Abstract:
A detonating device principally intended for detonating an explosive charge in a well or borehole, and of the type which is actuated by pulling upwardly on a non-electrical line also used to lower the device into position. The device includes self-contained time-delay circuitry which requires a sustained mechanical actuating pull on the line for some predetermined time before an attempt is made to detonate the explosive. The circuitry includes a command switch actuated by pulling on the line, and a safety switch which must be closed before the command switch is closed, either manually or by hydrostatic pressure in the borehole. The circuitry locks in a safe condition if the command switch is closed first, or if one attempt has been made to fire the explosive, whether successful or not, thus allowing removal or repositioning of the device with complete safety.
Abstract:
There is disclosed a single wire multiple shot selective fire perforating gun for piercing oil field tubular goods, typically during the process of completing an oil or gas well. A switch in the gun electrically isolates an associated blasting cap and short circuits the terminals thereof until the associated blasting cap and perforating element are armed. A plurality of blasting cap-perforating element assemblages are vertically disposed on the tool with the detonation of one perforating element arming the next adjacent blasting cap.
Abstract:
An apparatus for testing the energy output of a blasting machine used for detonating electro-explosive devices to determine if the blasting machine will supply sufficient energy to detonate the electro-explosive devices. The tester is capable of determining within plus or minus one Joule the output of a 25 Joule blasting machine. The energy tester includes go and no-go indicator lights to inform the operator of the blasting machine whether or not he has sufficient energy.
Abstract:
A remote control circuit and apparatus for exploding explosives. Electric power generated at a resonance circuit when it is tuned to a control electromagnetic field is used to charge an ignition condenser. Provision is made for a control circuit including a controlled rectifier called a triac. The control circuit is adapted to generate a starting pulse at an instant when the control electromagnetic field is extinguished. The starting pulse serves to make the controlled rectifier conductive and hence discharge the ignition condenser through a detonator, thereby initiating it and exploding blasting explosives used to break rock and other solid material.
Abstract:
Apparatus is provided for testing individually a plurality of blasting caps and for detonating such caps simultaneously. A plurality of double-pole, double-throw switches to serve to connect the blasting caps selectively to a circuit continuity meter or to a detonating device.
Abstract:
This is an electrical circuit for time limiting the application of current to an external load. A charging network is fed by alternating current having a capacitor charged through resistance means and a diode when a switching element is positioned conductive between the capacitor and resistance means. A pulsing network is fed by the alternating current which network has a transformer, resistance means, diode and Zener diode providing a pulse to a first silicon controlled rectifier on the half-cycle when the switching element is positioned nonconductive between the capacitor and the resistance means and is positioned conductive between the capacitor and the first rectifier. A second silicon controlled rectifier receives the potential of the capacitor through the first rectifier in its conducting state which in turn allows the second rectifier to conduct and thus permit the capacitor to discharge through said second rectifier to the external load to be controlled. This circuit is particularly adapted to the firing of electrically activated delay blasting caps without arcing when using high voltage.