Titanium Flange rating

[rjstephens]

Hi All,

I am trying to get info on Ti Grd 12 flanges, I need to check the maxium pressure at temp. I cannot find the material group in ASME B16.5 to check the derating from the tables. Does anyone have info on the subject, or must the press/temp rating be calculated from scratch?

Thanks in advance.

Rob

 

[Cockroach]

Whoa...never knew a guy could get a titanium flange. I bet this would cost a guy the farm, aye?

Kenneth J Hueston, PEng
Principal
Sturni-Hueston Engineering Inc
Edmonton, Alberta Canada

 

[MIEngr]

Ti flanges are made from Gr 1 & 2, but I know nothing about grade 12.

Ti flanges can be found for regular ratings 150#, etc but the temperature range is only up to 500 deg F

Several places in the states can also machine Ti flanges for you and have engr on staff give you the information you desire.

 

[rjstephens]

Hi MIEngr,

Thanks for the reply.
The plant we are building is a Copper Refinery in Loas, the medium is at 244 deg C and 5450kPAg. The medium is a Raffinate off gas, pretty nasty stuff. The grade of Titanium that we are using is an AMSE B31.1 specified material, as it appears too be the only grade able to withstand the pressures at these temperatures under the attack of the medium. The flanges are lap-type with CS backing rings. We have sent off requests for information too a few Ti manufactures in the states and have had no joy. An enquiry to the ASME board reveals that we will have to calculate the flange's pressure/temp ratings from scratch using the B16.5 dimensions.

I was wondering if anyone may have dealt with this situation in the past and has a table already calculated. We have in the mean time extropalated, in comparison with a similar material, and using a ramp factor, the data and will perform more detailed calcs if required.

Oh and thanks to Coachroach for his informative reply, I would like to say more, but here in SA we have a code against bringing a fellow PR Eng into disrepute

 

[ApC2Kp]

Rjstephens,
"The flanges are lap-type with CS backing rings." This tells me that this is a titanium stub end with a loose back up flange of carbon steel. This is a lot less cost than a solid titanium flange. I would consider the carbon steel flange as the pressure limiting component. Pressure rating of the flange joint would for ASME B16.5 CL600 to be 8274 kPa @ 260 deg C for group 1.1 forged A105 steel backup flange.
For external corrosion resistance you might want to consider using 304 SS backup flange and teflon coated gr B7 bolts.