The invention relates to a drum-type valve (1; 101; 201; 301; 301′) comprising: a partial cylindrical surface forming a first area (2; 102; 302); two circular segment surfaces each forming a second area (3; 103; 303), and; an outer encircling edge (4; 104; 304), which is disposed essentially in two planes, outwardly projects, and which is rests against correspondingly formed contact surfaces, whereby the drum-type valve (1; 101; 201; 301; 301′) has at least one second edge (5; 105; 305).