Welding machine for joining together PVC profiles without burrs, the apparatus comprising: - at least one body in which PVC profiles are processed for welding; - at least two sliding tables on the at least one body where the profiles to be welded are placed, - at least one clamping unit having at least one clamping element adapted for fixing the profiles placed on the sliding tables, - at least one processing group adapted for opening a welding groove on the fixed profiles, - at least one heating element adapted for melting the profiles in order to join the profiles brought together by a movement of the movable sliding tables after opening of the welding groove; - at least one thrust plate adapted for adjusting the thickness of burrs, which may occur on flat joint surfaces of the profiles due to the welding groove, but which do not occur on the edges of the profiles, by compressing the flat joint surfaces from side surfaces of the profiles, and - at least two moving jaws adapted for moving the fixed profiles to the melting position with the help of an engine and for combining the movement with the pressing of the profiles against each other, characterized in that - the at least two sliding tables are adapted for being moved by a movement element, thereby allowing a burr width to be adjusted by means of an adjustment mechanism, and in which cleaning and welding positions can be adjusted by controlled horizontal movement, and in that the welding machine comprises: - at least one cleaning unit adapted for cleaning the burrs formed on the profile surfaces, with positioning blades on the clamping unit and stripping blades which compensate inclinations of the profiles by means of a spring mechanism, - at least one rest mechanism positioned on the flat joint surfaces of the profiles during the burrs cleaning process of the cleaning unit, which is positioned on the clamping unit and adapted for compensating deviations in the profile length by means of a spring mechanism it has, - at least one frame repulsion element adapted for removing welded profiles from the body and - at least one positioning bearing adapted for ensuring a smooth deburring process. - at least one body in which PVC profiles are processed for welding; - at least two sliding tables on the at least one body where the profiles to be welded are placed, - at least one clamping unit having at least one clamping element adapted for fixing the profiles placed on the sliding tables, - at least one processing group adapted for opening a welding groove on the fixed profiles, - at least one heating element adapted for melting the profiles in order to join the profiles brought together by a movement of the movable sliding tables after opening of the welding groove; - at least one thrust plate adapted for adjusting the thickness of burrs, which may occur on flat joint surfaces of the profiles due to the welding groove, but which do not occur on the edges of the profiles, by compressing the flat joint surfaces from side surfaces of the profiles, and - at least two moving jaws adapted for moving the fixed profiles to the melting position with the help of an engine and for combining the movement with the pressing of the profiles against each other, characterized in that - the at least two sliding tables are adapted for being moved by a movement element, thereby allowing a burr width to be adjusted by means of an adjustment mechanism, and in which cleaning and welding positions can be adjusted by controlled horizontal movement, and in that the welding machine comprises: - at least one cleaning unit adapted for cleaning the burrs formed on the profile surfaces, with positioning blades on the clamping unit and stripping blades which compensate inclinations of the profiles by means of a spring mechanism, - at least one rest mechanism positioned on the flat joint surfaces of the profiles during the burrs cleaning process of the cleaning unit, which is positioned on the clamping unit and adapted for compensating deviations in the profile length by means of a spring mechanism it has, - at least one frame repulsion element adapted for removing welded profiles from the body and - at least one positioning bearing adapted for ensuring a smooth deburring process.