This coupling (R) comprises a male element (A) with a stepped outer groove (20), a female element (B) with locking balls (7), a locking ring (9) provided with a front inner notch and a rear inner notch axially separated by an inner rim, a spring that pushes the locking ring (9) back into the forward position, and a valve movable in the female element (B) and pushed by a spring (14) back to the closed position. The male element (A) comprises a valve movable in an inner channel (200) of the male element (A) and a spring (48) that pushes the valve of the male element (A) back toward a closed position of the inner channel (200).

An apparatus and method for crimping coupling rings are provided. The apparatus generally has a lower clamp head and an upper clamp head that may be drawn together by a fastener. The lower and upper clamp heads are designed to receive a first portion and a second portion of a coupling ring, respectively. A first and second post holds the clamp heads adjacent to each other. The upper clamp head is secured to the first post such that the upper clamp head may rotate in a generally circular motion to switch the apparatus from a closed to an open configuration, or vice versa. When the apparatus is placed in a closed configuration, the fastener may be engaged to draw the clamp heads together to increase the compressive force imposed on a coupling ring until the coupling ring becomes crimped.