1 job description

1. 1 task source

With the development of China's national economy, China's aluminum and aluminum alloy extrusion profiles have developed rapidly and exported to the United States, Europe and other countries in the world. In order to meet the needs of foreign markets, at the annual meeting of the National Technical Committee for Standardization of Nonferrous Metals held in Changsha on June 2-5, 2004, while revising GB/T6892-2000, this standard was revised to make it consistent with the newly revised GB/T 6888. The National Technical Committee for Standardization of Nonferrous Metals issued the task of drafting this standard in documentNo.. Nonferrous Metals Standardization Committee (2006) 13, editor-in-chief of Southwest Aluminum (Group) Co., Ltd. This standard is mainly based on the original GB/T 14846-93, and refers to European EN755.9- 1998 Allowable Deviations of Dimensions and Shapes of Aluminum and Aluminum Alloy Bars, Pipes and Profiles and EN 12020.2-2006554.

1.2 Compilation Group

The drafting group of this standard was established at the annual meeting of the National Technical Committee for Standardization of Nonferrous Metals held in Changsha on June 2-5, 2004, with Southwest Aluminum (Group) Co., Ltd. as the editor-in-chief, and China Institute of Standard Metrology and Quality of Nonferrous Metals Industry and Northeast Light Alloy Processing Co., Ltd. as participants.

1.3 main workflow

1.3. 1 The first draft of this standard was put forward in September 2005, and the standard seminar was held in Chengdu on September 23, 2005. According to the spirit of Chengdu seminar, the standard draft for comments was put forward.

1.3.2 This standard was sponsored by the National Technical Committee for Standardization of Nonferrous Metals and held in Guangzhou on April 8 ~ 10, 2006. There were 70 units and 130 representatives attending the meeting, and the participants seriously discussed the draft for comments. According to the spirit of Guangzhou pre-trial meeting and the discussion opinions on the draft for comments, the draft of this standard is proposed.

2 main contents of the standard

2. 1 definition

According to the spirit of Guangzhou Pre-trial Meeting, in order to accurately understand and explain the circumscribed circle diameter of profile, the definition of "circumscribed circle diameter" was added.

2.2 Classification and grading

2.2. 1 alloy classification

2.2. 1. 1 original GB/T 14846-93 divides the profiles into four categories: A, B, C and D. Because the C-type precision profiles are mainly building profiles, the size deviation of building profiles is in GB/T5237. 1 "Aluminum alloy building profiles No.656"

2.2. 1.2 According to the original standard, profiles are divided into three categories: high magnesium profiles, cemented carbide profiles and soft alloy profiles. In the United States, profiles are divided into high magnesium alloy profiles (magnesium content ≥3%) and non-high magnesium alloy profiles. In Europe, profiles are divided into cemented carbide profiles and soft alloy profiles, and high magnesium alloy profiles with magnesium content ≥2.5% and 2XXX.

2.2. 1.3 in order to meet the demand of American and European markets at the same time, this standard divides the profiles into cemented carbide profiles and soft alloy profiles, among which high magnesium alloy profiles with magnesium content ≥3.0% and 2XXX and 7XXX series alloy profiles are classified as cemented carbide profiles, while others are soft alloy profiles.

2.2.2 Index classification

Like the original standard, this standard still divides the section size, curvature, waviness, twist and slope into three levels: ordinary level, high precision level and ultra-high precision level.

2.3 Section Size and Deviation

2.3. 1 architecture

Europe * * is more suitable than the United States for dividing the index system of section size and allowable deviation, so this standard refers to the index system of Europe * * to specify the section size and allowable deviation.

2.3.2 Wall thickness dimension and deviation

2.3.2. 1 wall thickness grouping

In this standard, the wall thickness was originally divided into two groups, A and B. At the Guangzhou pre-trial meeting, the representative thought that it should be consistent with the European body. Therefore, the wall thickness is divided into three groups: a, b and C.

2.3.2.2 Ⅰ material (cemented carbide profile)

2.3.2.2.1adopts the index of EN755.9- 1998 as the high-precision index of this standard.

