is formed so that support racks or corresponding support shelves 61a are fixed to the side wall of the applicator beam 40 by means of fastening members 62a the fastening members 62a may consist of screw members or equivalent but the fastening of the support racks or equivalent support shelves 61a to the wall of the applicator beam 40 can also be carried out for example by welding thus while a portion of each support shelf is fastened to the side wall of the applicator beam 40 another portion of each support shelf 61a forms a horizontal support for the unit 50 that includes the coating head which unit 50 rests on support of the support shelves 61a the unit 50 is attached to the support shelves 61a by means of a joint 60a which is for example a dovetail joint shown in fig3 a or an equivalent backed off joint which permits movements of the pieces to be joined together in one direction i e in this case in the cross direction in relation to the machine direction but prevents relative movements in all other directions in the illustration in fig3 a the joint 60a has been formed so that the joint 60a is attached to the support shelves 61a and a groove having a corresponding shape to the joint 60a is formed into a lower portion of the frame 51 of the unit 50 that includes the coating head in this respect the arrangement can of course also be inverse from that shown fig3 a also shows the unit 50 that includes the coating head being installed on the support shelves 61a so.