A study on the behaviors of the D-ring with a curvature radius using the photoelastic experimental hybrid method

Sealing is always a very important mechanical element when damage, breakage, leakage or even more serious disasters occur. Sealing has a range of cross-sections, such as O-rings, X-rings, Square-rings and D-rings, which is used in many ways. The cross section of a Dring without curvature radius is simply combined with the half cross sections of an O-ring and Square-ring. The general D-ring has the same corner angle as the Square-ring's corner. Therefore, a stress concentration can easily cause damage. To reduce this stress concentration, a D-ring without curvature radius should be changed into a D-ring with a curvature radius on the square corner. Stress analysis of a D-ring with a curvature radius is needed. In this sturdy, the stress of a D-ring with a curvature radius under a uniform squeeze rate 20% and various internal pressures was analyzed by using a photoelastic experiment hybrid method. The results showed that the D-ring with a curvature radius has the advantages of both an O-ring and Square-ring, and the magnitudes of the contact stress in the D-ring with a curvature radius are almost constant along the contact line. This means that the packing ability of a D-ring with a curvature radius is excellent.