The mechanical sampler is an indispensable part of the coal sampling system. As one kind of mechanical sampler, auger sampler is widely used for automatic coal sampling at home and abroad. Top sampler, an experienced Chinese coal sampling system manufacturer, also adopts the auger sampler as the main sampler. However, in this article, we will focus on another type of sampler, the outer spiral binocular claw-type mechanical coal sampler. And we will give some introduction to it.
When the outer spiral binocular claw-type coal sampler is used for sampling, the opening distance of the two claw plates is the real opening size of the sampler. So compared with other samplers, it has the ability to sample the coal with a larger size. During the sampling process, the sampler will firstly rotate vertically downward into the raw material pile with the claw plates in a closed state. After reaching the designated position, the claw plates will open and take an appropriate amount of coal, and then closed automatically. After that, the sampler will be raised counterclockwise to the initial position. The tightness of the closed claws is sufficient to ensure that the collected coal sample will not leak. In addition, the push rod inside the sampler can effectively solve the problem of coal blockage.
The Structure and Feature of the Sampler
The Hollow-type Inner Storage Cylinder
For the outer spiral binocular claw-type coal sampler, the opening distance between the two claw plates is the effective opening size of the sampler and the inner diameter of the hollow-type inner storage cylinder is the effective opening size of the inner storage cylinder. When the maximum outside diameter of the storage inner cylinder is 250 mm, its maximum effective opening size can be up to 180 mm, and the claw-type sampler can sample the coal with the maximum particle size of 60mm. It complies with relevant international standards and national standards that the opening size of sampler shall not be less than 3 times the maximum particle size of the sampled material.
The Piston Self-cleaning Device
The coal samples taken by the claw-type sampler will be raised along the spiral shaft in the direction of the spiral blade rotating. When the moisture content of the coal is more than 10%, they will be easily attached between the surface of the spiral blade and the inner wall of the outer cylinder. More seriously, it will be stuck in the spiral sampler, resulting in the mixed samples or the disruption of coal sampling and preparation. However, the inner storage cylinder of the outer spiral binocular claw-type coal sampler is equipped with a piston push-rod self-cleaning device, which can completely push all samples collected by the sampler out of the inner storage cylinder, thus effectively eliminating the phenomenon of adhesion and blockage caused by the high moisture content of coal samples. In actual operation, the coal samples with total moisture content up to 16% can still be sampled normally.
The hollow-type inner storage cylinder and the piston self-cleaning device make the sampler easier to be maintained. They are in line with international and national standards. Namely, the design and production of mechanical sampler should meet the basic requirements of working under the worst expected conditions and self-cleaning. The above is our brief introduction to the outer spiral binocular claw-type mechanical coal sampler. The auger sampler and it are two samplers that we usually adopt in the coal sampling system. They both have their pros and cons. Hope this article will bring you some useful information.