• Explosives and Blasting
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• v.27 no.1
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• pp.1-6
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• 2009

The strainer can be clogged by dusts in a well. As a result, the permeability of a strainer is extremely reduced. This paper is intended to propose a cleaning method of strainer using blasting pressure of the detonating cords and to examine the applicability of this method. The pressure range that was not expected to affect the strainer was estimated. Test results of $3,000\;kg/cm^2$ pressure with a diameter of 12 cm without damage to the strainer was found to be appropriate. The mortar attached to the strainer was almost completely eliminated.

• Proceedings of the KSEEG Conference
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• 2000.04b
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• pp.215-218
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• 2000

• Proceedings of the KSEEG Conference
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• 1999.04a
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• pp.223-225
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• 1999

• Explosives and Blasting
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• v.36 no.3
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• pp.29-38
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• 2018

With the recent industrial developments and economic development nationally, there has been a rapidly increasing demand for the use of underground space as locations for establishing social infrastructure and various convenience facilities. In this study, a mist-control system was developed to reduce the generation of dust in underground blasting. To enhance the dust-reduction effect, a guiding device was developed which is capable of adjusting the direction of the spray toward's the blasting face of mine or tunnel. A numerical analysis was performed by using the AUTODYN software, and results were compared with those published in basic experiments. To verify the mist-diffusion effect according to the position of explosives in a water bag, numerical analyses were conducted for the following cases: Explosives were set in the middle, and in the bottom of the water bag. The optimum condition was external detonation and center charge. The mist particle size from the result was suitable for the reduction of dust after blasting in underground mine and tunnel.

• Explosives and Blasting
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• v.37 no.4
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• pp.17-25
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• 2019

The method to remove the head of the cast-in-place pile using the detonating cord and horizontal separation plate was proposed in this paper. Plain concrete block was fabricated. Through the blasting test of the concrete block, the charge weight and the burden required for cutting the pile head were identified. The degree of damage of concrete blocks after cutting the head was checked using AUTODYN 2D. As a result of the experiment, it was found that the concrete block was cut using the 10 g/m detonating cord and horizontal separation plate, and the directional cutting of the block using the horizontal separation plate and the block damage caused by the detonating cord were reduced.

• Defense and Technology
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• no.2 s.276
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• pp.30-39
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• 2002

화공기술이란 연소와 폭발성을 갖는 단일 또는 복합 물질을 기제로 하여 제품을 사용 목적에 맞도록 제조와 응용하는 기술을 의미하며, 화약의 에너지 물질로서 제조된 다양한 제품을 화공품(Pyrotechnics)이라고 한다. 우리 주변에서 흔히 볼 수 있는 것은 산업용으로 성냥, 딱총약, 엽총화약, 연화, 광산용의 도화선, 도폭선, 각종 뇌관류 등이 있고, 군용으로는 발사화기와 로케트 추진기관의 점화계열, 탄두/탄약의 폭발계열, 신호탄, 연막, 조명탄 등을 들 수 있다.

• Tunnel and Underground Space
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• v.25 no.1
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• pp.46-55
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• 2015

A water tube with detonating cord was devised to control the blast dust. Water diffusion experiments with different detonating cord positions were conducted during the series of experiments to optimize the design parameters of the tube. Images from high speed camera were analyzed to evaluate the results. AUTODYN program was adopted to simulate the diffusion process of water and compared with the images. Diffusion of water shows cross flow in case of external charge while the internal case shows radial flow. A bubble ring was formed during the numerical analysis of internal charge case as occurred in underwater blast. An additional bubble ring was formed by the reflection pressure from the ground. And the Weber number was determined as sufficient for spray atomization performance of the water tube.

• Tunnel and Underground Space
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• v.17 no.4
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• pp.295-300
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• 2007

A method using detonating cord was suggested to control the blasting source for scaled model test. Blasting of 5 concrete block was carried out to verify the method. It was proved that blasting power can be controlled by suggested method. It seemed to be reasonable to use the reduction ratio based on the explosion heat.

• Explosives and Blasting
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• v.18 no.3
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• pp.49-58
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• 2000

본 논문은 양면발파에 의한 채석기술에서 주로 양면발파 장약패턴 및 다이아몬드 와이어쏘절삭기술에 관한 내용을 중심으로, 현재 각 석재광산에서 시행하고 있는 채석기술과 연구소 에서 시행한 현장 시험발파 결과를 기술한 것이다. 첫째, DA석재광산에서는 제트버너를 이용하여 자유면을 형성하고, 일면발파법과 양면발파법의 작업시간을 비교한 결과 양면 발파할 때에 37%이상의 작업시간 절약효과가 있었으며, 인원은 36%이상의 감소효과가 있었다.둘째, DH석재광산에서는 다이아몬드 와이어쏘를 이용하여 자유면을 형성하고 양면발파 작 업시간과 타 광산에서 일반적으로 사용하고 있는 제트버너에 의한 양면발파 작업시간을 비교하였을 때에 21%이상의 절감효과가 있었고, 작업인원도 21%이상의 감소효과가 있었다. 다이아몬드 와이어쏘를 이용하여 양측면에 자유면을 형성하고 양면 발파하는 채석기술은 소음 및 분진에 의한 환경공해를 방지할 수 있었으며, 작업공정 및 경제성 면에서도 매우 유 리하나 실패시 다른 채석기술에 비해 모암의 손상으로 인한 경제적 손실이 커질 수 있다는 단점도 있으므로 정밀한 발파설계 및 기술이 필요하다.

• Explosives and Blasting
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• v.17 no.4
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• pp.32-50
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• 1999

This study deals with interface charactristics of tube and tubesheet of the nuclear steam generator by the explosive expansion in order to take advantage of optimum expansion ratio, pull-out strength and leakage tightness and improvement of the resisitance on the stress corrosion cracking for low residual stress. The paper also show the relationship between roll, hydraulic and explosive expansion. The results obtain are as follows (1) Because of the explosive bonding is to use the high speed pressure and energy by the explosive, workability is good, bonding region is homogenous (2) Expansion ratio is 2.7%, Pull-out strength 850kg, Leakage strength $500kg/cm^2$. Clearance gap is 10~30mm in case of explosive expansion and interface structure of the tube and tubesheet is optimum condition. (3) As the transition region of the explosive expansion is inactive, the resistance of the stress corrosion cracking is increases 30~40% compare to the roll and hydraulic expansion.