Flange leakage Calculation acc to Blick method

[DavidL]

Hi,
I wonder if anyone have an old paper for made by Robert G Blick "Bending Moments and Leakage at Flanged Joints"?
I got two formulas presented below but I need the background to get a better understanding similiar as peng presented:

[link Point to another website Only the registered members can access] Checking for leakage
M<G*Ab*Sb/4-p*pi*G²/2*(G/8+b*m)

Checking for gasket crushing:
M<p*pi*G³/16+pi*G²*y*n/2-G*Ab*Sb/4
Ab=Bolt area
Sb=Allowable bolt stress
G=Gasket min diameter
y=Gasket seating stress
m=gasket factor
n=Gasket width
p=design pressure
b=effective gasket width

Regards
D

[tony_black]

I have that article - just give me a day or two to dig it up.

[tony_black]

Find link below for the 3 part series "Bending Moments and Leakage at Flanged Joints"

[link Point to another website Only the registered members can access]

[mbc.engg]

Tony_Black thanks. You are Always ready to support...

[srikanthkumar]

Thanks Tony. Great info.

[DavidL]

Thanks a lot Tony_Black!
Really interesting reading, the formulas seems to be derived from basically two asumptions on page 119 (4 in Tony's pdf) the fG,min=m*p (I can buy this) but the second based on crushing < 2*y why is it two times y which Blick refers to as gasket yield stress?

D

[tony_black]

My instinctive first reaction would be he is considering 'y' as the "yield" strength, and, as is usually the case with metals/steels, the compressive strength is more than the tensile strength, and he figured 2x more, which seems appropriate for gasket metals.

[alp.altinok]

thank you Mr. Black

[Paldex]

hi all
can anyone upload the API674 API Standard , Its required urgent.,

Thnks

[DavidL]

-Thanks again Tony
I agree, your explaination make sense. So basically this formula is most appropiate for RTJ-gaskets and maybe spiral wounded but you shouldn't really use it for soft gaskets like graphite gaskets. Normally I check flange leakage with Kellogg method but sometimes it's hard to suceed because the design pressure is equal to the rated flange pressure so it gives you only 50% of rated design pressure left for external bending moments and axial force. Has anyone compared the results from Blick, Kellogg, ASME concerning flange leakage? Or do you use some other methods for flange leakage calc?

D

[tony_black]

Flange leakage is a very complex subject. Your questions have made me decide to pull together a lot of outside information on the subject. Give me a couple days (hopefully).

And, yes, the Blick equations are not so well suited for elastomer/soft gaskets - especially considering "compression set" (creep if you will).

[tony_black]

Once I got thinking/doing/composing, I should have realized earlier, that an entire book can be written on this subject including such topics as, Kellogg, ASME, WRC, PVRC, API, EN 1591, EN 13445, DIN, PD5500.

But have a look at what I started with and let me know if it interests you.