A connection clamping device (21; 61; 81; 131; 151) arranged for securing a flexible tube (1) to a barbed end (5b) of a tube connector (5), whereby the barbed end (5b) comprises a barb (9) and the tube connector during connection is arranged to protrude into an end of the flexible tube (1), characterized in that said connection clamping device comprises two sections (23 a, 23b) which, during connection when the tube connector protrudes into an end of the flexible tube, are arranged to be connected and locked to each other by a locking mechanism (33a,33b,34a,34b; 63a, 63b, 64a, 64b) around the tube connector (5) and the flexible tube (1), such that the flexible tube (1) is compressed against the tube connector (5) by a rib (41a, 41b) provided on the inner circumference of the connection clamping device.