Hinge assembly to pivotably mount blind flange to pipe weld neck flange

A hinge assembly for use with both blind flanges and weld neck flanges having tolerances on thickness, the hinge assembly pivotably connecting a blind flange to a weld neck flange coupled to an opening of a pipe, the hinge assembly comprising:

• a front assembly comprising a front plate, a first support plate directly coupled to a side edge of the front plate, and a plurality of front link plates directly coupled to the first support plate, the front plate extending in a first plane and the first support plate extending within a second plane, the first plane being oriented generally perpendicular to the second plane, the front plate comprising a plurality of openings, each opening in the plurality of openings in the front plate coupled to a first set of mechanical fasteners to secure the front plate to the blind flange;
• a rear assembly pivotably mounted to the front assembly, the rear assembly comprising a rear plate, a second support plate directly coupled to a side edge of the rear plate, and a plurality of rear link plates directly coupled to the second support plate, the rear plate extending in a third plane and the second support plate extending within a fourth plane, the third plane oriented generally perpendicular to the fourth plane, the rear plate comprising a plurality of openings, each opening in the plurality of openings in the rear plate coupled to a second set of mechanical fasteners to secure the rear plate to the weld neck flange, each front link plate in the plurality of front link plates being disposed between a pair of adjacent rear link plates in the plurality of rear link plates;
• a first handle coupled to the front plate;
• a second handle coupled to the rear plate;
• and
• a pin disposed through each front link plate and the pair of adjacent rear link plates, the pin configured to permit pivotal movement of the front assembly relative to the rear assembly to enable the blind flange to open and close relative to the weld neck flange;
• wherein the front assembly is configured to pivotably adjust relative to the rear assembly to a closed position with the first and third planes parallel to each other and the second and fourth planes coplanar relative to each other, wherein the front assembly is configured to pivotably adjust relative to the rear assembly to an open position with the first and third planes coplanar relative to each other and the second and fourth planes parallel to each other.