1. Field of the Invention
This invention relates to pressure containment apparatus, and, more particularly, to cylindrical apparatus for containing a leaking cylinder out of which gas is leaking.
2. Description of the Prior Art
There are no known U.S. patents which disclose container apparatus designed to hold a leaking gas tank or cylinder until the tank or cylinder can be disposed of. However, there are several U.S. patents which disclose apparatus for sealing a leaking valve on a tank. In each patent, there are special elements associated with the valve or the tank that make the sealing of the valve itself possible. None of the elements associated with the sealing of the valve comprises a pressure vessel itself.
In U.S. Pat. No. 2,465,095 is disclosed a frame in which a tank having a leaking valve is placed. The frame includes elements for sealing the top portion of the tank.
U.S. Pat. No. 3,323,541 discloses apparatus with another type of sealing element for the top of a tank having a leaky valve. The sealing element cooperates with external threads at the base of the leaking valve.
U.S. Pat. No. 3,756,450 discloses apparatus for retaining a protective cap over a leaking valve of a tank. The apparatus does not appear to be designed to prevent leaking, but rather is designed to provide a protective housing for the valve.
The following four U.S. patents disclose apparatus designed to contain parts of a tank or pressure vessel that may explode. The various apparatus described in the patents contain fragments from the exploding tank, but do not contain the contents of the tank. They are primarily designed for nuclear pressurized reactor vessels. The patents include U.S. Pat. Nos. 3,910,447, 3,937,351, 3,963,565, and 3,970,208.
There are other U.S. patents which disclose apparatus for securing a top or dome to the bottom of a cylinder or other vessel designed to hold pressure. Examples of such patents include U.S. Pat. Nos. 1,384,915, 1,597,270, 1,894,652, and 1,900,627.
The U.S. Pat. No. 1,384,915 discloses a tank closure having a number of fixed studs that are engaged by hooked elements on a cap. The U.S. Pat. No. 1,597,270 discloses another type of hooked members which engage pivoting studs. The pivoting studs are secured to the tank. In the U.S. Pat. No. 1,894,652, pivoting studs are again used and are engaged by hooked elements. In the U.S. Pat. No. 1,900,627, in addition to fixed elements being secured to fixed studs, there is a safety retainer system that prevents rotation of the caps except when the nuts are completely loose. The tank top is prevented from turning when the top or dome is completely tightened against the tank. Thus, vibration could not cause the tank top to be rotated against the pressure of the nuts if the nuts were to inadvertently loosen to a slight degree.