Clamping and fixing device for machining civil air defense door sealing beam

The utility model relates to a clamping and fixing device for machining a civil defense door sealing beam. The clamping and fixing device comprises a support, an L-shaped supporting plate arranged on the support and a clamping part arranged on a sawing machine. Scale marks are arranged on the supporting plate; a positioning part is arranged on the supporting plate; the clamping part comprises a clamping bolt and a base; a first clamping part and a second clamping part are respectively arranged on the base; a sliding groove is formed in the center of the base in the length direction. A bump is arranged at the bottom of the second clamping part and is positioned in the sliding groove, so that the second clamping part can slide on the base; positive and negative threads are arranged on a screw rod of the clamping bolt; the clamping bolt can penetrate through the second clamping part and is in positive and negative threaded connection with the second clamping part and the base respectively; the positioning part c