Different Types of Screw Sand Washer

The high weir screw washer, low weir screw washer, and submerged screw washer are three different types screw sand washing machine. The biggest difference is the design of the bottom water tank. The screw sand washer is commonly used in conjunction with the crusher and vibrating screen in the sand washing line. And also used for grading ore and fine mud in gravity concentrators, and grading the size of ore slurry in the metal ore dressing process, or desliming and dewatering in ore washing operations.

The spiral sand washing machine is equipped with a longitudinal long shaft in an inclined semicircular groove, and a rotating blade is installed on the shaft, which is driven by the upper transmission mechanism to rotate, and the lower part has a spiral lifting device. The spiral sand washing machine relies on the principle that the solid particles are different in size and specific gravity, so the sedimentation speed in the liquid is different. The fine ore particles float in the water and overflow, while the coarse ore particles sink to the bottom of the tank and are pushed upward by a screw to be discharged to the upper part of a device for mechanical classification. It can filter the material powder ground in the mill, and then screw the coarse material into the feed port of the mill using a spiral blade, and discharge the filtered fine material from the overflow pipe.

The main component of the screw sand washer is the spiral. According to its position in the tank and the height of the slurry surface, it can be divided into three types: low weir type, high weir type, and submerged type. The functions and applications of these three types nearly the same, both for washing and particle classification.

1. Low weir screw washer

The low weir type is that the overflow weir is lower than the spiral shaft of the spiral. Due to the small area of the settlement area, it can only be used to wash the placer with little mud and the dehydration of coarse particles in actual production, but it is rarely used in the grinding cycle.

2. High weir screw washer

The high weir type means that the overflow weir is higher than the spiral axis of the spiral but lower than the upper edge of the spiral at the overflow end. There are high weir single helix and the double helix. The settlement area of the high weir screw sand washing machine is relatively large. The height of the weir can be adjusted within a certain range to adjust the granularity of the classification. High weir spiral sand washer is a kind of equipment commonly used in the sand washing process and grinding cycle.

3. Submerged screw washer

The submerged screw sand washer has 4-5 spiral blades at the end of the overflow weir, all of which are sunk in the slurry. There are high weir single helix and the double helix. The submerged screw sand washer has a large settlement area, a deep grading pool, and the spiral agitation has little effect on the surface of the slurry, so the grading surface is stable, and the overflow is large and fine.