Packaging system for detonating cords for X-ray examination and safe shipping

#The invention relates to packaging for a detonating cord and a method of examining a detonating cord in its packaging.

#Detonating cords are used to fire shaped charge perforators in perforating guns in the oil and natural gas industry. To ensure error-free initiation of charges, a defect-free detonating cord is needed. Incomplete detonation caused by inadequate filling of the detonating cord with explosive material may in particular lead to costly delays.

#To enable these detonating cords to be shipped by sea, land or air, special packaging is required, the requirements for which are regulated by law. Packaging is described, for example in EP 0 382 615 B1, U.S. Pat. No. 4,586,602 or U.S. Pat. No. 4,817,787.

#The invention is explained in more detail below with reference to two Figures.

#FIG. 1 shows an X-ray image of a spiral detonating cord in its packaging.

#FIG. 2 shows a packaging system according to the invention for a detonating cord.

#FIG. 2 shows a packaging system according to the invention for a detonating cord 1. The detonating cord 1 is wound as a flat spiral, the two ends being provided with an end cap 4. The base plate 2 of the packaging may consist, for example, of paperboard, wood or polystyrene. In the embodiment illustrated here, the detonating cord 1 is attached to the base plate 2 via a vacuum bag 3. This means that the detonating cord 1 is sealed in a plastics bag, which is in turn attached to the base plate 2. One lap of detonating cord 1 is passed perpendicularly over the flat-wound spiral.

#Adhesive strips 5 adhering in the shape of a cross to the detonating cord 1 serve to fix the detonating cord 1 prior to sealing in the vacuum bag 3. The individual laps of the spirally wound detonating cord 1 are arranged at a given spacing from one another, so that, in the event of misfiring of the detonating cord 1, the adjacent lap is destroyed without crossover firing taking place. Crossover firing means that the adjacent lap is ignited and the ignition process passed on to the remaining laps. In FIG. 2, the space is produced by a spacing cord 8 extending in parallel.

#Reference numeral 6 indicates the image area of an X-ray installation, wherein the entire detonating cord 1 is advantageously X-rayed at once. The X-ray image is preferably taken at a right angle to the plane of the spiral detonating cord. If a booster is connected to the detonating cord 1, the wad gaps between booster and detonating cord 1 may likewise be inspected by X-ray image.