Charpy Impact Test Requirement For The Welding Joint

http://www.azom.com/article.aspx?ArticleID=2763

I guess you will have to look deeper into this here:

https://en.wikipedia.org/wiki/Welding_Procedure_Specification

I'd measure the temperature where and when you test it.

Base material.

If you measure the filler you will get a much higher reading.

Huh? The whole test specimen is chilled to the same temperature.

yes dear i know that the whole specimen would be dipped into the chiller. but i m conscern about the reference temperature as to which temperature the specimen should be tested in this case we are using base meatal Q-345R and for which trhe impect test temperature is given as OC whereas for the filler material 7015 the temperature is shown as -20C so i want to know at which temerature the specimen should be tested.

I honestly didn't read the entire posting title. Sorry I was thinking of a different test altogether.

My apologies.

The requirement for the Charpoy Impact test is in the contract and is, usually, spelled out in the "Referenced Documents."

Assuming your requirement is spelled out and is an ASME Code, Division VIII, section l requirement, there are specific rules in the ASME code for exemption from the ASME test requirement. You need to know the clause(s) to make exemption assessment for the ASME Impact Test Requirement. The test is, normally, reserved for High Pressure Vessels and Level I/ Sub-safe. The test is very expensive and may require a series of tests.

Body centered cubic or Ferritic alloys exhibit a significant transition of behavior when Impact Tested over a RANGE of temperatures. Above transition temperature range, Impact specimens fracture in a "ductile" manner, absorbing relatively large amount of energy.

At lower temperatures, i.e. below the transition temperature range, the impact specimens are found to fracture in a "brittle (cleavage) manner.

Within transition temperature range, the materiel fractures in both ductile and brittle.

In other words, the temperature is relative to the fracture test requirements, type of materiel, composition, metallurgy, etc.

the temperature as shown for the filler material for imact test as OC whereas for the filler material is as -20C so which temperature can be used for the subject test

To what temperature could the finished vessel be exposed? Use that, rather than some generic temperature. In your example I would say -20dC rather than 0dC. (Not that either of these is very stringent.)

the finsehed vessel could exposed at 4dc so what sohuld be the test temperature either the base metal or filler material

There is no useful distinction to be made between the temperatures of the base metal and the filler material. This whole exercise seems to be driven by some dopey bureaucrat who understands neither pressure vessels, steel structures, nor plain language.

Perform 2 tests.

one at 0 and one at -20°C.

Try one at 4°C as well.

This is a simple test.

Then you'll see how the weld performs, the base material performs, and how the assembly at expected operation temperatures will perform.

If you just want to do one test do it at -20°C, worst case, most brittle...

Chilled water is it? or the product fill section of a UHT packaging line? Perhaps some deep ocean apparatus....

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