Coal is a kind of material in bulk. The quality is the only condition to make a price for the coal, so how to judge the quality of the coal is the most important. How to judge the coal quality? Sampling, sample preparation, and the sample analytics are the main methods to judge the coal quality. Among that, sampling is the first stage and it is the crucial part.
The research said the bias caused by the sampling accounts for 80%. In the past, the main sampling method was manual sampling. Nowadays, the manual sampling gradually eliminated, mechanical sampling became the mainstream. Why more and more factories adopt the mechanical sampling system?
Compared to the manual sampling method, the automatic sampling machines have its obvious advantages:
- The mechanical sampling system improves the work efficiency;
- To the greatest extent possible to avoid the artificial factor of fraud.
- The sample is representativeness.
- The mechanical sampling system can provide a randomized and accurate coal sampling procedure.
For the structure, the mechanical sampling system has two main parts that are sampling system and sample preparation system. And the sampling machines can be divided into two types that are cross belt sampling system and auger sampling system. The common mechanical sampling systems are the auger sampling system and the cross belt sampling system, either. What is the difference between two types sampling machines? How to choose the suitable coal sampling system according to your requirements? TOP-SAMPLER will help you have a rough idea of the mechanical sampling system.
Cross-belt sampling system
Cross belt sampling system is used to collect coal sample from the conveyor belt. When collecting the coal samples, the cross belt sampling system should intercept a complete cross-section of coal as sub-sample and the sample should not be filled with the sampler collector and overflow from the sample collector. We have introduced how to select cross belt sampling system before.
Cross belt sampling system has two main samplers that are head belt sampler and central belt sampler.
The head belt sampler installed in the conveyor belt head position. Rotary head belt sampler rotates a revolution at regular intervals to collect the primary sample increments from the falling coal stream according to the program (PLC system sets). These primary increments will enter the primary belt feeder through the coal chute. Then the primary increments will enter the sample crusher, sample divider, and the sample container. And the residue return system will return the reject to the main conveyor belt.
The central belt sampler installed in the middle of the conveyor belt. The central belt sampler will collect the primary increments from the moving stream directly. The working principle of the central belt sampler is the same as head belt sampler. If you have any questions you can contact TOP-SAMPLER to learn more.
Auger sampling system
Auger sampling system is mainly used to collect coal sample from the railcar, truck with coal, coke or other bulk materials. These samples are used to establish the commercial value of the coal so the sample has representativeness or not is crucial.
This auger sampling system has two main types that are door type and crane type.
How does the auger sampling system to collect coal samples? An auger sampler will extract a vertical column of coal from the railcar or truck as it passes under the auger. When the auger sampler out, it will be filled with coal that means complete a primary coal sample increments taken. The primary increments will send to the primary feeder, sample crusher, sampler divider and enter the sample collection container finally. The rest coal or others material will return to the vehicles through the residue return system.
As coal sampling methods, the auger sampling system and the cross belt sampling system has its unique characters. The obvious difference is the cross belt sampling system is suited for the coal moving belt, and the auger sampling system is suited for the railcar, truck with coal and the coal storage. What’s more, both of them are used to other materials like coke, iron ore and wood pellets than just coal.
Besides the coal sampling system machines mentioned, the sample preparation system is a part of the sampling system. The sample divider and sample crusher are also important for making the sample.
As a Chinese coal sampling system machines manufacturer, TOP SAMPLER will be your trustworthy business partner. We are good at manufacturing the coal sampling equipment includes auger sampling system, cross belt sampler, sample preparation system machines and sample analytics system machines. We advocated supplying the best sampling equipment for you. What’s more, we are good at customizing the feasible projects for each client according to your requirements. Welcome to contact us!
