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At present I am retired and spending my time mostly on fishing and photography. I bought my first SLR way back in 1982. It was a Minolta XG1. My last film camera was the Maxxum 9000. When the fantastic Sony Alpha 100 was launched, I changed over to the digital system. My Alpha 580 was acquired followed closely by my Alpha 77.

My main interest in photography is lifestyles, sports, sceneries, nature, birds and macro shots. Lately, I have spend more time on bird and nature shooting. As a regular contributer to some fishing magazines, I shoot quite a lot of photographs of anglers too....hence my photography blog is named 'SHOOT THE HOOKER'.



Having grown up near the confluence of two, the Kangsar and the Perak Rivers, it is not surprising that one of my main interest is fishing. My younger days were spent swimming and fishing.... with a bamboo pole, line and small hooks.Now while fishing, my friends and I do take a lot of photographs of anglers in action. The anglers must be careful so as not to accidentally hook on to a photographer. So I think as a reminder, I would like to name my fishing blog as 'HOOK THE SHOOTER'.

Tuesday, August 14, 2012

Rock Blasting.

Recently I was taken to some rock blasting operation by my friends who is an expert rock blaster. At the quarries that we went to I was shown the different steps, procedures and apparatus used for blasting. I would like to share here the photographs of the whole operation.



1.   Hydraulic crawler drills were used to bore holes of about 50ft-60ft into the rocks. Drill holes were normally 18 meters deep (depending on the bench design) and 89mm in diameter.








2.   The pink coloured cast booster connected to the pink coloured shock tube.



3.  Pink coloured shock tubes with the detonators (for starting the explosion) were then inserted into the cast boosters (dynamites). These were then lowered into the drilled holes in the rock. The end of the shock tube is the detonator.









4.   A mixture of oxidising agents are then pumped into the hole on top of the cast boosters. This bulk emulsion as they are called are used for the secondary explosion. The secondary explosion creates a rapid expension of gas which breaks up the rock.
A rough formula for the amount of bulk emulsion used is 0.4 -0.5 kg per cubic meter of rock. When the cast booster explode, it will create detonation speed that exceed the speed of sound so that the bulk emulsion can be detonated.






5.   The brown coloured bulk emulsion.








6.   Red coloured surface delay detonator connects the pink shock tubes from hole to hole. Delay time is 25 milliseconds.








7.   Black coloured surface detonator together with the yellow shock tube are for row to row detonation.  Delay time is 67 milliseconds.






8.   Blasting site is cleared of people. Alarm is sounded and the blast master made his round to make sure all is cleared before lighting the fuse. Safety fuse burns at 1 second per cm. Normally 4 minutes are needed for the person lighting the fuse to move to a safe distance.





9.   Beginning of the detonations.









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12.








13.   Completion of blasting.








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