Patent attributes
The invention relates to the external sealing and joining of piping. More particularly, the invention provides an improved seal profile which is suitable for use inside pipe couplings. The invention provides a twin-lip seal profile particularly useful in combination with a pipe coupling, the seal comprising: a substantially flat base element, having a first (inner) face and a second (outer) face and two outer edges. Two spaced-apart support blocks projecting upwardly from the first face of the base element, each support block having an outer and an inner face. Two lip members projecting from the outer edges of the base element, the lip members overlapping and resting on the closest support block and leaving a hollow space between the base element, the lip member and the outer face of the support block. The seal profile being characterized in that the plane or line of contact between the lip member and the support block, when extended towards the center of the profile, slopes to more closely approach the substantially flat base element, thus forming a wedge-like effect when pressure is applied to the lip members, the wedge-like effect preventing undesired outward movement of the lip members.