GB 11450.1-1989 Hollow metallic waveguides Part 1: General requirements and measurement methods
Some standard content:
UDC621.646 : 621.372.8
【Genuine】GB11450.1-1989【Genuine GB national standard full text download】GB
National Standard of the People's Republic of China
GB11450.1-89
Hollow metallic waveguides
Part 1:General requirements and measuring methodsPublished on March 31, 1989
Implemented on March 1, 1990
Published by the State Administration of Technical Supervision
National Standard of the People's Republic of China
Hollow metallic waveguides
Part 1:General requirements and measuring methods methodsGB11450.189
IEC153-1
When necessary, this standard shall take into account GB2421 "General Rules for Basic Environmental Testing of Electrical and Electronic Products" and shall be used in conjunction with GB
11449 "Waveguide Flanges". When the general requirements of this standard are inconsistent with the relevant waveguide specifications, the relevant waveguide specifications shall prevail. Scope
This standard applies to hollow metal waveguides used in electronic equipment. Purpose
The purpose of this standard is to specify for hollow metal waveguides: a.
Details necessary to ensure compatibility and, in essence, interchangeability; test methods;
Uniform requirements for electrical and mechanical properties.
This standard is equivalent to IEC153-1 "Hollow Metal Waveguides Part 1: General Requirements and Measurement Methods" (first edition in 1964)\. 1 General Provisions
1.1 Terminology)
Terminology shall comply with the provisions of GB2900.1 (Basic Terminology of Electrical Terminology). 1.2 Model Nomenclature
The model of the waveguide included in this standard consists of the following parts: letter code B for waveguide;
b. Letter code indicating the shape of the internal cross-section of the waveguide: J - rectangular;
B - flat rectangle,
Z - medium flat rectangle;
F - square
Y - round.
Instructions for Use
1) This standard omits the content in the foreword of IEC153-1 that does not recommend waveguide materials, and recommends several materials for selection based on domestic conditions (see Appendix B).
2) This standard omits the definition of test procedures in the IEC153-1 terminology, and compiles Appendix A (Supplement) \ Quality Assurance Provisions "as product acceptance criteria
3) This standard does not directly adopt IEC 153 model naming method, but the Chinese phonetic alphabet for model naming. However, the IEC153 model is still retained in the product specification for comparison.
Approved by the Ministry of Electronics Industry of the People's Republic of China on March 4, 1989 and implemented on March 1, 1990
GB11450.189
c. A number that characterizes the specifications of a specific waveguide. The number represents the frequency characteristics of the waveguide and approximately represents the geometric mean frequency of the main mode frequency range in multiples of 100MHz. For example: B/100 represents an ordinary rectangular waveguide of 22.860mm×10.160mm, with a main mode center frequency of approximately 10GHz. 1.3 Standard atmospheric conditions for testing
1.3.1 Unless otherwise specified, all tests shall be carried out under the "standard atmospheric conditions" specified in GB2421 "General Rules for Environmental Testing Procedures for Electrical and Electronic Products".
1.3.2 Before making any measurement, the waveguide shall be placed at the measuring temperature for a sufficient period of time so that the entire waveguide can reach this temperature.
1.3.3 When measurements are not made under the specified temperature conditions, the measurement results shall be corrected to the values of the specified temperature if necessary. The ambient temperature during the measurement shall be stated in the test report. 1.4 Appearance Inspection
The structure and wall thickness of the waveguide shall be uniform and it shall be straight and smooth from beginning to end. The surface of the waveguide shall be free of burrs, cracks, mold marks, shatter marks, dirt, grease or other irregularities.
As a rule of thumb, the inner and outer surfaces of the waveguide shall have a clean and bright appearance. 2 Mechanical Requirements
2.1 Dimensions
2.1.1 Overview
The dimensions and tolerances of the waveguide shall conform to the values specified in the relevant specification diagrams. The nominal dimensions of the internal and external cross-sections of the waveguides shall be given in such a way that when the first digit of the value is 3 to 9, the value is given to 4 significant figures, and when the first digit of the value is 1 or 2, the value is given to 5 significant figures. In principle, the internal nominal dimensions shall be rounded to the nearest 0.001 mm and the external nominal dimensions shall be rounded to the nearest 0.01 mm. NOTE When these principles are applied, for rectangular waveguides, except for small waveguides, the joint of two imaginary waveguides with nominal dimensions will produce a calculated reflection loss of less than -70 dB. Unless otherwise specified, the following dimensions shall be given in the relevant specification diagrams: a.
