Buoyancy factor is the factor that is used to compensate loss of weight due to immersion in drilling fluid and you can find the calculation from here https://www.drillingformulas.com/buoyancy-factor-calculation/.

We have created a simple table to help people determine the buoyancy factor quickly. Let’s take a look at the table. In Figure 1, it shows the main page and you can select the mud weight range from 4.0 ppg to 19.0 ppg.

Figure 1– Main Page BF Table

For instant, we choose 8.0 ppg and the table will show buoyancy from 8.0 – 8.9 ppg (Figure 2)

Figure 2 – Buoyancy Factor for 8 ppg Range

## Understand Pressure Loss (Frictional Pressure) in Drilling System

Frictional pressure is pressure loss acting in the opposite direction of fluid flow and today we will look into each component in pressure therefore you will get clearer picture about the frictional pressure in drilling system.

Let take a look at the simple diagram below.

A mud pump creates power to move drilling fluid from point A to C and the frictional pressure or pressure loss is the amount of pressure required to transfer fluid.

Pump pressure is 2,000 psi at the starting point (“A”) and at the end point (“C”), pressure is 0 psi. This tells you that you need 2,000 psi to overcome the frictional pressure in order to move the fluid from point “A” to point “C”.

“Differential pressure between two points in the system is pressure loss while fluid is moved from one to another point.”

## Margin of Overpull in Drillstring

Margin of overpull is additional tension to be applied when pulling the stuck drill string without breaking the tensile limit of the drill string. This is the difference between maximum allowable tensile load of drill string and hook load.

There are several factors when consider about the margin of over pull as listed below;

• Overall drilling conditions
• Hole drag
• Likelihood of getting stuck

## Drill Collar Weight Calculation To Prevent Drill Pipe Buckling

Drill collar provides weight to the bit for drilling and keep the drill string from buckling. Additionally, drill pipe should not run in compression because it can get seriously damaged therefore we need to know weight of drill collar that is enough to provide weight to the bit.

Drill pipe buckle due to insufficient of drill collar

Drill pipe straight because of sufficient drill collar weight

## How to Select a Scientific Calculator for Oilfield Personnel

Working in the oilfield, you need a scientific calculator to help you solve problems with complex formulas. As you learn from this website, drillingformulas.com, you really need a scientific calculator to help you.

There are different brand companies that design scientific calculators. However, the difference in brand names might not alter the similarity in functions and programming. When you are choosing a small scientific calculator, there are a number of factors that you should consider. These factors include; functionality and efficiency, portability and durability.