新型垂直螺旋输送机的开发应用

常用的垂直输送设备有斗式提升机、垂直型埋刮板输送机、垂直螺旋输送机等。这些设备在输送如糖、麦芽粉、食品添加剂等物料时 ,能否保证其洁净、不受污染 ,一直是一个没有解决的问题。笔者在为安徽科苑集团氨基酸晶体包装车间进行技术改造时 ,就遇到因生产需要而要求将氨基酸晶体从地面垂直提升 1 0m后再行包装的问题。如果采用斗式提升机 ,不管是带式还是链式的 ,输送机在运行中总会有因传动带或传动链条磨损而产生的胶粒 (粉 )或金属粉末掉下而污染物料 ;垂直型埋刮板输送机内的物料随刮板链条而运动 ,物料同样会受到污染 ;垂直螺旋输送…     

垂直螺旋输送机在磷酸氢钙粉料的应用

介绍垂直螺旋输送机在磷酸氢钙粉体输送工程设计中的计算及实际应用情况,可为有洁净要求的细颗粒粉体物料的输送提供借鉴。     

垂直螺旋输送机中颗粒速度的分布

采用离散元方法对垂直螺旋输送机中颗粒的流动进行模拟计算,得到颗粒圆周速度、轴向速度、自转角速度在螺旋空间中的分布. 结果表明,颗粒圆周速度最大在叶片工作面径向位置33 mm处,右下区域内圆周速度变化明显,颗粒受周向剪切力较大. 随径向距离增加,底层颗粒与叶片的圆周速度差变大,至近料槽壁处达峰值,导致叶片远端和边缘处磨损较大. 较大颗粒轴向速度区域在颗粒床中层,最大值在近料槽壁处叶片工作面上方22 mm处. 在左下角出现颗粒流滞流区,颗粒轴向速度小于0.1605 m/s,有些甚至小于0.09625 m/s. 螺旋叶片工作面附近颗粒自转角速度较大,最大值在叶片边缘,且高自转角速度的颗粒都集中在颗粒群下层.     

小直径螺旋输送机物料堵塞的改进措施

小直径螺旋输送机在进行负荷运转时,物料被堵塞在第一个吊轴承和连接法兰位置。通过对出现的物料堵塞原因进行分析,提出将原来的法兰式接轴连接改为轴套连接。有效地解决了物料堵塞的问题。     

螺旋输送机的几点改进

GX 型螺旋输送机在水泥厂有着广泛的应用。其产品已系列化而成为标准定型产品。但在使用中也发现结构上存在一些不合理的问题。针对不同情况,我们作了一些不同程度的改进,经过多年的实践,效果良好。     

螺旋输送机的几点改进

螺旋输送机广泛应用于水泥生产中,但在实际使用中,经常出现故障。我们在维修过程中总结了一点经验,现作一介绍。 1 吊轴承处的改进 由于吊轴处有一段距离没有叶片,此处物料是靠挤压向前输送的,所以易积料,影响吊轴瓦的润滑,加快了轴瓦的磨损。为此在设计制造时,尽量缩短吊轴的长度,同时与吊轴相联接的     

螺旋输送机的连接方式

螺旋输送机的连接方式程鸿机，俞美山东建材学院（２５００２２）在水泥生产流程中，螺旋输送机是使用广泛的设备。螺旋输送机之间及其与斗式提升机之间的连接方式通常都采用《工艺设计手册》所示形式。如图１所示螺旋输送机之间的连接，输送机２在输送机１上方，通过下料...     

链式输送机代替螺旋输送机的效果与体会

1996年初,天津市汉沽水泥厂将两台Φ1.83m×6.4m开流水泥磨改为圈流磨,为了充分利用原有设备,粗粉回磨输送设备仍使用GX400螺旋输送机。系统投产后动力消耗大,15m长的螺旋输送机选用11kW电机,电机频繁烧毁,此后将这台螺旋输送机断为两条,配置18.5kW电机;设备故障率高,     

螺旋输送机轴承座的改进

螺旋输送机轴承座的改进刘纯友湖南省华中特种水泥厂（４１９５１２）我厂１９９１年安装了两台螺旋输送机，用于稳定给料计量煤粉、生料。投入运转后先后出现下列问题：①轴承座经常发热，用黄油枪给轴承座加油很难加入，无法降温；②电机负荷大，联轴器常常损坏；③常需...     

Study of Residence Time Distribution in a Pilot-Scale Screw Conveyor Dryer

The screw conveyor dryer (SCD) finds varied applications in the process industries either as a pre-dryer or for post-drying operation. In certain cases, it can be used as the main dryer. The full potential of SCD has not been exploited for the lack of its understanding. The conveying of paste or particles through a screw conveyor may follow a near plug flow behavior; however, it is essential to ascertain a desired level of inter-particle mixing during the course of drying/conveying so as to obtain the desired drying conditions. The effects of feed rate (15–176 kg/h) and screw speed (10.8–28 rpm) on the RTD were studied for the conveying of sand in a pilot-scale SCD using pulse input of a tracer (dye-coated sand). Two new parameters defining the relative stagnancy and screw effectiveness were introduced to study the flow performance of SCD. The flow in the SCD approaches plug flow with an increase in feed rate or by decrease in the screw speed. A low value of the holdback, a parameter of relative stagnancy, indicates the flow in SCD to be near plug flow. Mean residence time was found to be 3 to 4 times longer than the linear residence time due to lower values of screw effectiveness (0.24–0.32).     

