Is there a mistake in API 10B-2?

[muzza3001]

Hi All,
I'm just looking at equation 9 in API 10B-2 (see screenshot below).

And to me it seems like they have made a mistake. I think they should have

slurry_density (lb/gal) = [highlight #FCE94F](1 / 0.1337)[/highlight] * slurry_mass (lb/sack) / slurry_volume (ft^3/sack)

instead of the

slurry_density (lb/gal) = [highlight #FCE94F]0.1337[/highlight] * slurry_mass (lb/sack) / slurry_volume (ft^3/sack)

stated. Does anyone else agree?

 

[HTURKAK]

Slurry Density = Slurry Mass/Slurry Volume

And use always consistent units.. ( in this case assume unit wt is density )

If the unit of ρs = pounds per gallon, the unit of Slurry Mass SHALL be in pounds and the Slurry Volume unit SHALL be in gallons..

If the units of Vc , Vw, ∑Vadliq, ∑VadSol in gallons and the unit of Vs is in cu-ft , you shall multiply the sum with 0.1337 to convert to the cu-ft,

Literally , if Vs = Vc + Vw + ∑Vadliq + ∑VadSol and the unit of right hand side quantities in gallons Vs will also be in gallons and you shall multiply with 0.1337 , Vs = 0.1337* ( Vc + Vw + ∑Vadliq + ∑VadSol ) to get in cu- ft.

slurry_density (lb/gal) = 0.1337 * slurry_mass (lb/sack) / 0.1337* slurry_volume ( gallon/sack)

Remember, always complicate the calculations so that the others would think that the engineers perform very sophisticated calculations..

Edit: In general , the structural engineers prefer to multiply some quantities with 0.667 then multiply somewhere else with 3/2 to get the same..

 

[muzza3001]

Thanks. Yeah my bad, I was doing something silly before. Seems ok now! Doh.