1860MPa级1×7-15.20预应力钢绞线半成品钢丝质量控制

Quality Control of Semi-finished Steel Wire for 1860MPa Grade 1×7-15.20 Prestressed Steel Strand

预应力钢绞线半成品钢丝的质量控制主要从以下几点着手:盘条抗拉强度优选为1150~1220MPa,严格控制网状渗碳体组织出现;盘条酸洗液的盐酸浓度ω(HCl)为4%~18%;磷化液总酸度80~120点,游离酸度8~10点,磷化温度65℃~75℃,磷化时间2~4分钟;拉丝工艺采用9道次拉拔,各道次压缩率小于23%,拉丝模具工作锥角度为9°~16°,定径带为0.1~0.4d,拉丝模具盒的水温不大于30℃,拉丝卷筒温度40℃以下。

The quality control of semi-finished steel wire of prestressed steel strand mainly starts from the following points： the excellent tensile strength of wire rod is 1150 -1220MPa,the appearance of netlike cementite is strictly controlled, the hydrochloric acid concentration ω （HCl） for wire rod pickling is 4% -18%,the total acidity of the phosphating solution is 80-120 points, the fee acidity is 8 -10 points,the phosphating temperature is 65℃ -75℃,the phosphating time is 2 -4 min ,the drawing process is 9 times drawing, the compression ratio of each pass is less than 23%, the working cone angle of the drawing die is 9°-16°,the length of sizing bench equals to the 10%？40% of the bore diameter of die, the water temperature of the drawing die box is not more than 30 t, and the drawing drum temperature is below 40℃.