新型物料输送器的设计与实验研究

利用压电陶瓷的逆压电效应,提出一种以双晶片压电振子为驱动源的新型物料输送器。设计了物料输送器的结构并分析其工作原理,建立系统的动力学模型,推导出双自由度系统的位移放大倍数表达式,利用有限元软件Ansys分析系统的工作模态,制作了系统结构的样机并进行实验测试,测试结果表明:在系统共振频率为124Hz时,料道振动输出位移最大,位移输出范围为41~45μm,工作频率范围为121~128Hz,处于共振频率时最大输送速度达58mm/s。与同型号的电磁式振动输送器相比,该样机的电流仅为电磁式的21.71%,输送速度是电磁式的1.65倍,振幅为电磁式的36.6%,噪音降低了41d B。     

An Experimental Study of the Thermal Performance of a Screw Conveyor Dryer

In the present study drying of fine crystalline solid was carried out in a non-insulated jacketed screw conveyor dryer SCD of 3 m length and 0.072 m screw diameter. It is nitrogen-swept to carry off the evaporated moisture. Dryer performance was evaluated in terms of the final moisture content, heat-transfer coefficient, thermal efficiency and power consumption. From the experimental results it was observed that drying under low pressure gives 92% moisture removal compared to 30-40% using low flow rates of nitrogen. The initial moisture content was in the range of 5 to 6%. Over the parameter range studied, the overall heat transfer coefficient was found to be in the range of 46-102 W/m²K. The average rise in the temperature of the product was 40 to 50°C. Thermal efficiency (based on sensible and latent heat) of the dryer obtained was found to be in the range of 25-62%, typical values obtained in falling rate drying period. Power consumption per metric ton of dried material was found to be a strong function of screw speed and material feed rate, material properties, and drive efficiency.     

An Experimental Study of the Thermal Performance of a Screw Conveyor Dryer

ABSTRACT

In the present study drying of fine crystalline solid was carried out in a non-insulated jacketed screw conveyor dryer SCD of 3 m length and 0.072 m screw diameter. It is nitrogen-swept to carry off the evaporated moisture. Dryer performance was evaluated in terms of the final moisture content, heat-transfer coefficient, thermal efficiency and power consumption. From the experimental results it was observed that drying under low pressure gives 92% moisture removal compared to 30–40% using low flow rates of nitrogen. The initial moisture content was in the range of 5 to 6%. Over the parameter range studied, the overall heat transfer coefficient was found to be in the range of 46–102 W/m²K. The average rise in the temperature of the product was 40 to 50°C. Thermal efficiency (based on sensible and latent heat) of the dryer obtained was found to be in the range of 25–62%, typical values obtained in falling rate drying period. Power consumption per metric ton of dried material was found to be a strong function of screw speed and material feed rate, material properties, and drive efficiency.     

Hydrodynamic Characteristics of a Pilot-Scale Screw Conveyor Dryer

This article presents results of an experimental study on the flow characteristics of a pilot-size screw conveyor dryer (SCD). In particular, the effects of granular solids flow rate (15.2–206 kg/h) and screw speed (10.8–28 rpm) on the residence time distribution (RTD) were studied using sand as the model material. The RTD was measured using a dynamic step change in the solids flow rate. Parameters such as solids holdup, degree of fullness, mean residence time, and uniformity of the discharge flow were studied. The solids holdup and hence the degree of fullness was found to decrease with increase in the screw speed and decrease with the solids flow rate. The mean residence time was found to decrease with an increase in the screw speed, as expected. The screw speed and the solids flow rate strongly affected the discharge uniformity. An optimum value of the degree of fullness was observed with regard to the solids flow rate. Over the operating range examined, the solids flow pattern was close to plug flow, as indicated by high values of N and Pe number.     

Hydrodynamic Characteristics of a Pilot-Scale Screw Conveyor Dryer

This article presents results of an experimental study on the flow characteristics of a pilot-size screw conveyor dryer (SCD). In particular, the effects of granular solids flow rate (15.2-206 kg/h) and screw speed (10.8-28 rpm) on the residence time distribution (RTD) were studied using sand as the model material. The RTD was measured using a dynamic step change in the solids flow rate. Parameters such as solids holdup, degree of fullness, mean residence time, and uniformity of the discharge flow were studied. The solids holdup and hence the degree of fullness was found to decrease with increase in the screw speed and decrease with the solids flow rate. The mean residence time was found to decrease with an increase in the screw speed, as expected. The screw speed and the solids flow rate strongly affected the discharge uniformity. An optimum value of the degree of fullness was observed with regard to the solids flow rate. Over the operating range examined, the solids flow pattern was close to plug flow, as indicated by high values of N and Pe number.     

大长径比卧螺离心机螺旋输送器的有限元分析

应用SolidWorks对大长径比卧螺离心机的转鼓-螺旋输送器系进行了三维建模,采用与SolidWorks无缝衔接的有限元分析插件Simulation对其进行了有限元仿真。通过SolidWorks Simulation对螺旋输送器在正常工况下的整体结构进行了静力分析和模态分析,得到了螺旋输送器前5阶固有频率、应力分布和...