22.03.2023
Well Control Barriers

Primary well control barrier

During normal drilling operation it will always be the hydrostatic pressure of the drilling fluid that creates the primary barrier to avoid any flow of formation fluid into the well bore. If for any reason the primary barrier is lost the well control equipment together with the drilling fluid in the well bore will be the secondary barrier. This will allow us to re-establish the primary barrier on a safe and efficient way.

Secondary well control barrier

The well control equipment must be able to close and secure the well under all circumstances. Further to that circulation of heavy drilling fluid into the well bore and formation fluid out of the well bore under controlled manner must be possible.

The well control equipment should be able to close on open hole, meaning without tubular, around the bottom hole assembly, BHA for short, and other tubular used in the drilling operation. It should also be able to cut the drill string or lighter tubular and seal the well bore and allow the drill string to be hanged off on the pipe rams or stripped into the well bore.

To avoid single components to create total failure of the system a contingency, i.e. back up function should be built into the system.

All well control equipment must be maintained, function- and pressure tested according to company policy and procedures to assured correct function and integrity when required.

With the well closed in and the drill string in the well bore, formation pressure can be obtained through the drill string by adding shut-in drill pipe pressure, or SIDPP, with pressure hydrostatic.

To secure the drill string and obtain integrity following barriers can be used:

• FOSV, standing for the full opening safety valve,

• One way valves (IBOP, Dart sub),

• Check valves (Drill pipe floats).

To secure the annulus and obtain integrity following barriers can be used:

• Annular Preventer,

• Ram Preventer,

• Shear/Blind Ram,

• Rotating head.

During normal drilling operation two barriers must always be in place where the hydrostatic head of the drilling fluid is one and the BOP’s the other

366 Views 0 Comments Read more
21.03.2023
Functions of Casing

When establishing an oil or gas well, it is not enough just to drill a hole from the surface down to the hydrocarbon layer. The hole must be cased with steel pipes that are duly cemented to the formation in order to make sure than no undesirable event, such as formation fluids entering the hole, and causing blowout take place in the process of drilling. This is one of the key aspects of all drilling programs.

It is very important for anyone engaged in the drilling process to have clear and deep understanding of the casing, what it consists of and how it functions. This is what we have tried to cover below in this mini-article. You are highly encouraged to go through the listing carefully and make sure equal attention is given to each item.

These casings have several important functions of which the following can be named:

• To prevent the hole being washed out in weak formations or collapsing.

• Prevent lost circulation.

• Control the formation pressure, where the density of the drilling fluid (mud) is not heavy enough to control the formation pressure. This can be the case, if one has just drilled through a high pressure zone, set a casing and after that have reduced the mud weight to drill the next type of formation.

• Control the production from the oil / gas bearing formation.

• Prevent water from entering the production zone.

• Make the installation of tubing possible, and production test equipment and other equipment that is necessary to achieve an effective production (seals, pumps etc.).

• Isolate the mud and the hole wall mechanically from each other to prevent fluid loss from the mud to the formation.

• Reduce the friction forces that are present. Especially important with directional drilling.

• Function as a foundation for the BOP and thereby make pressure control possible.

Casing are named after the different tasks they have to perform, here they are named in the order they are inserted:

• Surface casing.

• Intermediate casing.

• Production casing.

• Liner.

Conductor pipe

Conductor is the first casing. It is often a 30’’ pipe placed in a 36’’ hole at a depth of 150 feet to 500 feet under the seabed. With jack up rigs it is often hammered in and is also called a drive pipe.

The purpose of this casing is to ensure the return of the drilling fluid, while at the same time prevent the loose formations on and below the seabed in collapsing into the hole. It is also the foundation of the permanent casing frame when drilling from a floating rig, and is often constructed with extra wall thickness in the top.

Surface casing

Surface casing can be a 20’’ pipe placed in a 26’’ hole at a depth of from 1000 feet to 3000 feet, depending on local conditions. This should line the hole down to a depth where the formations are enough compacted and strong enough to exert the necessary forces, if a BOP is closed in connection with pressure control, as the casing is the foundation for the BOP.

