During the manufacturing process, can the steel plate still be used after its surface is damaged?

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During the manufacturing of pressure vessels, mechanical damage is inevitable on the surface of the steel plates. But to what extent of damage can the material still be used? How should the repair be carried out? The specifications state as follows: GB/T 150-2011 \"Pressure Vessels\" 1. Mechanical damage to the material surface should be avoided during manufacturing. Sharp scars, as well as local defects such as scratches and grooves on the corrosion-resistant surface of stainless steel containers, should be polished, with a maximum polishing slope of 1:3. The grinding depth shall not exceed 5% of the steel thickness δs at that location, nor more than 2 mm; otherwise, repair welding shall be performed. 2. For the formed parts, surfacing parts, and metal lining layers of composite steel plates, the grinding depth shall not exceed 30% of the thickness of the coating (or surfacing layer, lining), nor more than 1 mm; otherwise, rewelding shall be carried out. HG/T 20584-2020 \"Technical Specifications for the Manufacture of Steel Chemical Containers\" stipulates that both the steel plates used for pressure-bearing components and the surface quality of the steel plates after the containers are manufactured must meet the following requirements: 1. The surface of the steel plates may have local defects such as scratches, rolling marks, pitting, and roughness resulting from the removal of oxide scale, provided that the depth of these defects does not exceed half of the negative deviation in thickness; furthermore, the thickness of the steel plate at such defective areas must not be less than its allowable minimum thickness. 2. Defects with a depth exceeding that specified in Paragraph 1, as well as any tearing, bubbles, cracks, scars, folds, embedded scale, inclusions, weld marks, cratering, spatter, etc., shall be removed by grinding. The area to be cleaned and polished should not exceed 30% of the steel plate’s surface area. The pits resulting from polishing should blend smoothly with the base material, with a slope of no more than 1:3. 3. After grinding, if the remaining thickness is not less than its allowable minimum thickness, and the grinding depth is not more than 5% of the nominal thickness or 2 mm (whichever is smaller), welding repair is not required. If the grinding depth is deep, but the remaining thickness still meets the above requirements, it should be resolved through consultation with the designer. Defects beyond those specified in paragraphs (1) to (3) above shall be repaired by welding, but the area and depth that can be repaired must comply with the following requirements: 1. For carbon steel and C-Mn steel: the area of any single repair shall not exceed 200 cm2, and the total repair area shall not exceed 600 cm2, or 3% of the surface area of the steel plate that has been ground (whichever is smaller) ； 2. Low-alloy high-strength steel and Cr-Mo steel: The area of a single repair shall not exceed 100 cm2, the total area shall be less than or equal to 300 cm2, or 2% of the area of the side of the steel plate that has been ground (whichever is smaller) ； 3. The depth allowed for welding repairs shall not exceed 1/5 of the plate thickness ； 4. When the delamination length at the edge of the steel plate is not greater than 25 mm, repair or removal may be omitted ； Delamination with a length greater than 25 mm and a depth greater than 1.5 mm should be ground away. When the grinding depth is no more than 3 mm, welding repair is not required; otherwise, it should be repaired by welding before use. In the same plane, delaminations with a spacing not exceeding 5% of the plate thickness shall be considered as a continuous delamination length.