Are forum members using B31.3 stress allowables for Ti-2 titanium matl in PTA (purified terephtalic acid) manufacturing plants?

regards

I read from an HP article that "Although the ultimate tensile strength (UTS) of SB-265 is 50,000 psi, ASME Code Case 2497-1 allows using a UTS of 58,000 psi, resulting in a thinner tubesheet".

Can any forum member versed in the use of Ti-2 plates share the gist of the above Code Case 2497-1 and how UTS could be raised from 50 ksi to 58 ksi for Ti-2 ?

regards,

sam

I haven't Code case 2497-1 (and I have no reference on it)but I guess the mechanism of changing/ approval "new" titanium properties is something similar with case 2497-2.

It is the work of MTI "Materials Technology Institute", which is not-for-profit technology development organization representing private industry.
You can found some details on internet http://www.mti-global.org/mti/t

"Titanium has always had high initial costs, but even these costs have risen sharply during the past few years.
MC Consulting and MTI recognized that current technology might allow users to reduce the costs without compromising plant safety or reliability. The two organizations suspected strongly that the most commonly used grades of titanium are significantly stronger than the current ASTM Standards indicate.
To confirm this belief, MTI hired Jim McMaster of MC Consulting to evaluate existing data, determine the true strength of these alloys, and present the results to the Materials Properties Council (MPC) and ASME. If these groups agreed, then the allowable stresses for these grades could be increased, and the amount of titanium needed for most applications would be reduced."

To have more details, of course you have to procure Code cases 2497.

best regards.

Thank You, Sir to you, this Intergraph Coade discussion forum & MTI for saving cost.

regards,

sam

Dear sam,

As you can see, MTI not only "suspected strongly" but also were able to demonstrate that "the most commonly used grades of titanium are significantly stronger than the current ASTM Standards indicate"

However, strictly speaking to Ti- Gr2 and B31.3 , ASME B31.3-2010 maintains the value of 50 ksi as minimum Specified Tensile Strength for Titanium Grade 2.

Best regards