World’s Tallest Offshore Facilities as of 2015

by DrillingFormulas.Com on June 29, 2015

When people talk about the tallest man-made structure, most people think about buildings as Burj Khalifa, Tokyo Sky Tree, CN Tower etc. However, offshore structures are far even taller than the tallest building.


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Using Combined Load Chart For Stuck Pipe Situation

by DrillingFormulas.Com on June 20, 2015

When the drill string get stuck, there are several ways to free the string as using Jar (up and/or down), straight pull, working torque down, etc. Pulling stuck pipe with torque in the drill string is one of those technique which often utilize to free the stuck drill string. However, there are some concerns that you should know before doing this because torque in the string will reduce a tensile capacity of tubular. This is very important to read and understand the combined load chart (Torque‐Tension Graph) in order to determine the limitation before pulling the pipe.


For this example, we use 5” DP, S-135, NC50 (4-1/2” IF connection) to be a reference figure.

Pipe information

  • Pipe Size and Weight: 5.000″ 19.50ppf 0.362″ wall IEU
  • Pipe Grade: S-135
  • Range: 2
  • Tool Joint: 6.625″ X 3.250″ NC50
  • Tool Joint 120,000 psi Material Yield Strength
  • Premium class

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Determine Stuck Pipe Depth Based on Real Example

by DrillingFormulas.Com on June 13, 2015

This is the real example of how to determine stuck depth using the stuck depth calculation.

Well Information:

  • TD = 8,900’MD/5,600’ TVD
  • Bit Size = 8.5”
  • Drilling fluid = water based mud (PHPA system)
  • Formation: sand shale sequence
  • BHA: 7” mud motor + 9 stands of 5” HWDP S-135, 4-1/2” IF connection
  • Drillstring: 5” DP S135, 4-1/2” IF connection
  • Neutral weight @ 6,850’MD = 175 Klb

While tripping out of hole to 6,850’MD, observe over pull 40 Klb over pick up weight. Stop tripping out and attempt to go down no issue. Attempt to rotate, pipe is able to rotate at 30K ft-lb. Attempt to circulate, observe restricted flow.

Figure 1 - Stuck While Pulling Out

Figure 1 – Stuck While Pulling Out [click to continue…]


Well planning, design and construction phases are mainly concerned with three objectives:

  1. Well objectives as producing or exploring.
  2. Environmental and Safety Objectives
  3. Total expenditure and budget of the project

The above mentioned objectives do not come with standard specific goals and vary based on the location and environment of operations. The planning team has to correctly identify all the goals and factors that influence the project.


The first step of well planning is Well Proposal or Statement of Requirements and it is mainly concerned with the Exploration and Reservoir Engineering Department. The contents of this document include the specific objectives of the well and are can be classified as Exploration, Appraisal or Development. [click to continue…]


Do you ever want to explain to your friends and family members to understand about oil and gas industry?

You know that it is quite difficult to explain someone who never been working and involving in this industry to fully understand the big picture. You need to share this book to them.

Oil: An Introduction for New Zealanders by Ralph D. Samuelson



Published by the New Zealand Ministry of Economic Development [click to continue…]


A mud gas separator or poor boy degasser or gas buster is one of the most critical well control equipment on drilling rigs. It is used to separate gas kick from drilling mud while circulating kick out of wells or circulating gas while drilling or workover operations. The mud gas separator used on drilling rigs is typically a vertical cylindrical vessel with many baffle plates inside because vertical vessels have small footprints. The drilling mud from the well goes into the mud gas separator and hits baffles. Then gas will be removed due to hitting action. The gas will go up and exist to atmosphere via a vent line at the top of the vessel. The drilling fluid drops after colliding baffles and exists the mud gas separator through the line and return to a mud pit.

Many-factors-are-involved-to-properly-size-mud-gas-separator [click to continue…]


Blow Out Preventer (BOP) Equipment VDO Training

by DrillingFormulas.Com on June 2, 2015

BOP equipment is one the most critical equipment for well control operation. Learning about it via VDO training is a good way to understand this subject because you can see what the equipment look like, how these equipment relates to the operation. This VDO will teach you several topics about the BOP equipment as BOP stack, choke manifold, choke panel, accumulator, etc. Additionally, the full VDO transcript is provided to aid your learning.

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Why is Gas Flared?

by DrillingFormulas.Com on May 30, 2015

In petrochemical facilities and refineries flares are important for safety.  These burn the excess hydrocarbon gases in a safe manner as these can’t be recycled or recovered.  These excess hydrocarbon gases are burnt in the flare systems in a manner that is environmentally-sound.  This is an alternative to releasing this vapor directly into our atmosphere.


When flaring occurs this excess gas is combined with air and or steam and burnt off in the flare system which produces carbon dioxide and water vapor.  This process is similar to the burning of LPG or liquefied petroleum gases.  Some of us use these as fuel for home cooking.

Flair use is minimized as much as possible, but it can occur during a shut down or a start-up of any one of our facilities during the maintenance period or during unplanned operational interruptions such as a power outage. [click to continue…]


Blow Out on The Rig Floor VDO

by DrillingFormulas.Com on May 29, 2015

This short VDO will show you how fast of the kick blowing out to the surface.


We don’t know detail about it why this was happened but we can learn from this incident.


  • Always monitoring the well while drilling
  • Be proactive of well control indicators
  • Frequent well control drills are recommended to perform.
  • Emergency abandon rig drills must be practices often.

What is your opinion about this case?

Please feel free to share with us.


Mud leg provides hydrostatic pressure in order to prevent mud going through the separator into the rig. If the pressure in the mud gas separator exceeds hydrostatic pressure provided by mud leg, gas blowing through situation will be happened. Once blow-through occurs with a mud gas separator, it is very difficult to stop this situation until the mud leg column is re-established.


Figure 1 illustrates mud-blow through. The pressure that will create blow-through can be calculated by determining hydrostatic pressure of mud leg. [click to continue…]