Nominal dimensions of the inner surface;
Tolerances of the inner dimensions,
Maximum radius of the inner corner of a rectangular waveguide
Nominal wall thickness,
Maximum eccentricity;
Nominal dimensions of the outer cross-section;
Tolerances of the outer dimensions;
Minimum and maximum radius of the outer corner of a rectangular waveguide; Ellipticity of a circular waveguide.
2.1.2 Ordinary rectangular waveguides
2.1.2.1 Internal dimensions
The standard ratio between the height and width of the inner cross-section is 1:2 (for some waveguide specifications, the ratio between the height and the width is slightly different from this ratio. Since these waveguides are widely used, these waveguides are still selected). The tolerances for the width and height dimensions shall be given in the relevant specification diagrams. The inner corner radius shall comply with the provisions of the relevant specification diagrams. Note: If a higher precision tolerance is required, it is recommended that the tolerance be taken as width ± 10 · 2.1.2.2 Wall thickness 1
The nominal wall thickness is defined as half of the difference between the nominal external dimension and the nominal internal dimension. Its value should be given in the relevant specification chart for reference.
2.1.2.3 Eccentricity
GB11450.1—89
Eccentricity is defined as half of the difference between the measured thickness of two opposite walls. If not otherwise specified, the eccentricity should not exceed 10% of the nominal wall thickness. To determine the eccentricity, the wall thickness should be measured at the place where the most unfavorable result is produced. 2.1.2.4 External dimensions
The nominal values of height and width and their tolerances should be given in the relevant specification chart. For some large-sized waveguide specifications, the external dimensions are not specified due to different manufacturing processes used. The radius of the outside corner (r2) shall be within the following range: T2mia = 0.5t
T20x = T2la + 0.5mm
Where: t is the nominal wall thickness.
2.1.2.5 Rectangularity of the cross section
The dimensional requirements of 2.1.2.1 and 2.1.2.4 do not control the rectangularity of the cross section. The permissible rectangularity deviation is limited by the requirement that the shape of the inner (outer) section conform to the following condition, that is, the requirement that the actual inner (outer) section should be contained within the range between the specified maximum and minimum inner (outer) rectangles. An example of a suitable method for checking rectangularity is as follows. Inspection of the inner section
A plug gauge with the following specified dimensions shall pass through the waveguide without obstruction. When pulling the plug gauge through the waveguide, care must be taken to keep the plug gauge exactly perpendicular to the waveguide axis.
The dimensions of the plug gauge are as follows:
①The nominal dimension of the cross section is the nominal diameter of the waveguide minus 1.1 times the diameter tolerance; ②The tolerance of the cross section is + 0, + 0.1 times the tolerance of the waveguide diameter; ③The verticality of the side is the deviation should not exceed 3×10-*radians; ④The length is 0.2 times the internal width of the waveguide. b. Inspection of the external cross section
The inspection of the external cross section is to pass the waveguide through a standard gauge with a rectangular cross-sectional diameter. The diameter dimensions of the standard gauge are as follows:
①The nominal dimension of the cross section is the nominal external dimension of the waveguide plus 1.1 times the dimension tolerance; ②The tolerance of the cross section is + 0, + 0.1 times the tolerance of the external dimension of the waveguide cross section; ③The verticality of the side is the deviation should not exceed 3×10-degrees. 2.1.3 Flat rectangular, medium flat rectangular and square waveguides\)2.1.3.1 Internal dimensions
Except for special models, the internal width of flat rectangular and medium fan-shaped rectangular waveguides shall be equal to the internal width of the corresponding ordinary rectangular waveguide specifications.
