SURFACE QUALITY OF HIGH PRECISION COLD DRAWN SEAMLESS STEEL TUBE
High precision cold drawn tube surface roughness Ra ≤ 0.8μm, diameter size accuracy can reach H9 ~ H10, only to ensure that after honing to H7 ~ H8 bore size and Ra ≤ 0.2μm of the internal surface roughness requirements. In addition to the honing machine equipment precision, the cold drawn tube surface quality is another key point, cold drawn tube internal surface defects by the domestic A factory measured data classification, there are three kinds of main honing pipe surface roughness. 1. Pitting: After rough drawing, the surface can be found by many pits-like defects, such defects will not seriously affect the smoothness of the cylinder bore, for the cylinder is a waste. 2. Scratch: Scratch defects are cold drawn, generally along the axis of a steel pipe along the direction of the scratches, there must be more than the depth of the scratches honing margin, it is possible to grind away such defects, processing a qualified cylinder . 3. Not round: Cold dra...