2.3.2.2.2 For ordinary grade, according to Japanese jis 4 100 "Aluminum and Aluminum Alloy Extruded Profile" standard, the ordinary grade is about 1.5 times that of high-precision grade. Therefore, the high precision index value is multiplied by 1.5 as the normal level.

2.3.2.2.3 For the ultra-high precision grade, the index value of the ultra-high precision grade is divided by 1.5 as the ultra-high precision grade. If the individual indexes of groups A, B and C in the ultra-high precision grade can't reach the indexes of non-high magnesium alloys in the ANSIH35.2 standard, appropriate modification shall be made to make them reach the indexes in the ANSIH35.2 standard, so that the ultra-high precision grade in this standard is higher than that in ANSIH.

2.3.2.3 Ⅱ material (soft alloy profile)

2.3.2.3.1adopts the index of EN755.9- 1998 as the high-precision index of this standard;

2.3.2.3.2 For ordinary grade, according to Japanese jis 4 100 "Aluminum and Aluminum Alloy Extruded Profile" standard, the ordinary grade is about 1.5 times that of high-precision grade. Therefore, the high precision index value is multiplied by 1.5 as the normal level.

2.3.2.3.3 For the ultra-high precision grade, the index value of the ultra-high precision grade is divided by 1.5 as the ultra-high precision grade. If the individual indexes of groups A, B and C in the ultra-high precision level can't reach the indexes of non-high magnesium alloys in the standard of ANIH 35.2, appropriate modification shall be made to make them reach the indexes of the standard of ANIH 35.2, so that the ultra-high precision level of the standard is higher than that of ANIH. The ultra-high precision index of this standard is also higher than the standard level of EN 12020.2-200 1.

2.3.3 Allowable deviation of non-wall thickness dimension and section.

2.3.3.1Ⅰ material (cemented carbide profile)

2.3.3. 1. 1 adopts EN755.9- 1998 as the high-precision index of this standard.

2.3.3. 1.2 For the ordinary grade, in the Japanese jis 4 100 standard, the ordinary grade is about 1.5 times that of the high grade. In this standard, if the high-precision index value is multiplied by 1.5 as the ordinary level, its value is far from the ordinary level index of GB/T 14846-93, so the high-precision index value is multiplied by 1.2 as the ordinary level index. This is similar to the common index of the original GB/T 14846-93.

2.3.3. 1.3 For ultra-high precision indicators, if the index value of high-precision indicators is divided by 1.5 as ultra-high precision indicators, its value is far from the original GB/T 14846-93, so the index value of high-precision indicators is divided by 1.7. This is similar to the original ultra-high precision index of GB/T 14846-93. The index of medium-high magnesium alloy is stricter than ANSIH35.2, which is equivalent to other alloys. Index higher than EN755.9-1998.

2.3.3.2 Ⅱ material (soft alloy profile)

2.3.3.2.1adopts the index of EN755.9- 1998 as the high-precision index of this standard.

2.3.3.2.2 For ordinary grade, in Japanese jis 4 100 "Extruded Aluminum and Aluminum Alloy Profile" standard, the ordinary grade is about 1.5 times of the high-precision grade. In this standard, the high-precision index value multiplied by 1.2 is used as the common level for Class I materials, and the high-precision index value multiplied by 1.2 is also used as the common level index for Class II materials. This is basically equivalent to the general index of the original GB/T 14846-93.

2.3.3.2.3 For the ultra-high precision grade, in the Japanese jis 4 100 standard, the high precision grade is about 1.5 times that of the ordinary grade. Although the high-precision index value divided by 1.7 is used as the ordinary grade for Class I materials in this standard, if the high-precision index value divided by 1.7 is also used as the ultra-high precision index for Class II materials, it is much stricter than the ultra-high precision grades of American ASTMB22 1 and original GB/T 14846. Therefore, dividing the high-precision index value by 1.5 is the ultra-high-precision index. In this way, the ultra-high precision index of type II wood is slightly higher than that of American ASTMB22 1, and basically equivalent to the original GB/T 14846-93.

