In Addendum 3 of API 650, the expression for "the maximum design pressure limited by uplift" given in F.4.2 is mathematically equivalent with 5.11.2 condition (1)- i.e 0.6Mw + MPi < MDL /1.5 + MDLR.
You can check easily that in case pressure is expressed in [Pa], coefficients are 4/(π*1.5)=0.8488 in the first part, 4/π=1.2732 in the second part and 0.6*2*4/π=1.5278 in the third part.
Above π is 3.14159..
Because the pressure is considered in kPa, they are multiplied by 10^(-3) so they would be 0.0008488, 0.0012732 and 0.0015278.
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