Machine tools

• Cold moulding technology – compaction of material
• The skeleton of a special machine is derived from the standard MT 70/3000 CNC lathe machine.
• The function is based on cold moulding technology – rolling of cylindrical, conical and transition radius areas of the shaft parts, i.e. vehicle axles.
• The use of the machine for specialized production of parts using surface rolling technology.
• The form rolling equipment is located on the longitudinal saddle.
• The saddle moves by means of CNC controlled axis Z on the bed of the machine in a longitudinal direction.
• The motion in axis X is performed by tailstock sleeves of rolling heads into which the rolling tools are clamped.
• The tailstock sleeve movement and the rolling force are performed hydraulically.
• The machine is equipped with hydraulic aggregate in the standard variant.
• Fluent changes in the pressure and the force on the rolling tools during the work cycle in a defi ned pressure scope.
• Indirect independent measurement of the rolling force; recording and archiving.
• Tailstock with hydraulically tailstock sleeve is equipped with special mechanical arrestment equipment for the safe transfer of axial forces.
• The headstock is placed on the bed on the reinforced centre.
• Independent oil management, including the tank and the tube under the work area of the machine.
• The whole rolling saddle system is integrated into the covered area of the machine.
• Sliding guiding areas for additional rolling saddle are connected to the central lubrication system of the machine.
• The machine can be operated in manual and automatic cycles.

The advantages of a rolled surface are that it achieves a smooth surface of the part by cold forming the surface layer. The quality of machining replaces the grinding technology, but without the accuracy of the dimensions of the machined surface as in grinding. Rolling is suitable as a finishing operation for strengthening surfaces of non-tolerated dimensions or as a technology for strengthening the surface layer before finishing grinding the surfaces to the tolerated dimension.

Rolling is used mainly for reasons of material savings of up to 8%, higher resistance to fatigue fracture, ie higher fatigue strength in cyclic stress of the part, increased hardness and very smooth surface, provides higher resistance to abrasion and corrosion, another significant advantage for environment is the possibility to replace molybdenum spraying by surface rolling.

1. The working space of the machine where in the fi rst row there are distances and dimensions concerning the clamping of the shaft, the so called spindle clamper, the distance of the clamper face from the face area of the spindle 275mm, starting the tailstock of the machine (related to the distances of the inserted tailstock sleeve from the face of the spindle, i.e. 3412mm, size of the expansion of the tailstock 160mm and the distance of the movablecentre tool (in this case Röhm MK6 VEL.116 – Id.Nr.093439 centre) from the face of the tailstock sleeve 192mm. The total distance between pins is then 2876-2906mm depending on the form and the size of the centric axle pit. In addition, in the work space there is an indication of the starting support with rolling rolls with the distance only to the face of the spindle and the face of the inserted tailstock sleeve; there is also angular deviation of the rolling tailstock sleeves (±35 degrees), the position of the centre where the tilting is performed, i.e. 290mm and the value of the distance of the faces of the inserted tailstock sleeves for the rolling heads 522mm and the expansion of each tailstock sleeves 112mm. Most dimensions are stated to the face of the spindle, the face of the tailstock sleeve and the faces of the tailstock sleeves of the rolling heads, because the independent clamping device into the spindle, the centre into the tailstock and the rolling tools are selected and constructed especially according to the requirements of the client and their values may differ.
2. Maximum clearance of the part without tilting the rolling heads.