Difference between the Heat No.and Lot No.

Heat and lot number equivalent to steel ID card. Heat number refers to the number of furnace steel making furnace, each out of a furnace to do component analysis, heat number is qualitative steel born. Lot number is the heat treatment of steel labels. Each batch of products to do mechanical analysis, process performance inspection. Heat and lot number is proof of steel traceability.

Heat number is the number of refining a number of steel furnace, according to the number of the furnace can check the quality of the furnace steel and the quality of the situation, because the refining of each furnace steel laboratory data records. Each out of a furnace to do component testing and mechanical testing, different furnace out of the steel composition and performance are different.

Lot refers to the same batch in the same batch of steel production, each batch of products have to do mechanical analysis, inspection of process performance, lot number is proof of steel development. According to this lot can be found in this lot of steel raw data, but also according to the lot number found heat number. A heat number can be divided into several batches, the same number with the same heat plate size can be different, the material is not the same but must be the same level of steel; a furnace can have more than one batch, with the heat treatment process.

Sometimes, you will see the lot number: If Gr.b this material manufacturers a lot, certainly produced a lot of furnace, and then shipped to be issued in lot, there is one for each batch number. Therefore, the same lot number, different heat number is likely, but if there is a quality problem, you can check out the furnace in question. The same lot number, each furnace in the processing, within the allowable range will be a little bit different. A furnace can have more than one batch, with the heat treatment process normalizing treatment, together with a group of heat treatment.

In steel production, the steelmaking furnace has a unique furnace number for each smelting, and the steel produced by each ingredient has a unique batch number. After the steel is formed, it is rolled into a cylinder, and each cylinder has a coil number.

In operation, one batch of ingredients (one batch) can smelt multiple furnaces of molten steel (multiple furnace numbers are produced), and each furnace of molten steel can produce multiple coils of steel (multiple coil numbers are produced). Generally speaking, a serial number on a steel coil includes the batch number-heat number-coil number.

The furnace number is the same as the batch number, which is normal. The furnace number is the batch number of this charge, and the batch number is the batch number of rolling production.
General steel pipes (for example: seamless pipes) will be marked: furnace number + batch number, and some manufacturers will mark: furnace number + batch number + material serial number (which steel pipe of the batch)

What is the purpose of numbering?

The purpose of numbering is, firstly, to facilitate the arrangement of production; secondly, to facilitate quality control, and take back products with the same furnace number or batch number when quality problems are found; thirdly, when an accident occurs in the hands of the end user, the production information at that time can be traced according to these marks , to facilitate the identification of whether there is a quality problem in the material.

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