GB/T 26006-2010Aluminium alloys extruded tubes, bars, rods, and profiles used for ships (English PDF)

3.1.3 Specifications

3.1.3.1 Profiles The specifications of the profile are determined, when the supplier and the buyer sign the drawing.

3.1.3.2 Bars

3.1.4 Example of markings The product marking is expressed, in the order of product name, alloy designation, state, specification, standard number. Examples of markings are as follows:

3.3.1.3 Other size deviations shall meet the requirements of GB/T 14846-2008.

3.3.2 Bars

3.3.2.1 Round bar 3.3.2.1.1 Diameter The diameter deviation shall meet the requirements of Table 5.

3.6 Microstructure For the quenched products, it is not allowed for over-burning on the microstructure.

3.7 Ultrasonic flaw detection For the products, which need ultrasonic testing, the supplier and purchaser may determine, through negotiation, the testing location and testing level, AND indicate in the drawing or contract (or order form).

3.8.1 Tubes

3.8.1.1 It is not allowed for cracks or corrosions on the surface of tubes.

3.8.2 Bars

3.8.2.1 It is not allowed for cracks, blisters, or corrosion spots on the surface of bars.

3.8.2.2 Where there is peeling off on the surface of bars, they shall be removed. However, the removal shall not make the deviation of outer diameter (or the diameter of inscribed circle of bars) exceed the allowable range.

3.8.3 Profiles

3.8.3.1 It is not allowed for the presence of cracks, corrosions, or non-metallic press-ins, on the surface of profiles.

3.8.3.2 On the surface of profiles, it is NEITHER allowed for the peeling off, pits, indentations, blisters, bumps, which have a depth larger than the negative deviation of the wall thickness, NOR allowed for scratches, surface roughness, or individual scratch, which have a depth larger than the negative deviation of wall thickness. Within any 1 m length of the profile, the total area of defect shall not exceed 4% of the surface area of profile.

3.8.3.3 It is allowed for the supplier to make trimming of the surface defects of the profiles, along the longitudinal direction, until obtaining a smooth surface. This trimming operation shall not make the deviation of wall thickness of the profile exceed the allowable range.

4.2 Deviation of size

4.2.1 For the cross-sectional size, it shall be measured by a measuring tool, which has an accuracy of not lower than

0.02 mm. For other sizes, it may be measured by the measuring tools, such as ruler, meter ruler, tape ruler, feeler gauge.

4.2.3 The measurement method of planer clearance is as follows: Place the product on the platform, to measure the maximum clearance f, between the product and the platform, as shown in Figure 4.

4.2.4 The measurement method for twisting degree is as follows: For the product, which has a specified testing length (as shown in Figure 5, the AC-segment product), make one end (such as the AB end in Figure 5) of a certain plane (such as the ABCD plane in Figure 5) be in close contact to the platform.

4.3 Mechanical properties The longitudinal tensile properties of the product, under room temperature, shall be tested according to the method, which is specified in GB/T 228.

4.4 Macrostructure The macrostructure of the product shall be tested, according to the method specified in GB/T 3246.2.

4.5 Microstructure The microstructure of the product shall be tested, according to the method specified in GB/T 3246.1.

4.6 Ultrasonic flaw detection The product shall be subject to the ultrasonic flaw detection, according to the method, which is specified in GB/T 6519.

5.1 Inspection and acceptance

5.1.1 The product shall be inspected by the technical supervision department of the supplier, to ensure that, the product quality meets the requirements of this standard and the contract (or order form); meanwhile the quality certificate is filled.

5.1.2 The purchaser shall re-inspect the received products, according to the requirements of this standard. Where the re-inspection result is inconsistent with the requirements of this standard and the contract (or order form), it shall be put forward to the supplier, in the written form, which will be settled between the supplier and the purchaser, through negotiation. For the objections on the surface quality and size deviation, it shall be put forward to, within 1 month from the date of receiving the product.

5.2 Group-batching The products shall be submitted for acceptance in batches. Each batch shall consist of the products of the same designation, sate, specification. The weight of each batch is not limited.

5.5.2 If the size deviation fails, the corresponding product is disqualified. Quantity of products per batch (furnace) Quantity of samples

5.5.3 When the tensile properties at room temperature fails, it is judged as follows:

5.5.3.1 From this batch (furnace) (including those which are disqualified in the original inspection), take another double quantity of specimens, to carry out test again (for the product of H112 state, it may be tested again according to the requirements of 5.5.3.2). If the re-test results all qualified, this batch (furnace) of products are qualified. If there is still disqualified item in the re-test results, this batch (furnace) of products are disqualified.

5.5.4 When the macrostructure is disqualified, it is judged as follows:

5.5.4.1 When the product is judged as disqualified, due to metallurgical defects, such as cracks or non-metallic inclusions, this batch of product is disqualified. However, it is allowed to carry out grade-B ultrasonic testing piece by piece, only those qualified is delivered.

5.5.4.3 If it is disqualified due to delamination, tail shrinkage, or coarse crystal ring, it is allowed to carry out re-inspection after cutting a segment, until it is qualified. For the other products in this batch, it shall, according to the maximum length of the aforementioned defect distribution, cut the tails OR inspect piece by piece, only those qualified is delivered.

5.5.5 When the microstructure is disqualified, if the melting number of the product can be distinguished, the corresponding furnace number of heat treatment fails; whilst the other furnace numbers are inspected one by one, only those quality is delivered. However, if the furnace number cannot be distinguished, this batch of products are disqualified.

5.5.6 If the ultrasonic testing fails, this piece of product is disqualified.

6.1 Marking

6.1.1 On the extruded front end of the product, which had passed the inspection, print the following markings (it may also tag or label each bundle of products).

6.1.2 On the extruded tail end of the product, which had passed the inspection, apply the "W" sign (or paste tag).

6.1.3 The marking of the packing box of the product shall meet the requirements of GB/T 3199.

6.2 Packaging, transportation, storage

6.2.1 Packaging, transportation, storage of tubes The tubes are not greased. For all tubes, which have a diameter of less than or equal to

50.00 mm, AND the tubes, which have a diameter of more than

50.00 mm and wall thickness of less than

7.00 mm, they shall be box-packed; the weight of each packing box shall not exceed 1000 kg.

6.2.2 Packaging, transportation, storage of bars The bars are not greased. For the bars which have a diameter of less than

50.00 mm, they shall be packed in a packing box, which has been lined with packing materials; the weight of each packing box shall not exceed 1000 kg. Other bars are bundle-packed in bare state. Where it needs applying grease OR there is other special requirement, it may be determined, through negotiation, between the supplier and the purchaser, AND indicated in contract (or order form). Other requirements shall meet the requirements of GB/T 3199.

6.3 Quality certificates Each batch of products shall be accompanied with the product quality certificate, on which it shall indicate the following.