Leak testing device for pressure vessels

A readily attachable and detachable leak test device for sealing off an inlet neck of an automobile radiator where the neck has a circumferential outer engagement flange and an interior circumferential seat and which can be used for testing a radiator for leaks by injecting air through said device into the interior of the radiator which is then immersed in water to detect any leaks comprising:

• an elongated tubular stem having distal and proximal ends, said stem being threaded on its exterior surface along its length intermediate said distal and proximal ends;
• a circular resilient seal affixed to the distal end of said stem having a diameter greater than the diameter of said stem and corresponding to the diameter of the interior seat for engaging the seat, said seal being backed by a radial flange on said stem to prevent axial displacement of the seal;
• a circular base plate overlapping the open top of the neck having a central aperture for slidingly accepting said stem therethrough, said base plate being placed between said distal and proximal ends of said stem and having at least two pivotable latches affixed on opposite sides of said base plate, each of said latches having a latch hook on one of its ends for engaging the under face of the flange;
• a spring surrounding said stem and positioned between said base plate and said seal;
• and
• a nut bottomed on said base plate, said nut being threaded on said stem;
• whereby the seal is inserted within the inlet opening of the automobile radiator to abut against said seat, said latch hooks engage the outer engagement flange of the inlet opening, said latches are upwardly rotated to provide positive engagement between said rubber seal and said inlet by drawing said base plate toward the neck to compress said spring and load said seal against the seat and air may be injected through the stem from its proximal end into the interior of the radiator to determine the presence of any leaks within the radiator.

A method of testing pressure vessels for leaks where the pressure vessel has a neck with an open top, an out-turned peripheral rim and an interior seat which comprises:

• providing a device for sealing the neck of the pressure vessel, said device having a base member with a central aperture for overlying the open top of the neck, a pair of latches pivotally mounted on said base member having fingers for engaging the underside of the rim of the neck, a hollow stem slideable through the central aperture of the base, said stem having a distal and proximal end, said distal end of said stem having a resilient seal for engagement with said interior seat of said neck, said proximal end having a means for attaching a pressure conduit, said stem having a threaded portion intermediate said distal and proximal ends, a spring surrounding said stem between said base member and said seal and a nut threaded on said stem bottomed on said base member;
• rotating said latches to a first open position;
• placing said resilient seal of said distal end of said stem within said neck of said pressure vessel abutting against said interior seat;
• engaging said fingers of said latches with the underside of the out-turned peripheral rims;
• rotating said latches to a second closed position so that said base member moves toward said neck and exerts a compressive force on said spring which in turn forces said resilient seal against said interior seat;
• affixing a compressed air conduit to said proximal end of stem;
• injecting compressed air into said vessel through said stem;
• and
• submersing said pressure vessel in water whereby a leak in said pressure vessel may be detected by air escaping through said leak and rising through said water as bubbles which may be observed by an operator.