The standard ratio between the height and width of the internal section of flat rectangular, medium flat rectangular and square waveguides is 1:8.33, 1:4 and 1:1 respectively. However, for small-sized flat rectangular waveguides, it is recommended to use the circle height. The tolerance of the height and width of the inner surface of the waveguide shall comply with the provisions in the relevant specification chart. 2.1.3.2 Wall thickness
Should follow the same principle as ordinary rectangular waveguides. 2.1.3.3 Eccentricity
Should follow the same principle as ordinary rectangular waveguides. 2.1.3.4 External dimensions
Adoption instructions:
1 This standard omits the content of the metric and imperial conversion rules for dimensions in this clause. 2] This standard adds the relevant content of medium flat rectangular and square waveguides. 3
GB11450.189
The tolerances of the height and width of the waveguide outer surface shall comply with the provisions in the relevant specification diagrams. 2.1.3.5 The rectangularity of the cross hub surface
shall follow the same principles as for ordinary rectangular waveguides. 2.1.4 Circular waveguide
2.1.4.1 The internal dimensions
diameter and its tolerances shall comply with the provisions in the relevant specification diagrams. b. Ellipticity
Ellipticity "E\" is defined as:
E = Deur - Dae
Where: D-nominal inner diameter;
D——maximum internal dimension measured;
Din——minimum internal dimension measured.
Ellipticity shall not exceed the requirements specified in the relevant specification chart. 2.1.4.2 Wall thickness
For wall thickness, the same principle as for ordinary rectangular waveguides shall be adopted. 2.1.4.3 Eccentricity
For eccentricity, the same principle as for ordinary rectangular waveguides shall be adopted. 2.1.4.4 External dimensions
External dimensions The nominal values of external dimensions and their tolerances shall be as specified in the relevant specification tables. For some large-size waveguide specifications, the external dimensions are not specified due to the different manufacturing processes used. 2.2 Other Mechanical Requirements
2.2.1 Curvature
Bend is defined as the maximum deviation between the actual axis of the waveguide and a straight line connecting two points of a specified length on this axis. The bend is measured on the outer surface of the waveguide. For a length of 10 times the internal width, the external bend shall not exceed 10 times the tolerance specified on the internal width. For a length of 50 times the internal width, the external bend shall not exceed 40 times the tolerance specified on the internal width. To determine the bend on the outside of the waveguide, the waveguide shall be placed so that gravity does not affect the amount of bend. 2.2.2 Torsion
Torsion is defined as the rotation of the waveguide cross section about the longitudinal axis over a specified length. The torsion rate shall not exceed:
For waveguides with an internal width equal to or greater than 100 mm, the torsion shall not exceed 0.5° per meter of length. When the waveguide When the internal width is less than 100mm, the twist shall not exceed 0.5° for every 10 times the internal width. The cumulative twist shall not exceed 2° over a length equal to 50 times the internal width of the waveguide. The twist direction shall not be regular in a batch of waveguides.
2:2.3 Surface roughness 1)
The roughness of the inner surface of the waveguide shall not exceed the provisions of Table 1. Waveguide inner width. Or inner diameter D
Less than 100
Equal to and greater than 100
GB 11450.1—89
Table 1 Maximum allowable values of surface roughness
Arithmetic mean deviation of profile R.
Aluminum and aluminum alloys
Steel and pot alloys
Surface roughness should be measured at 150 mm from both ends of the waveguide and at three locations in the middle. The measurement method can be arbitrary. 2.2.4 Internal stress
The waveguide should be cut with a saw. The cutting process must be carefully controlled to avoid deformation due to cutting, and it is recommended to use a fine Toothed high-speed saw. After cutting, the tolerance of the cross section of the waveguide should still be within the specified range. 3 Electrical Test
3.1 Attenuation
The measurement of waveguide attenuation should be carried out at a frequency of 1.5 times the cut-off frequency for rectangular waveguides (ordinary rectangular, flat rectangular and medium flat rectangular waveguides); for square waveguides, it should be carried out at a frequency of 1.3 times the cut-off frequency; and for circular waveguides, it should be carried out at a frequency of 1.2 times the TE.(H) cut-off rate. The measurement accuracy should be within ±10% of the required attenuation decibel value. If not otherwise specified, the attenuation value should not exceed 1.3 times the value calculated for the ideal surface and the standard resistivity of the relevant material. The attenuation should be calculated according to the following formulas, but these formulas are not applicable to the calculation of attenuation on thin coating surfaces. Rectangular (including square) waveguide (TEo (H) mode) \): a = 2.3273
Where: - Resistivity of non-magnetic metal on the inner wall; Pe
Resistivity of copper (1.7241×10~8Q·m); a--internal width, mm;
b-internal height, mm;
149.9 GHz);
fe-TEIo (Ho) mode cutoff frequency (
f-frequency to calculate attenuation.
