| 主权项 |
1. A check valve housing for a check valve, comprising:
a check valve housing body comprising a check valve flange at a flange interface; a tab that extends beyond an outer diameter of the check valve flange to ensure that the check valve is installed in a proper position and direction relative to upstream and downstream ductwork; a first and second hinge support extending from the check valve housing body; and a stop coupled to the first and second hinge supports, the first hinge support comprising a first hinge pin interface having a first hinge pin hole to receive a hinge pin, wherein a ratio of a diameter of the first hinge pin hole to a thickness of the first hinge pin interface is between 2.44 and 2.66 and the second hinge support comprises a second hinge pin interface having a second hinge pin hole to receive the hinge pin, wherein a ratio of a diameter of the second hinge pin hole to a thickness of the second hinge pin interface is between 2.18 and 2.37. |
