CZ156794A3 - Slow-burning delay pyrotechnic mixture for pressureless system of non-electrical blasting cap - Google Patents

Abstract

The invention concerns a slow-burning delay charge with a short interval of delay and a timing accuracy from 0 to 10 seconds utilisable for pressure-less systems of non-electrical detonators activated by detonation tubes of the NONEL type. The slow-burning delay charge contains 20 to 50% by weight of barium chromate, 19 to 50% by weight of lead chromate, 20 to 60% by weight of manganese and from 1 to 7 % by weight of zirconium, which eliminates problematic conditions of ignition and creates optimum energy ratios for regular combustion of the delay charge even under extreme temperature conditions and the effects caused by natural aging of the mixture.

Description

Flame-retardant delay component for non-pressurized non-electric systems.

Technical field

The invention relates to a delaying composition for non-pressurized, open-ended, longer-term non-electric detonator systems activated by an NCNEL (SHOCK TUBE) detonation tube for delaying an explosion from 0 to 10 seconds with a delay time interval of 200 to 500 ms. The delayed component pressed into the delay element ensures the time-delayed transfer of the direct or possibly amplified thermal impulse of the NCNEL tube to the explosive part of the detonator. The entire pyrotechnic delayed system shall ensure a minimum scattering of the detonator timing within the range of the length of the bar of the delay composition ode 2 to 40 mm.

BACKGROUND OF THE INVENTION

The timing accuracy of the non-electric detonator in the range of 0 to 10 seconds with a time interval of 200 to 500 ms is decisively influenced by the design and technology of the delay composition. The pressure manifestations of its combustion are dissipated by the detonation tube of the non-electric detonator and therefore the combustion takes place in a completely open system, which is very disadvantageous to achieve reliable ignition and regularity of the delay composition, which has a negative effect on timing accuracy. The quality of the delay composition in terms of reliable ignition and the regularity of the burning time is decisive for the timing accuracy of the non-electric detonator in the range 0 to 10 seconds and is characterized by a statistically standard deviation relative to the non-electric timing of the non-electric detonator.

the time interval of 500 ms is realized in 12 time stages up to a nominal delay of 6 00.0 ms with a standard deviation of up to 80 ms. Above 6,000 ms, an irregular time interval of 600 to 900 ms is achieved with a standard deviation greater than 1Ό0 ms.

To achieve. Delay times in the time domain of up to 10 seconds use delaying compounds consisting of flammable substances, oxidizers and other flocculants such as fire rate moderators and binders. In general, Mo, W, Sb, Μη, B, S, Si, Fte, Cr, Mn, Si, Fe, Mn, Cr and others are used as combustibles. Barium and lead chromates, potassium perchlorate, minium, iron oxide, potassium permanganate and others are mostly used as oxidants. The auxiliaries used are flame-retardant moderators such as antimony sulphates, iron oxide, titanium dioxide, quartzite and binders such as polyvinyl alcohol, dextrin, bentonite, natural and synthetic resins and others.

2. SUMMARY OF THE INVENTION

The elimination of the negative impact of an open detonator system on reliable ignition and regular combustion of the delay time column in the variable length delay element housing is achieved by solving the lead and barium chromate delaying solution as oxidants, manganese as flammable and zirconium, Delay of the detonation tube or amplification pyrotechnic element, which by its characteristics ensures regular burning of this delayed composition in the optimal energy mode of combustion in the design of non-electric detonators, characterized by high accuracy of burning time within 10 seconds with minimal static standard deviation from delay, wherein a delay time in the range of 0 to 10 seconds with a time interval of 200 to 500 ms is achieved by the optimum ratio of said components of this delaying composition with a zirconium content of 1 to 7%, the zirconium content also having a beneficial effect on function reliability in the temperature range from -40 to + 65 ° C and eliminating the burning changes caused by natural aging of the style, artificially modeled by a temperature exposure of 65 ° C for 30 days.

DETAILED DESCRIPTION OF THE INVENTION

Flame-retardant delay component for non-pressure non-electric detonator systems - is pressed into the delay element of the open non-electric detonator system and is ignited by the thermal pulse of the nonet detonation tube. Directly or by means of a transmission element with a spark ignition composition - is a mixture of bismuth, lead, manganese and zirconium in the following percentage by weight:

Lead chromate: 27%

Chromate Chromate: 36%

Manganese:. 34%

Zirconium: 3% •

Said delaying composition, pressed into a variable-length delayer housing and applied in a non-electric detonator construction system, provides the creation of 20 time stages with a delay time of 500 ms in the delay range from 0 to 10 seconds.

The results of the 10 (5,000 ms) and 18 (9,000 ms) delay times in the steel casing of the 20 mm and 40 mm styli column are shown in Tables 1 and 2.

Table 1

Style column height: 20 mm

Nominal delay Achieved delay Standard deviation achieved (ms) (ms) (ms) 5 000 5 035 43 Table 2 Column height: 40 mm Nominal delay Achieved delay Standard deviation achieved (ms) (ms) (ms) 9 000 8 978 75 Industrial applicability

The flame-retardant delay component for non-pressurized non-electric detonator systems can be used in a non-electric detonator delay element activated by a NONEL detonation tube with a delay time of 200 to 500 ms in the delay time range of 0 to 10 seconds. Advantageously, the high timing accuracy of the zirconium-containing delay composition designed according to the invention can be utilized.

Claims (2)

A pan-burn delay component for non-pressure non-electric detonator systems with a delay time interval of from 200 to 500 ms, characterized in that the high timing accuracy in the range of 0 to 10 seconds is ensured by the delay composition of barium and lead chromate, manganese and zirconium in the stated weight percent range of individual components - barium chromate ................ 10λϊ 50% j lead granulated ............... 10ce 50 % (manganese ............................. 20 As 60% _f Zirconium ...................... 1 7%. 7omAtnhor iW apožgl ovac ·? 2. A method according to claim 1, wherein the timing accuracy is assured in the temperature range from -40 [deg.] To + 65 [deg.] C.