{"id":5110,"date":"2023-03-10T19:09:29","date_gmt":"2023-03-10T19:09:29","guid":{"rendered":"https:\/\/www.jstconsultancy.cz\/?p=5110"},"modified":"2026-08-01T07:56:48","modified_gmt":"2026-08-01T07:56:48","slug":"nadca-207-and-input-material-quality-control-in-class-1","status":"publish","type":"post","link":"https:\/\/intelligent-kalam.80-240-27-133.plesk.page\/en\/nadca-207-and-input-material-quality-control-in-class-1\/","title":{"rendered":"Nadca 207 and input material quality control in Class 1"},"content":{"rendered":"

As I stated earlier, the material for die casting dies should be categorized in Class 1 or Class 2. According to this classification, testing also belongs to the given semi-finished product (Fig. 1<\/strong>)<\/p>\n

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Fig. 1<\/em><\/strong> \u2013 Example of die design with Class 1 and Class 2 \u00a0categorization<\/em><\/p>\n

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  1. Materials purchased in Class 1<\/u><\/strong><\/li>\n<\/ol>\n

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    We have already explained what materials for die casting dies must meet. However, in order to check that they actually meet this, an initial quality test in the form of impact tests must be carried out for this category of purchase.<\/p>\n

    Why imapct tests? It is basically a test that tells the tool shop in an acceptable time and at an acceptable price that the material is OK<\/strong> or NOK<\/strong>. The tool shop does not have to pay for the material until the tests are done. And if the result is NOK<\/strong>, then the supplier must replace the block or the contract can be withdrawn. Even if we “lose time<\/strong>” according to tool shops, at least in this case we won’t lose money.<\/p>\n

    And if the material is OK<\/strong>, then we are sure that if we do not damagel anything in the next process of manufacturing the die, i.e. not even in the heat treatment, the user will get what he needs.<\/p>\n

    What does it cost us? So above all, if we state in the order that we want material according to Nadca 207, Class 1, then the steel supplier must automatically supply us with the required semi-finished including an allowance for the production of coupons for impact tests. This additional material should be \u00bd” (12.7 mm) thick, as we will then make a test coupon with dimensions \u00bd ” (12.7 mm) x 4 \u00bd” (114.3 mm) x 2 \u00bd” (63 .5 mm). The size is such that the testing laboratory can make 5 impact test samples from it, measuring 10x10x55 mm, see ASTM A370 (Fig. 2<\/strong>).<\/p>\n

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    Fig. 2<\/em><\/strong> \u2013 Layout of samples in the coupon<\/em><\/p>\n

    The cut of the material must not be finished to ensure that what we are testing is part of the block we want to machine. We have to do the finishing ourselves. There should be two of these coupons, one for input tests and the other for heat treatment performance tests.<\/p>\n

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    Fig . 3<\/em><\/strong> \u2013 Drawing of coupon sampling for testing steel in Class 1, Nadca 207, for cross-sections greater than 5″ x 4 \u00bd”<\/em><\/p>\n

    Fig. 4 <\/em><\/strong>\u2013 Drawing of coupons for testing steel in Class 1, Nadca 207, for small cross-sections <\/em><\/p>\n

    Figures 3 and 4<\/strong> show a schematic drawing of material removal on coupons for large and small dimensions of the semi-finished product. According to Nadca 207, all blanks with a Class 1<\/strong> testing requirement and a thickness of at least 2 \u00bd\u201d should be tested.<\/p>\n

    If the steel supplier accidentally delivers a cut material already separated, this is a reason to return the delivery, as he is not authorized to do so.<\/p>\n

    The material for the coupons should be taken from the centre of the delivered block, or blank. Never on the surface area. There it will always show better results than those corresponding to the centre of the block, and that’s what we don’t want. We want a reference on probably the worst variant of block material quality. The resulting shape, which should have those useful properties, is hidden somewhere in the depths, not on the surface.<\/p>\n

    In the event that test coupons from the mother block are not available, the steel supplier must consult the solution about the customer in advance.<\/strong><\/p>\n

    The tool shop does not produce its own samples for impact tests, only the coupons.<\/p>\n

    So the question – what does it cost us can be answered:<\/p>\n