Machine construction and performance
1. Construction of the drawing machine
(1) Machine body:
A.Material:HT200
B.Processing:The machine body is formed by monoblock casting, heat treatment to relieve internal stress and boring by a precision boring lathe and features non-deformability, high accuracy and stability.
(2) Driving shaft:
AMaterial:40Cr with thermal refining and high frequency surface treatment
B. Processing:The shaft core undergoes HB250~280 thermal refining in order to relieve internal stress and provide good overall mechanical properties. The matching surface is finely ground with the high frequency technique to ensure quality of fit,core concentricity and perpendicularity.
2. Power transmission
(1)High efficient flat belts made by HABSIT, Switzerland, are used to drive the individual drawing capstans, while the take-up shaft is driven by a separate motor and inverter. The take-up speed is continuously regulated by the inverter based on the feedback messages from the tension bar.
3. Traverse
(1)Traverse mechanism:Traverse is driven by a 90W low speed magnetic synchronous motor. Movement of the traverse bar is controlled by flat belt drive. Three parallelly mounted columns with ball bearing in linear movement ensure sensitive reaction, steady traverse and good traverse quality.
(2)Adjustment of traverse width:The position of the limit switches is adjusted by regulating the screw to suit the reel width. The left screw is used to adjust the outer width of the reel, while the right screw is used to adjust the inner width of the reel.
4. Reel loading/unloading
(1)An easy-to-operate three-jaw expansion sleeve clamp is used to clamp the take-up reel. A reel loading/unloading carriage and slope board are provided beneath the take-up shaft to reduce labour. Fully closed protective cover is provided with a sight glass to observe the take-up and traverse operations. A special-purpose wrench is provided for reel loading/unloading.
5. Protective brake
(1) Imported advancedmagnetic brake with high quality is used, which features automatic braking upon wire breakage or inverter tripping.
(2)When the set length is reached, the machine will slow down within 30~50s and is automatically braked at near stop so as to prevents wire breakage and wire confusion.
6. Inching
(1)A foot switch is provided which may be used to make the machine run at low speed(ca.100~120 m/min)during the threading process.