Circular waveguide (TEu (Hu) mode)):
Adoption instructions:
1) IEC1531 has not yet determined the requirements for surface roughness, but this standard has made provisions. 2) IEC1531 does not include the requirements for medium-sized fan rectangular and square waveguides, and this standard has made supplements. ·（1）
（2）
Wherein, p--resistivity of non-magnetic metal of inner wall, GB11450.189
A-resistivity of steel (1.7241×10-*g·m); D--inner diameter, mm,
f.--cutoff rate of TEn(H,) mode (175, 703D
f--frequency to calculate attenuation,
3.2 Inhomogeneity of characteristic impedance
GHz),
3.2.1 The purpose of this test is to determine the periodic variation of characteristic impedance along the length of waveguide, which may cause unacceptable internal reflection. The requirement of characteristic impedance inhomogeneity is determined by negotiation between supplier and buyer. As an example, a suitable measurement method is given in Section 3.2.2. 3.2.2 The inhomogeneity of the characteristic impedance of the waveguide along its length shall be measured at the frequencies specified in 3.1. During the measurement, a non-reflecting terminal load is moved along the waveguide under test. The sliding terminal load must be designed so that it does not eliminate the inhomogeneities of the waveguide.
The incremental reflections due to the inhomogeneities may be detected by means of a fixed probe and a nulling indicator: or by means of the waveguide bridge method.
The measurement error shall not exceed 20 % of the value of the measured reflection coefficient. NOTE When the needle method is used, a second measurement shall be made with the probe moved by one wavelength. When the bridge method is used, care shall be taken to ensure that the unbalance of the bridge is always small. If the incremental reflections are not greater than the residual unbalance of the bridge, the incremental reflections orthogonal to this unbalance will be difficult to distinguish.
4 Additional Tests
4.1 Airtightness
This test shall only be carried out if it is not expected that the materials used or the manufacturing process will ensure adequate airtightness. The airtightness requirement (slip rate) shall be agreed upon by both the supplier and the buyer. This standard recommends the "pressure drop method during the test time", but other methods may also be used. 4.1.1 Test method (pressure drop method during the test time) This test should be performed on the assembled waveguide assembly. The air leakage rate and air pressure drop rate of the sealed waveguide assembly can be determined by measuring the change in the internal pressure of the waveguide assembly during the test time. 4.1.1.1 Definition of terms and symbols
Gas rate: The volume of air leaked from a waveguide assembly under constant pressure within a specified time, corrected to standard atmospheric conditions. .
Note: ① The preferred unit for expressing the leakage rate is cubic meter of air at standard pressure per second. ② During the test, the air pressure inside the waveguide element may drop, and the ambient air pressure outside the waveguide may also fluctuate. In all tests, the errors caused by small changes in the force caused by the above effects during the test period are negligible. Gauge pressure: refers to the air pressure displayed by the barometer, that is, the air pressure value that exceeds the external atmospheric pressure. Standard atmospheric conditions: humidity is 20℃, and the air pressure is 101.3kPa (-atmosphere). P,1. Standard atmospheric pressure (one atmosphere). Pi - atmospheric pressure at the beginning of the test.
Pr - atmospheric pressure at the end of the test.
Instructions for use
1) IEC153-1 does not specify the requirements for characteristic impedance non-uniformity, while this standard stipulates that its requirements shall be agreed upon by the supplier and the buyer. 2) IEC153-1 does not specify the airtightness requirements, while this standard stipulates that it shall be agreed upon by the supplier and the buyer. 37IEC153--1 The test method has not been determined. This standard recommends and quotes the "pressure drop method during the test time" in IEC261 (1968 edition). 6
Pa——Gauge pressure at the beginning of the test.
Po2——Gauge pressure at the end of the test.
