Grade 6 and grade 8 high tensile steel? 1

[ALEng2]

Hi there, I'm hoping one of you guys will find this a very easy question to answer.

I need to know the yield and tensile strength of a steel, but I can't nail down exactly what steel it is. Its a shackle steel listed in Van Beest's Green Pin range. They list two types of steel, grade 8 high tensile and grade 6 high tensile. There's no more information than that.

I have of course contacted the company, and they have given me the tensile and yield strengths for the grade 8 material as TS=860Mpa and YS=580Mpa. That is OK but I really need the strengths of the grade 6 material, however the company just told me that they "don't know" the properties because its "not in their program". Ive got nothing to go on other than they call it grade 6 and presumably it has lower values than the grade 8.

Hopefully one of you with some experience with steels can make me look stupid here, or give me an educated guess at the properties.

Below is a link to the Green Pin catalog where on page 14 you can see the first note of the grade 6 steel. It also states that the steel is quenched and tempered.

Thanks for your time.

 

[TVP]

Shackles produced to EN 13889 do not require testing of tensile specimens in order to obtain yield strength, ultimate tensile strength, etc. The mechanical properties that are required by the standard are Manufacturing proof force, Breaking force, Fatigue resistance, and Impact force, and are tested on full shackles, except for the Impact test. The composition and heat treating parameters are lightly specified. Here is an excerpt from section 5.4.2 Heat treatment:

Shackles shall be hardened from a temperature above the AC3 point and tempered before being subjected to the manufacturing proof force. The tempering temperature shall be at least 420 °C.
The tempering conditions shall be at least as effective as a temperature of 420 °C maintained for a period of 1 h. Sample shackles shall be tested after they have been reheated to and maintained for 1 h at 420 °C and then cooled to room temperature and shall conform to the requirements of 5.5.

 

[unclesyd]

In addition to the information give above here this site refers to several other specifications. The Federal Spec is on the catalog page while the ASTM spec. is under the Specification tab.

http://www.riggingwarehouse.com/products/RIGHARD01/RIGH

ARD01@@2e22/RIGHARD01@@2e22@@2e04.aspx

http://www.riggingwarehouse.com/customer/petrco/specpage

s/Crosby_G-209A%20Alloy%20Screw%20Pin%20Shackles%20Spe
cs.pdf