2.3.3.3's interpretation of clause 4. 1.2.7 (non-wall thickness dimension deviation of hollow profile);

For the hollow profile shown in Figure 4 and Figure 5, if it contains a space part, its deviation should be looser than the solid part, but after all, it is not the opening size, so its deviation should be stricter than the opening size. In ANSIH35.2 and Japanese standards, when E≤6mm, the deviation of hollow dimension is equal to the deviation of solid dimension. Therefore, the width of the hollow dimension h is the allowable deviation in the four columns of 6 < e ≤ 15 corresponding to the height d, indicating that the deviation of the hollow dimension is stricter than the solid dimension and slightly looser than the opening dimension. In this standard, because the deviation of the space-time center size of E≤20mm is equal to the deviation of the solid size, the allowable deviation of the width d corresponding to four columns with 20 < E ≤ 30 is specified for the height of the hollow size H.

2.3.4 Angle and deviation of cross section

2.3.4. 1 For the first kind of wood, the angular deviation is the same as the original GB/T 14846.

In 2.3.4.2, the angle deviation of the original precision profile is strictly required to be the second-class material, but now the precision profile is classified as the second-class material, so it is stricter to regard the angle deviation of the original precision profile as the second-class material than the original GB/T 14846 standard.

In the standard of 2.3.4.3 EN 755.9-1998, the angle deviation is 0.5 ~ 0.9. In the standard EN 12020-200 1, the angular deviation is 0.3 ~ 0.5. In the American ANIH 35.2 standard, the angular deviation is 1 ~ 1.5. Therefore, the current high-precision index is equivalent to the standards of EN755.9- 1998 and ANIH 35.2, and the ultra-high-precision index is equivalent to EN 12020-20065438+.

2.3.5 Allowable deviation of chamfer radius, fillet radius and section.

2.3.5. 1 chamfer radius r and allowable deviation

2.3.5. 1. 1 original GB/T 14846 is equivalent to American ANSIH35.2 standard. Because ANSIH35.2 does not reflect the allowable deviation relationship between chamfer radius and wall thickness, but the European standard does, the European standard is adopted in this revision.

2.3.5. 1.2 because the allowable deviation of chamfering radius in ANSIH35.2 standard is stricter than that in Euro * * * * this standard adopts more stringent gears in EN755.9- 1998 as the allowable deviation of chamfering radius of Class I materials, and adopts EN12020-20066.

2.3.5. 1.3 this standard is equivalent to European standards EN755.9- 1998 and EN 12020-200 1, and is equivalent to American standard ANSIH35.2.

2.3.5.2 fillet radius r and allowable deviation

2.3.5.2.1original GB/T 14846 is equivalent to American ANSIH35.2 standard, and the deviation is 0.4 when the fillet radius R≤5. Now the American ANSIH35.2 standard has been revised. When the radius r of fillet is less than or equal to 5, the deviation is 0.5, which conforms to European standards EN755.9- 1998 and EN 12020-200 1. Therefore, this standard adopts 0.5.

2.3.5.2.2 The level of this standard is equivalent to ANSIH35.2 in the United States, EN755.9- 1998 and EN 12020-200 1 in Europe.

2.3.6 Allowable deviation of surface clearance and cross section

2.3.6. 1 For the clearance between curved surfaces, the American ANSIH35.2 is inconsistent with the methods specified in European standards EN755.9- 1998 and EN 12020-200 1. This standard adopts the European standard system and is directly adopted.

This standard in 2.3.6.2 is the same as the European standard, but slightly lower than the ANSIH35.2 in the United States.

2.4 Bending degree

2.4. 1 This standard clearly defines the curvature of profiles as longitudinal curvature, longitudinal transverse curvature and longitudinal waviness.

