The present invention relates to a hose connection piece having a region for the reception of a hose end and to a hose coupling and to a hose fitting having such a hose connection piece.
Such hose connection pieces, hose couplings and hose fittings are used widely in the most varied sectors. One area of application is the use of hose fittings as hydraulic fittings such as are used with construction machinery.
Hose connection pieces are usually designed as hose nipples or as hose nozzles with a section for the fixing of the hose end. To withstand peak loads and high pulsed loads, the hose end is as a rule pressed onto the hose connection piece.
A disadvantage with the hose connection pieces used today consists of the fact that leaks and the known “sweating”, i.e. the occurrence of liquid at the hose connection piece and the subsequent failure of the hydraulic lines can occur after longer use.
One reason for this is that the hydraulic medium, for example hydraulic oil, migrates between the hose connection piece, that is the hose nipple, for example, and the inner hose core under the pulse pressure and is then discharged at the hose end. As the time of use of the hose increases, the probability grows that the hose fails for this reason. The reasons for the said leak can be fatigue phenomena of the inner hose core and also the formation of cracks in the inner core of the hose in the region of the link.