Cutting insert and a cutting tool for milling square shoulders

A milling cutting tool comprising:

• at least one cutting insert including a top surface, a bottom surface and a peripheral side surface extending between the top and bottom surfaces, the peripheral side surface including two pairs of opposing side surfaces, at least a first of said pairs of opposing side surfaces being provided with two opposing major cutting edges at an intersection of a respective side surface with the top surface and a second of said pairs of opposing side surfaces being provided with two opposing wiper edges at the intersection of the respective side surface with the top surface, each respective wiper edge being connected to its associated major cutting edge at one end of the respective side surface, each of said opposing side surfaces of said at least first pair of opposing side surfaces including two generally flat and non-coplanar support surfaces arranged consecutively with respect to a direction of an extension of a respective major cutting edge and making different angles with a normal to said bottom surface, wherein an upper border forming a limit of said support surfaces of each said side surface most distant to said bottom surface is inclined with respect to said bottom surface so that the distance of said upper border to said bottom surface increases in a direction of extension of said major cutting edge towards said wiper edge connected to this associated major cutting edge;
• a tool body including a front end and a rear end, between which a central rotation axis extends around which the tool is rotatable in a direction of rotation, and at least one insert pocket formed in a transition between the front end and an envelope surface extending between the front end and the rear end of the tool body, said insert pocket including adjacent side and rear walls generally transvers to a base, the side wall being provided with two generally flat and non-coplanar radial contact surfaces arranged consecutively along the direction of said rotation axis in the form of a forward radial contact surface and a rear radial contact surface making different angles with a normal to said base and configured to form support for the support surface most distant to said wiper edge and the support surface closest to said wiper edge, respectively;
• and
• a fastening device configured to secure said insert in said pocket while pressing said two insert support surfaces against said rear and forward radial contact surfaces of the pocket.