Thanks to the high machining precision when grinding the upper and lower surfaces, a thickness accuracy tolerance of 25 micrometers can be attained, as the Dutch exhibitors point out. The stationary head configuration is said to guarantee high sheet thickness accuracy, since this accuracy only depends on the position of the grinding belt with respect to the slide moving underneath. To ensure extra precision, the temperature of the cooling fluid, namely water, is thermostatically maintained at 20°C with a tolerance of some tenths of a degree. The fluid can recirculate with the use of a filter that removes grinding waste. The workpieces are clamped on the movable slide with atmospheric pressure, thanks to the vacuum suction below. As is also emphasized, the complete main grinding head can be accurately adjusted in a vertical direction to meet the nominal sheet thickness and to compensate for grinding belt wear. It is reportedly possible to calibrate sheets with a thickness as low as 0.18 mm. The base frame, which is almost 15 m long, consists of a stiff welded construction, supporting stone-ground prismatic guideways on which recirculating ball units run. The table itself is driven by a rack-and-pinion unit with a pre-tensioned gearwheel.
Precision grinding for the fine machining of sheet metal
Timesavers International will be introducing the latest generation of precision grinding machines from their 81 series. The grinders are deemed particularly suitable for the fine machining of titanium, corrosion-resistant steel, aluminum and other metallic materials with maximum lengths of 7,500 mm and widths up to 2,100 mm.