Fluid desensitised safe-arm detonator assembly - for oil well perforating gun assembly, involves rotation of housings to obtain necessary condition

摘要

A detonating assembly comprises the housing members which are axially aligned with each other and have respective bores for a detonator and a booster. The housing members are movable about an axial shaft from a safe position with the bores non-aligned and an armed position in which the bores are aligned. A safety pin extends into a cut out portion in one of the housing members and covers one end of the booster bore when the housing members are rotated to a safe posn. Used as safe/arm detonator assembly for an oil well perforating gun. The gun assembly may be transported with the detonator assembly in the safe position and rotated to the armed position at the well site without disassembling the gun assembly. The safety pin covers and protects the booster from accidental detonation when the detonator assembly is in the safe position. The movement between safe and armed positions does not disturb the seal between the exterior and interior of the gun assembly so that the latter is protected from invasion of well bore fluids. The condition of the gun assembly is indicated visually.