钢材认为，目前市场主要以等待需求释放为主，钢厂也好，商家也罢，均在围绕着需求做文章，但是下游需求量何时开始释放，惯例在2~3月很难集中，商家谨慎控制好库存及其结构，多关注下游需求及资金面的变化。份国内钢铁市场仍处于需求淡季，成本支撑力度有所加强。春节后厂商拉涨意愿强烈，但因寒冷天气影响室外施工，季节性需求难以在短时间内启动，预计2月份国内钢铁市场仍将弱势运行，呈现前高后低的走势，前期拉涨走高，后期因需求与价格难以承接而回落。
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三螺杆泵的流量与转速成线性关系,相对于低转速的螺杆泵,高转速的螺杆泵虽然能增加了流量和扬程,但功率明显增大,高转速加速了转子与定子间的磨耗,必定使螺杆泵过早失效,而且高转速螺杆泵的定转子长度很短,极易磨损,因而缩短了螺杆泵的使用寿命。通过减速机或无级调速机构来降低转速,使勘转速保持在每分三百转以下较为合理的范围内,与高速运转的螺杆泵相比,使用寿命能延长几倍。现在市场上的螺杆泵的种类较多,相对而言,进口的螺杆泵设计合理,材质精良,但价格较高,服务方面有的不到位,配件价格高,订货周期长,可能影响生产的正常运行。
