This part of well control formula series (part#5) will show you following equations: mud increment for volumetric, lube increment for lubricate and bleed, bottle capacity required for koomey unit, volume of usable fluid, and snubbing force for snubbing operation. Later on, I will show you how to apply equations to particular situation. Anyway this is part 5 and total will be 8 parts.
Mud Increment for Volumetric Method (MI), bbl
![]()
Lube Increment for Lubricate and Bleed Method (LI), bbl
![]()
Bottle Capacity Required, gal

Volume of Usable Fluid, gal

Snubbing force for snubbing operation
Snubbing Force (SF) = Force at wellhead (Fp) + Frictional Force – Buoyed weight of string (Wb)
Basically, you can simply think like this. Total force to overcome pressure at wellbore is a summation of force at wellhead and frictional force minus buoyed weight of string.
Force at wellhead (Fp) can be determined by one of following equations.
![]()
OR
![]()
Note: you can read more detail about force and pressure relationship and its application in the oilfield.
Ref book: Formulas and Calculations for Drilling, Production and Workover, Second Edition
Well Control Books