GB11450.1-89
Pi——Absolute air pressure in the waveguide assembly corrected to the standard temperature (20°C) at the beginning of the test. Pz——Absolute air pressure in the waveguide assembly corrected to the standard temperature (20°C) at the end of the test. P.—Air pressure drop corrected to the standard temperature (20°C) during the test time. T,——The temperature of the gas in the waveguide at the beginning of the test. T—The humidity of the gas in the waveguide at the end of the test. V The combined volume of the waveguide assembly and the pressure measuring instrument, V.—The gas volume loss caused by the measuring instrument. VL—The volume of leaked gas under standard atmospheric conditions. 4.1.1.2 Test procedure
Use air to pressurize the waveguide assembly to the specified meter pressure and cut off the air supply. ..
Down.
Wait long enough for the internal pressure of the waveguide to stabilize, then record the meter pressure Pa1, ambient pressure P and ambient temperature T. At the end of the test, record the meter pressure Po2, ambient pressure P, and ambient temperature T:. According to the following formula, convert Po: and Po to the absolute pressure value inside the waveguide corresponding to a temperature of 20°C: P=(P:+Po)
P; = (P: + Pon) T, + 273
Calculate the temperature-corrected air pressure drop during the test period by the following formula: Pa=P,-P2
Use the following formula to convert the air pressure loss into the volume of leakage: Vi:
Leakage rate=V,/t (t is the test time in seconds). 4.1.1.3 Test conditions
The specific test conditions shall be agreed upon by the supplier and the buyer. However, the following conditions shall be adopted with priority: The air pressure drop in the waveguide shall not exceed 5% of the absolute air pressure P at the beginning of the test. a.
The maximum allowable ratio of the volume of the measuring instrument to the volume of the waveguide assembly shall be 0.1. The maximum allowable change in ambient temperature shall be 5°C. The meter air pressure Po of the test shall be 101.3 kPa. The test time shall be 8.64×10°s (one day). GB 11450.189
Appendix A
Quality Assurance Provisions
(Supplement)
Quality assurance provisions are an important part of the standard. In order to ensure product quality, this appendix is specially supplemented on the basis of equivalent adoption of IEC153-1.
A1 Inspection Responsibilities
The waveguide shall be inspected by the technical inspection department of the manufacturer and shall be accompanied by a qualified mark to ensure that the finished waveguide meets the requirements of this standard and the corresponding waveguide specifications. The ordering party has the right to re-inspect any item of the product in accordance with the provisions of this standard. The manufacturer shall maintain measuring instruments and test equipment with sufficient accuracy and quantity so that inspections can be carried out in accordance with the provisions of this standard. A2 Inspection Categories
The inspection categories specified in this standard are as follows:
Material inspection;
Identification inspection;
Quality-Consistency inspection.
A3 Material inspection
Material inspection shall be proved by checking relevant data. Before the waveguide is manufactured, it shall be verified that the waveguide material complies with the relevant standards (see Appendix B).
Qualification test
Qualification test shall be carried out in a nationally recognized testing unit. The qualification test shall be carried out on samples produced by the equipment and production procedures used in normal production.
A4.1 Sample size
Four samples of each model shall be taken for qualification test. A4.2 Test procedure
Qualification test shall be carried out in the order specified in Table A1. All samples shall be subjected to one group test. Then the samples shall be divided into two groups of 2 samples each and subjected to the test of each group.
Table A!
【Group (all samples)
Appearance, cross-sectional dimensions, eccentricity, rectangularity or ellipticity and internal stress 1 Group (two samples)
Surface roughness
【Group (two samples))
Imperature resistance unevenness
Air tightness"
Identification testbzxZ.net
1.4, 2.1 and 2.2. 4
GB 11450.1--89
Note: 1) In a group 1 inspection, the various tests shall be carried out on the waveguide (i.e. waveguide assembly) with the flange installed. 2) The airtightness test shall be carried out only when it is considered necessary. A4.3 Number of failures
One or more failures shall be grounds for refusing to grant qualification. A5 Quality consistency inspection
A5.1 Batch inspection
The batch inspection of products shall consist of group A and group B inspections. A5.1.1 Inspection batch
An inspection batch shall consist of all waveguides of the same model, produced under essentially the same conditions using the same materials and submitted for inspection at one time.
