove. Wich this embodi~ent the cable io2 is wound around the flange 42 and ~uitably knotted to secure it to the booster 9~

Re~erring further to Figure 15 a ~urther example of an explosi~e component 106 is sho~n. This blasting compo~nt lo~ utilises a blasting co~ponent 108 which comp~ises an electronic de~onaeo~ 12 having a cable 1~ together uich a cap 16 which has an o~-se~
aperture in its roo~ 18. The booster llO has a con~ainer 26 ~hich cQntains explosi~e material 29 in a ;-`
Eiimilar manner to the boosters de3cribed earlier with '' -: ' . '' ':
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- 16 ~
the explosive ma~erial 28 having a central socket 46.
the soc~et 46 is centrally positioned and the apert~re in thP roof 18 is off-6et, when the cap 16 i6 scre~ed onto the ~eck portion 30 a kink 112 i5 forme~ ln 5the cable 1~ thereby locking the cable 14 with respect ¦ to the cap 16.

Referrlng finally to Figure 16, a ~urther em~odiment 116 of an explosive component i~ shown. Thi~
explosive component 116 i9 sirnilar to the explosive 10component 106 6hown in Figure 15 except that ~he socket 6 i6 off-set and the aperture in the roof 18 o~ the cap 16 i8 centrally po6itioned. Thus, a kink 118 iB also ~ormed which 6erves to lock the cable 14 ~ith respece to the cap 16.

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Claims (33)

1. A blasting component, which comprises a detonator insertable in a booster;
a signal transmitter extending from the detonator;
and a securing member for securing the signal transmitter to the booster.

2. The blasting component as claimed in Claim 1, in which the signal transmitter is a multi-cored cable.

3. The blasting component as claimed in Claim 1 or 2, in which the securing member is a cap which is engageable with the booster and has an aperture through which the signal transmitter passes.

4. The blasting component as claimed in Claim 3, in which the cap is fast with the signal transmitter.

5. The blasting component as claimed in Claim 3, in which the cap is slidable along the signal transmitter, and which includes a movement limiting means for limiting relative movement of the cap and the signal transmitter.

6. The blasting component as claimed in Claim 5, in which the movement limiting means comprises a knot in the signal transmitter.

7. The blasting component as claimed in claim 5, in which the movement limiting means comprises a ferrule that is clamped to the signal transmitter.

8. The blasting component as claimed in Claim 5, in which the movement limiting means comprises a deformable plug that is slidably located on the signal transmitter and, in use, deforms into clamping engagement with the signal transmitter upon engagement of the cap with the booster.

9. The blasting component as claimed in Claim 8, in which the plug is part of the cap.

10. The blasting component as claimed in Claim 3, in which the aperture is off-set in the cap.

11. The blasting component as claimed in Claim 5, in which the cap has a deformable gripping component engageable with the signal transmitter, and a deforming component for deforming the gripping component.

12. A booster which comprises a container which is of a rigid material;
a suitable explosive material contained within the container;

the container having an opening through which a detonator having a signal transmitter may be inserted into the explosive material; and with the container having a securing formation by means of which the signal transmitter of the detonator may be secured to the container.

13. The booster as claimed in Claim 12, in which the explosive material is pentolite.

14. The booster as claimed in Claim 12, in which the container is bottle-like having a neck portion and a body portion.

15. The booster as claimed in Claim 14, in which the neck portion has a securing formation whereby a cap may be engaged with the container.

16. The booster as claimed in Claim 14, in which the body portion is rounded at its bottom end and tapers towards the neck portion.

17. The booster as claimed in Claim 14, in which the neck portion has a flange whereby the signal transmitter may be secured to the container.

18. The booster as claimed in any one of Claims 12 to 17, in which the explosive material defines a socket that extends through a major part of the container and in which the detonator is receivable.

19. The booster as claimed in Claim 18, in which the socket is centrally located in the container.

20. The booster as claimed in Claim 18, in which the socket is non-centrally located in the container.

21. The booster as claimed in Claim 18, in which the socket has a frusto-conical entrance,

22. The booster as claimed in Claim 14, in which the body portion is open at its bottom end.

23. An explosive component which includes a booster comprising a rigid container that is filled with an explosive material;
a detonator located in the explosive material; and a signal transmitter of the detonator secured to the container.

24. An explosive component which comprises a booster as claimed in any one of Claims 12 to 22 in combination with a blasting component as claimed in any one of Claims 1 to 11, the detonator of the blasting component being in the explosive material and the securing member securing the signal transmitter to the container.

25. An explosive component which comprises a booster as claimed in Claim 14 in combination with a detonator having a signal transmitter, the detonator being in the explosive material and the signal transmitter being secured to the container by means of the flange thereof.

26. A method of blasting, which includes mating a detonator with a booster immediately prior to insertion of the booster into a blasthole.

27. The method claimed in Claim 26, which includes securing a signal transmitter of the detonator to a container of the booster.

28. The method claimed in Claim 27, which includes suspending the booster in the blasthole by means of the signal transmitter whilst the blasthole is charged with explosive.

29. The method claimed in Claim 27, which includes lowering the booster into a blasthole by means of the signal transmitter, charging explosive into the blasthole and lifting the booster a short distance through the explosive by means of the signal transmitter.

30. A blasting component substantially as described in the specification with reference to the accompanying drawings.

31. A booster substantially as described in the specification with reference to the accompanying drawings.

32. An explosive component substantially as described in the specification with reference to the accompanying drawings.

33. A method of blasting substantially as described in the specification with reference to the accompanying drawings.