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 AnnaAP

link 10.04.2014 19:17 
Subject: Строительная тематика gen.
Ребят, сил нет уже(((
Для меня это очень незнакомая тематика. Если есть возможность, буду блогодарна за помощь.
Оригинал: Металл проката, используемого для несущих стальных конструкций 2 группы должен удовлетворять требованиям таблицы В.3 приложения В СП 16.13330.2011. По нормируемым показателям ударной вязкости проката КСV-20=34 Дж/см2 (ударная вязкость образцов с V-образным надрезом по ГОСТ 9454-78).

 tumanov

link 10.04.2014 19:33 
V-образным надрезом

V notch

http://www.enkaymachine.com/impacttester.htm

Digital Impact Testing Machine

Technical Specifications:
Maximum capacity : 300J for Charpy Test, 170J for Izod Test
Minimum Scale Graduation : 0.5 J
Pendulum drop angle for Charpy : 140°
Pendulum drop angle for Izop : 90°
Pendulum Weight : 22 Kg
Striking Velocity : Charpy-5.3 m/s, Izod-3.9m/s
Distance of Pendulum centre to specimen Centre : -815 mm
Accuracy : + 0.5 J
DRO for energy absorbed by Specimen
Printer Facility – To print the energy of specimen after test
Selection switch for charpy or Izod Test
Accuracy as per IS & BS Standards
Accessories & Spares:

Charpy/Izod Caliper Gauge
Self Centering Tong
Izod Charpy Sq. Template
Depth Notch Gauge
`U’ Notch Width Gauge
`V’ Notch Angle Gauge
`U’ Notch Milling cutter
`V’ Notch Milling Cutter

 tumanov

link 10.04.2014 19:37 
What is Charpy Testing?
Frequently Asked Questions
Charpy impact testing involves striking a standard notched specimen with a controlled weight pendulum swung from a set height. The standard Charpy-V notch specimen is 55mm long, 10mm square and has a 2mm deep notch with a tip radius of 0.25mm machined on one face. The specimen is supported at its two ends on an anvil and struck on the opposite face to the notch by the pendulum. The amount of energy absorbed in fracturing the test-piece is measured and this gives an indication of the notch toughness of the test material. The pendulum swings through during the test, the height of the swing being a measure of the amount of energy absorbed in fracturing the specimen. Conventionally, three specimens are tested at any one temperature and the results averaged.

Charpy tests show whether a metal can be classified as being either brittle or ductile. This is particularly useful for ferritic steels that show a ductile to brittle transition with decreasing temperature. A brittle metal will absorb a small amount of energy when impact tested, a tough ductile metal absorbs a large amount of energy. The appearance of a fracture surface also gives information about the type of fracture that has occurred; a brittle fracture is bright and crystalline, a ductile fracture is dull and fibrous. The percentage crystallinity is determined by making a judgement of the amount of crystalline or brittle fracture on the surface of the broken specimen, and is a measure of the amount of brittle fracture.

Lateral expansion is a measure of the ductility of the specimen. When a ductile metal is broken, the test-piece deforms before breaking, and material is squeezed out on the sides of the compression face. The amount by which the specimen deforms in this way is measured and expressed as millimetres of lateral expansion.

When reporting the results of a Charpy test, the absorbed energy (in J) is always reported, while the percentage crystallinity and lateral expansion are optional on the test report. It should be emphasised that Charpy tests are qualitative, the results can only be compared with each other or with a requirement in a specification - they cannot be used to calculate the fracture toughness of a weld or parent metal.

http://www.twi-global.com/EasysiteWeb/getresource.axd?AssetID=9122&type=full&servicetype=Inline

 tumanov

link 10.04.2014 19:46 
http://www.worldoftest.com/pdf/metal.pdf

страница 13

также

 Rami88

link 10.04.2014 19:55 
Капитан, вы и правда каким-то добрым стали в последнее время...

AnnaAP, а как вы вообще умудрились взяться за такую жесть, если тематика незнакомая? :0

 Rengo

link 10.04.2014 19:58 
Rolled metal used in category 2 steel bearing structures shall meet the requirements of Table..... . According to the values specified for rolled metal impact strength, KCV-20 =34 J/cm2 (for Charpy V-notch specimen as per GOST...)

 AnnaAP

link 10.04.2014 20:13 
Спасибо!

 AnnaAP

link 10.04.2014 20:14 
Да у меня выбора нет. Это часть общего комплекта

 Wolverine

link 10.04.2014 20:39 
выбор всегда есть.

 AnnaAP

link 10.04.2014 21:19 
Не буду спорить

 

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