A5.1.2 Group A inspection
Group A inspection shall consist of the inspection items specified in Table A2. Table A2 Group A inspection
Inspection items
Appearance, cross-sectional dimensions, eccentricity, rectangularity or ellipticity and internal stress
A5.1.2.1 Sampling plan
Relevant clauses
1.4, 2.1 and 2.2.4
AQL (number of non-conforming products per hundred units of product) Number of major non-conforming products
Number of minor non-conforming products
Statistical sampling and inspection shall be carried out in accordance with the general inspection level I in GB2828. . Its acceptable quality level (AQL) shall comply with the provisions of Table A2, and major defects and minor defects shall comply with the provisions of GB2828. A5.1.2.2 Rejected batch
If an inspection batch is rejected, the manufacturer may repair the batch of products to correct its defects, or eliminate unqualified products and then submit them for re-inspection. The re-inspection batch shall be inspected with stricter inspection. This re-inspection batch shall be distinguished from the new production batch and clearly marked as a re-inspection batch.
A5.1.3 Group E inspection
Group B inspection shall consist of the inspection items specified in Table A3. Samples shall be taken from the inspection batch that has passed the Group A inspection. Table A3 Group B inspection| |tt||A5.1.3.1 Sampling plan
The sampling plan shall comply with the provisions of special inspection level S-4 in GB2828. Its sample size shall be determined according to the size of the inspection lot from which the sample is drawn during the Group A inspection. Its acceptable quality level (AQL) shall be 6.5 (number of nonconforming products per 100 units of product). A5.1.3.2 Rejected lot
If an inspection lot is rejected, the manufacturer may repair the batch of products to correct its defects, or eliminate nonconforming products and then submit them for re-inspection. The re-inspection lot shall be inspected with stricter inspection. Such re-inspection lot shall be distinguished from the new production lot and clearly marked as a re-inspection lot.
A5.1.3.3 Sample handling
Samples that have passed all the inspection items of Group B can be delivered as finished products. A5.2 Periodic inspection
The periodic inspection shall consist of the inspection items of Group C. A5.2.1 Group C inspection
GB11450.189
The items of Group C inspection are the inspection of the roughness of the inner surface of the waveguide. The Group C inspection shall be carried out on samples that have passed the Group A and Group B inspections.
A5.2.1.1 Sampling plan
The first two sections of the waveguide in the production batch shall be tested. Thereafter, one section shall be selected from every 25 sections for inspection. A5.2.1.2 Failure
In the periodic inspection, if one or more samples do not meet the requirements, the periodic inspection is considered to be unqualified. At this time, the acceptance of the products produced in the period shall be stopped. At the same time, the manufacturer shall find out the reasons and take corrective measures. After taking effective measures, the Group C inspection shall be re-inspected until it is proved that the corrective measures are successful before the acceptance can be resumed. A5.2.1.3 Sample processing
Samples that have undergone Group C inspection shall not be delivered as finished products. B
Waveguide materials and waveguide supply length
(reference)
In order to facilitate production and ordering, this appendix is specially formulated for reference. B1
The brand, chemical composition and supply status of the waveguide materials used to make the waveguide shall comply with the provisions of Table B1. B1
Alloy
Aluminum alloy
H96,H62
LFn,LD
Note: A in the table is the outer width of the waveguide, in millimeters. Chemical composition standard
GB5231
GB5232
GB3190
Finished product supply status
H62 waveguide, supplied after annealing
After tempering:
When A≥80, 0>78.4MPa
When A<80, 0e>117.0MPa
Other materials can also be used according to the requirements of the ordering party, and the relevant requirements shall be agreed upon by the supply and demand parties. Supply length of B2 waveguide
Waveguides can be supplied in standard lengths and special lengths. The standard lengths of waveguides should be 2m, 2.5m, 3m, 3.5m, and 4m. For millimeter waveguides, the supply length should be 1.5m. Waveguide length deviation: For standard length waveguide, it should be 0.5% of the nominal length, for special length waveguide, it should be 0.25% of the length, and positive deviation is always taken.
When ordering standard length waveguide, short pieces can be supplied, but the length of the short pieces should not be less than 60% of the nominal length, and the total weight of the short pieces should not be more than 25% of the order quantity.
Additional remarks:
This standard was drafted by the State-owned Hua Machinery Factory.
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