JB/T 5075-1991 Lead intensifying screens for radiography JB/T5075-1991 Standard download decompression password: www.bzxz.net
Some standard content:
Mechanical Industry Standard of the People's Republic of China JB/T5075-1991 Lead intensifying screens for radiography Published on June 11, 1991 Implementation by the Ministry of Machinery and Electronics Industry of the People's Republic of China on July 1, 1992 Mechanical Industry Standard of the People's Republic of China Lead intensifying screens for radiography 1 Subject content and scope of application JB/T 50751991 This standard specifies the specifications, technical requirements, test methods, inspection rules and marking, packaging and storage methods of lead intensifying screens for radiography. This standard applies to lead intensifying screens for radiography. 2 Reference standards GB5191 Packaging, storage and transportation pictorial signs Tin, lead and its alloy foil and zinc 3 Product specifications and codes 3.1 Product specifications Product specifications are divided into 23 types according to the width and length of the lead intensifying screen, see Table 1. Table 1 3.2 Thickness The thickness of the lead foil of the front and rear screens of the lead intensifying screen should meet the requirements of the corresponding radiographic standards. 3.3 Product code It is represented by Pb-×××, where ××× is the thickness of the lead box of the lead intensifying screen in millimeters. For example, Pb-0.03 represents a lead intensifying screen with a thickness of 0.03mm. 4 Technical requirements 4.1 Intensification coefficient The intensification coefficient of the lead intensifying screen shall not be less than 2. 4.2 Surface quality 4.2.1 The surface of the lead intensifying screen shall not have holes and scratches visible to the naked eye. 4.2.2 The surface of the lead intensifying screen shall be smooth, clean and flat, and shall not have oxidation color, wrinkles, oil stains, adhesive peeling and mechanical scratches. 4.3 Dimensions and precision requirements 4.3.1 The width and length of the lead intensifying screen shall have an allowable deviation of -0.5mm. 4.3.2 The thickness tolerance of the lead foil used to make the lead intensifying screen shall comply with the general precision specified in GB5191. Approved by the Ministry of Machinery and Electronics Industry on June 11, 1991 and implemented on July 1, 1992 5 Testing method 5.1 Dimensions JB/T5075-1991 5.1.1 The width and length of the lead intensifying screen can be measured with an ordinary vernier caliper. 5.1.2 The thickness of the lead foil can be measured with a micrometer or a lever micrometer. 5.2 Sensitization coefficient 5.2.1 When the thickness of the lead foil is not more than 0.03mm, use the X-ray with a tube voltage of 150~250kV for measurement; when the thickness of the lead foil is greater than 0.03mm to 0.05mm, use the X-ray with a tube voltage of more than 250kV for measurement; when the thickness of the lead foil is greater than 0.05mm to 0.1mm, use the X-ray or ray with a tube voltage of more than 350kV for measurement. 5.2.2, when testing the sensitivity coefficient, non-sensitization film should be used. The film blackness should be between 1.5 and 3.0. 5.2.3 Example 2515 half-wave self-rectifying X-ray machine. Tube voltage 150kV, focal length 800mm, steel plate thickness 15mm, lead intensifying screen thickness 0.03mm, Tianjin III industrial X-ray film, imaging temperature 20℃, imaging time 4min. The test results are shown in Table 2: Intensification conditions No intensifying screen Lead intensifying screen Light intensity mA·minbZxz.net Draw a curve of the relationship between exposure intensity and blackness when using the lead intensifying screen on single logarithmic paper, and then obtain the exposure intensity corresponding to a blackness of 1.68. Intensification coefficient: The intensification coefficient under this condition can be obtained as 2.73. 5.3 Surface quality Exposure intensity without intensifying screen Light intensity with lead intensifying screen The surface quality of the lead intensifying screen shall be inspected by the naked eye and shall comply with the provisions of Article 4.2. 6 Inspection rules 6.1 Under normal circumstances, the lead intensifying screen shall be inspected by the technical inspection department of the manufacturer according to the items specified in Chapters 4 and 5. 6.2 The lead intensifying screen shall be submitted for inspection according to the batch number of the lead foil used. The inspection items, requirements and quantity shall be in accordance with the provisions of Table 3. Table 3 Inspection items Surface quality Intensification coefficient Inspection requirements Inspection quantity Sampling according to GB5191 Inspection before making the lead box Random sampling according to the chrome frost batch number 7 Quality judgment 7.1 Width and length JB/T 5075—1991 If one of the inspected intensifying screens does not meet the requirements of Article 4.3.1, double the number shall be sampled for re-inspection. If one pair still does not meet the requirements, the batch of lead intensifying screens shall be reclassified. 7.2 Surface quality If one of the inspected lead intensifying screens does not meet the requirements of Article 4.2, double the number shall be sampled for re-inspection. If one pair still does not meet the requirements, the batch of lead intensifying screens shall be reclassified. 7.3 Sensitization coefficient If any pair of the inspected lead intensifying screens does not meet the requirements of Article 4.1, the batch of wrong intensifying screens shall be judged as unqualified. 7.4 The unqualified items of the lead intensifying screens after classification shall be re-inspected in accordance with the provisions of Article 6.2: If one pair does not meet the requirements of the re-inspection, the batch of lead intensifying screens shall be judged as unqualified. 8 Marking, packaging and storage 8.1 Marking 8.1.1 Each lead intensifying screen shall have the following markings: a. Product code: b. Manufacturer name or code: c. Product serial number. At least item c must be able to be imaged on the X-ray film. 8.1.2 The imaging mark shall be printed in the upper left corner of the lead intensifying screen. 8.1.3 The imaging font shall not be larger than 3mm×5mm. 8.1.4 The length of the imaging mark shall not be larger than 50mm. 8.2 Packaging 8.2.1 Each pair of lead intensifying screens should be packed in a paper bag with the backing facing outward and the lead box facing inward, and the front and back screens should be separated by soft and smooth thin paper. 8.2.2 Every 10 pairs of lead intensifying screens should have a relatively strong outer packaging and be accompanied by a certificate of inspection. 8.2.3 A larger number of lead intensifying screens should be packed in corrugated paper boxes or wooden boxes, and moisture-proof measures should be taken inside the boxes. The outside of the box should be marked with moisture-proof and handle with care in accordance with GB191. 8.3 Storage The packaged lead intensifying screens should be stored in a room with a relative humidity not exceeding 75% and without corrosive gases. Additional remarks: This standard was proposed by the National Technical Committee for Standardization of Nondestructive Testing. This standard is under the jurisdiction of the Shanghai Institute of Materials. This standard was drafted by Shanghai Medical Equipment Electrochemical Factory. The main drafter of this standard was Guo Huifen. Tip: This standard content only shows part of the intercepted content of the complete standard. If you need the complete standard, please go to the top to download the complete standard document for free.