Connecting devices for sealing connection between two pipe ends have previously been used which have an internal diameter fitting the outer diameter of one of the pipe ends and an external diameter fitting the inner diameter of the other pipe end. These seals must therefore be manufactured with tolerances in relation to the diameters of the pipes to be joined, which means that very many seals must be available in order to provide connections between pipe ends of varying diameters.
It is also known through U.S. Pat. No. 3,913,928, for instance, to use one and the same connecting device to join a pipe of a specific diameter to another pipe of a specific diameter, where this second pipe can assume one of two possible diameters. In this case the connecting device is provided with a collar that can be peeled back over the device so that it assumes a larger outer diameter. This type of connecting device must also be manufactured with tolerances in relation to the pipes and many devices are required to cover many ratios between diameters.
Also known through SE patent 9600828-9 (510 262) is a flexible nipple, a so-called combination nipple, by means of which a first pipe is connected to a second pipe, the first pipe assuming one of two possible diameters and the other pipe also assuming one of two possible diameters. However, this type of connecting device must also be manufactured with tolerances to enable connection to specific pipe diameters. One variant of said combination nipple is manufactured, for instance, under the designation 75-70/50-40 and another under the designation 64-58/50-40 signifying D1-D2/d1-d2 which means D1 or D2 connected to d1 or d2.
Difficulties are thus encountered with these known connecting devices in joining a first pipe to a second pipe, using the same connecting device, where the diameter of one of the pipes is permitted to lie within an interval rather than having a specific value. It also is difficult to obtain a tight connection to a pipe end that is not entirely circular.