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The problem of unqualified quality of grid steel

更新時(shí)間:2021-02-04 09:56:52?點(diǎn)擊:46825 ? Grid Knowledge

In the process of steel structure grid construction, the choice of steel is very important, because the quality of the steel directly affects the quality of the grid building, so it is necessary to do a good job of testing the steel quality. The following is Jiangsu Huahai Steel Structure Compile an introduction to the causes and prevention measures of steel unqualified.


Reasons for quality problems of grid steel

1) Failure to follow normal standards during the purchase process. If the quality of the dealer’s products is not reviewed, large quantities of steel products and steel castings will be purchased.

2) The mechanical properties and chemical composition of the selected steel do not meet the requirements of the country, or a forged certificate is a low-quality product.

3) The purchased steel does not have a quality specification, which means that there is the ability of inferior steel.

4) Quality problems occur during the transportation of steel.

Preventive measures for quality problems of steel structure grid

1) In the process of purchasing steel products, a large number of purchases can be made only after the dealer's products are qualified. After a series of formal approval procedures, the purchase requirements are met to prevent the purchase of unqualified steel products.

2) There is a match between the selected steel and the welding process. Pay attention to the problem of laminar tearing of the steel when purchasing.

3) The steel should be protected during product transportation to avoid welding consumables.

4) Stacking should be carried out in batches to prevent serious corrosion of steel, which directly affects the quality of steel, and sampling must be carried out according to relevant standards.

5) Strictly purchase steel materials in accordance with the acceptance criteria. The steel materials purchased must have certification materials and meet the design standards and comply with national standards.

6) Pay attention to setting the chemical composition and mechanical composition during the purchase of grid steel, and test the processing technology if necessary to see if the product meets the qualified standard.

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