2.4.2 The original GB/T 14846- 1993 requires the degree of curvature and waviness. However, in the European standard and American standard, only curvature is required, and curvature measures the gap value per 300mm length and the maximum gap value over the whole length of L meter. In fact, in the advanced standards of Europe and America, measuring the bending value per 300mm length is actually the requirement of waviness. Therefore, when revising the standard, only the longitudinal curvature and transverse curvature of the maximum length are tested, and the index of every 300mm in the original curvature is put into the waviness requirement. Combined with ripples.

2.4.3 The definitions of side curvature and waviness are added, and the schematic diagram of side curvature is given.

2.4.4 The bending requirements of EN 755.9-1998 standard are: not more than 0.6mm every 300mm and not more than 1.5mm every1000 mm..

2.4.5 The standard bending degree of Euro * * * EN 12020-200 1 is: not more than 0.3mm every 300mm, and the total length is specified in the following table.

Bending deviation of L meters on the following full length, mm

≤ 1 > 1~2 >2~3 >3~4 >4~5 >5~6 >6

0.7 1.3 1.8 2.2 2.6 3.0 3.5

2.4.6 American bending standards are shown in the following table:

Explain the requirements of circumscribed circle diameter, wall thickness and curvature.

O >12.5 ≤ 2.516mm/1 mm

> 2.5 4 mm/1 mm

TX5 10, tx511 >12.5 ≤ 2.54 mm/1mm.

> 2.5 1 mm/1 mm

Other states ≤ 40 ≤ 2.54 mm/1 mm.

> 2.5 1 mm/1 mm

> 40 all 1 mm/1 mm

2.4.7 According to the original index of GB/T 14846 and the standards of ANSIH35.2, EN755.9- 1998, EN 12020-200 1, the bending degree of this standard is determined by longitudinal bending degree, longitudinal waviness. After revision, the high precision level of this standard is equivalent to ANSIH35.2 in the United States, slightly higher than the standard EN755.9- 1998, and the ultra-high precision level of this standard is basically equivalent to the standard EN 12020-200 1.

2.5 Plane clearance

2.5. 1 The advanced level of this standard is equivalent to the standard of EN755.9- 1998.

2.5.2 The general level of this standard is formulated with reference to the proportion of the general level in the original GB/T 14846, which is slightly stricter than the general level in the original GB/T 14846.

2.5.3 The ultra-high precision level of this standard is equivalent to the standard EN 12020-200 1. For columns with a width greater than 300mm, the index of high-precision level is reduced by 1.2 times.

2.6 twist

2.6. 1 The high precision level of this standard is equivalent to the standard EN755.9- 1998, and its index is much higher than the ultra-high precision level index in GB/T 14846.

2.6.2 The ordinary level of this standard is based on the lower limit (the strictest) of the deviation range of the ordinary level in the original GB/T 14846 as the ordinary level index of this standard, so the ordinary level of this standard is more stringent than that in the original GB/T 14846.

2.6.3 The ultra-high precision grade of this standard refers to EN 12020-200 1 standard. For the columns with no data in the standard EN 12020-200 1, the index of high precision level is reduced by 1.2 times.

2.6.4 The distortion of this standard is much higher than the standard level of ANSIH35.2.

2.7 Shear slope

The cutting inclination of profile is consistent with the original GB/T 14846-93.

2.8 Length deviation

According to the spirit of Chengdu seminar, the length deviation is modified to "length deviation of cut-to-length profile +20mm".

3 standard level analysis

For the high precision or ultra-high precision level of this standard, please refer to EN755.9- 1998 Allowable Deviations of Dimensions and Shapes of Aluminum and Aluminum Alloy Bars, Pipes and Profiles and EN12020.2-20016060 and 6063 Aluminum Alloy Precision Profiles.

4 Expected effect

This standard is mainly based on the original GB/T 14846-93. Reference is also made to European EN755.9- 1998 "Allowable Deviations of Dimensions and Shapes of Aluminum and Aluminum Alloy Bars, Pipes and Profiles", EN 12020.2-200 1, 6060 and 6063 "Allowable Deviations of Dimensions and Shapes of Aluminum Alloy Precision Profiles" and the main contents.