HG/T 2438-1993 Quality classification of modified phenolic glass fiber reinforced plastic ball valves HG/T2438-1993 standard download decompression password: www.bzxz.net
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Chemical Industry Standard of the People's Republic of China HG/T2438-93Www.bzxZ.net Modified phenolic glass fiber Quality classification of reinforced plastic ball valves Published on June 14, 1993 Implemented on January 1, 1994 Published by the Ministry of Chemical Industry of the People's Republic of China Chemical Industry Standard of the People's Republic of China Quality classification of modified phenolic glass fiber reinforced plastic ball valves Subject content and scope of application HG/T2438-93 This standard specifies the quality classification of modified phenolic glass fiber reinforced plastic Detailed rules, test methods and inspection regulations for ball valve quality classification. This standard is applicable to modified phenolic glass fiber reinforced plastic low-pressure floating ball valves (hereinafter referred to as ball valves) with medium-alkali glass fiber as reinforcement material, modified phenolic resin as matrix and compression molding. The use range is in accordance with the provisions of ZBQ23002 standard; the applicable specifications are eight types from Dg15 to 100mm. Other specifications of ball valves greater than Dg100mm can refer to 2 Reference standards ZBQ23002 "Modified phenolic glass fiber reinforced plastic ball valve" 3 Product quality classification Ball valve product quality is divided into superior, first-class and qualified products. 4 Product quality classification details 4.1 The raw materials should comply with the relevant provisions of Article 2.2.1 and 2.2.2 of ZBQ23002 standard. 4.2 The structural dimensions and flange connection dimensions of various specifications of ball valves with nominal diameter Dg15--100mm should comply with the relevant provisions of Chapter 1 and Article 2.3.7 of ZBQ23002 standard 4.3 The mechanical properties classification indicators of molding material molded specimens used to manufacture ball valves are shown in Table 1. Table 1 Mechanical properties Tensile strength Compressive strength Bending strength Impact toughness Superior products The classification indicators of visible defects on the surface of ball valve molded parts are shown in Table 2.4.4 Defect name Small pieces falling off or peeling off on the edge surface, threads and bolt holes of the body and other molded parts. There are slight cracks on the surface or under the surface of the molded parts. Approved by the Ministry of Chemical Industry of the People's Republic of China on 1993-06-14. Superior products Peeling length 1 piece/each part No such defects First-class products First-class products Peeling length 1 piece/each part Crack length 3 pieces/each part Qualified products Qualified products Peeling length 1 piece/each part||tt| |Crack length 3 pieces/each part 1994-01-01 implementation Defect name Prying skin pattern HG/T2438-93 Continued cutting 2 Superior product The surface of the molded part is arched, with obvious or unclear boundaries The surface is uneven, slightly similar to the surface of orange peel, Non-metallic impurities mixed in the molded part, Metal impurities mixed in the molded part. The edges and corners of the molded parts are not completely filled No such defect No such defect No such defect No such defect No such defect For the flatness tolerance of the flange sealing surfaces at both ends of the ball valve, see Table 3, 4.5 Superior products 4.6 For the water pressure bursting performance of ball valves, see Table 4. Nominal diameter Above 80mm 15-80mm| |tt||Superior products 4.7 The classification index of effective sealing switching times of ball valves is shown in Table 5. Unit Superior products First-class products First-class products First-class products Bubble diameter 1 piece/each part Diameter <13mm Length <0.8mm 1 piece/each part No such defect No such defect Qualified products First-class products Qualified products 4.8 Other technical conditions not covered by this standard shall comply with the requirements of ZBQ23002 standard. 5 Test methods 5.1 Test methods for mechanical properties of molding materials shall comply with the provisions of Chapter 3 of ZBQ23002 standard. Qualified products Pool diameter 1 piece/each part Diameter <29mm Length <1.5mm 1 piece/each part No such defects| |tt||No such defect Qualified product 5.2 The visible defects of the appearance of each molded part of the Yuemen are inspected with a vernier caliper and visual inspection. 5.3 The flatness tolerance measurement method of the flange sealing surface is as follows: Place the valve body vertically on a metal platform, set a magnetic base dial indicator on the platform, use the dial indicator to measure the rod head along the flange sealing surface for one circle, and measure the absolute difference between the highest point and the lowest point as the flatness tolerance; each end of the flange is tested at least twice at different positions, and the maximum value of the four test values is taken as the test result. 5.4 The test method of water pressure bursting performance is carried out in accordance with Article 3.3.5 of ZBQ23003 standard. 5.5 The test method of effective sealing switching times is as follows: After the valve is filled with water, both ends are closed, and then the ball is turned 90°, and the switch is 5-10 times per minute. After reaching 800 times, a water pressure seal test of 1.5 times the working pressure is carried out, and no leakage is qualified. The test of first-class products should be carried out in two stages: the first stage is the same as the inspection method of qualified products. If qualified, conduct another 200 switch tests, and then conduct a second 1.5 times working pressure water pressure seal test. If there is no leakage, it is a first-class product. The inspection of superior products needs to be carried out in three stages: the first, second, and third stages are the same as the inspection of first-class products. If there is no leakage, conduct another 500 switch tests, and then conduct a third 1.5 times working pressure water pressure seal test. If there is no leakage, it is a superior product. 6 Inspection rules 6.1 Batch and sampling HG/T2438-93 6.1.1 Mechanical properties inspection of molding materials, according to the production batch disc as a batch sample preparation inspection, 6.1.2 The visible defects of the appearance of molded parts and the flatness tolerance of the sealing surface are inspected one by one. 6.1.3 Water pressure bursting performance, sample 5 pieces per batch according to the variety, and the maximum batch disc shall not exceed 2,000 pieces. 6.1.4 Effective seal opening and closing times, 3 pieces are sampled per batch according to the variety, and the maximum batch shall not exceed 2000 pieces. 6.2 Judgment rules 6.2.1 Any repaired parts or products shall not be determined as first-class or superior products. 6.2.2 According to the mechanical properties of the samples, the test values of the visible surface defects of the parts and the flatness tolerance of the sealing surface, the parts shall be pre-classified according to the provisions of Table 1, Table 2 and Table 3. 6.2.3 For ball valve products assembled with parts and components of the same grade after pre-classification, samples shall be drawn according to the sampling provisions of Chapter 6 to test their water pressure bursting performance and effective seal opening and closing times, and the grade of the batch of valves shall be determined according to the provisions of Table 4 and Table 5. If all the samples in the two tests meet or exceed the corresponding index requirements of the pre-classification, the pre-classification level shall be the final grade of the batch of products; otherwise, the grade corresponding to the sample with the lowest test result in the two tests shall be the final grade of the batch of products. Additional Notes: This standard was proposed by China National Chemical Equipment Corporation and is under the jurisdiction of the National Technical Committee for Standardization of Non-metallic Chemical Equipment. This standard was drafted by the Chemical Machinery Research Institute of the Ministry of Chemical Industry. The main drafters of this standard are: Zhang Junke and Chen Guangping. People's Republic of China Chemical Industry Standard Quality Classification Standard for Modified Phenolic Glass Fiber Reinforced Plastic Ball Valves HG/T2438-93 Editor China National Chemical Equipment Corporation Postal Code 100011 Printed by Beijing Institute of Chemical Technology Printing Factory Copyright reserved 880×12301/16 June 1994 Edition No Reprinting Printing Sheet 0.5 7.5 thousand words First Printing in June 1994 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.