The casing should reach down to a formation that is sufficiently strong to hold the pressure from a drilling fluid, with sufficient density to control the formation pressure down the next casings setting depth. The surface casing should also isolate possible shallow pockets of gas.

Intermediate Casing

Intermediate casing can be 16’’ pipe, but it is often a 13-3/8’’ and a 9-5/8’’ pipe with setting depths down to 11.000 feet or more, but all depending of weights. The more intermediate casings there are, the less the internal diameter of the last set. This will result in a reduced production rate from the well. Intermediate casings are set to isolate weaker formations, so the formation pressures further down can be controlled with an increased drilling fluid density. In addition they must cover the pressure difference between the formation strength and the formation pressure, which are necessary to control a possible kick with a closed BOP.

When drilling directional, drill string can cause serious damage on the casing. A smaller diameter casing can be necessary in a production well, just before a change in direction, as it will be easier to get a thinner pipe through the bent part of the hole. In certain cases, the casing is not going right up the surface, but is hanged off with the help of a casing-hanger, 100 - 300 feet up in the previously set casing. This is because of economic reasons. This casing is called a liner. If the liner afterwards is connected up to the surface, then a connection can be made with a so-called Tie back assembly

Production casing

Production casing is the last set casing. This comes from the reservoir and up to the well head, but in, some cases it is hanged off in the last intermediate casing and is called the production liner.

The production casing should form a sealed connection between the reservoir and the wellhead, and protect the production equipment against pollution from outside, and make it possible to control the well, when the production assembly is retrieved for work over etc. The production casing forms a barrier between reservoir and the production equipment, so the reservoir fluid can be controlled through the perforations and possible gravel or sand packing.

443 Viewing 0 Comments Read more
21.03.2023
DRUG AND ALCOHOL PREVENTION

This training video file was released within the frame of the Ship Operations Cooperative Program, or SOCP for short. As any seafarer will tell you, safety at sea is a sort of illusion. The difficult working conditions in the shipping industry are even worsened by the worldwide epidemic of drug and alcohol abuse. Something abusive at the workplace affects both the seafarer and the ship owner.

The present video addresses the drug and alcohol prevention in the maritime industry. It is intended to provide company-wide drug awareness education to crews, supervisors, and managers. First, the video discusses topics of interest to the widest segment of audience, providing some introduction to the problem, including the causes and effects of the substance abuse, as well as the possible prevention measures.

Then, the information of specific interest to the supervisors and managers is presented, including signs of drug and alcohol abuse, intervention and monitoring, and establishing effective prevention programs. The cargo ships of today are larger and faster than ever before. Safe operation of these massive vessels requires highly skilled crews. While at sea, the crew members may be called at duty at short notice and must have clear mind to perform their duties…

474 Viewing 0 Comments Read more
21.03.2023
ENGLISH COLLOCATIONS IN USE

Here is the second release of the excellent training set for those studying English. It consists of two volumes, namely the self-study and classroom guides for the students of intermediate and advanced levels. You will have to check yourself and understand which one will suit your training needs and capabilities better.

The students of English will be enabled to improve their fluency and, upon completing of all chapters of these books, they will sound much more natural when speaking. The collocations are two or more words that often go together. That is why it makes sense to spend some time studying them, as this knowledge will bring you the capability of richer speaking. The authors of these volumes included the most commonly used and spread combinations for the subject levels.

The books will be equally great when used in the classroom environment and for self-studying. The collocations shall be studied in context, and the trainees shall get confident about what they are studying. Here, the important role is played by the approach used by the releasers of the books, who made a perfect research to understand the real speaking and written English. Needless to say that the set is a great training resource for preparing for the IELTS and/or Cambridge examinations.

599 Views 0 Comments Read more
05.02.2023
SHIP TECHNOLOGY

This publication can be considered an easy reading for the people involved with the maritime industry, and for all others it will be a great introductory volume providing general information on the ship technology. Starting with some background on today’s shipping and shipbuilding industry, the author proceeds with the absolute basics of the naval architecture.

The top important aspects of powering the vessel and ship design have been provided along with the essentials of the ship construction. The safety of the ship and personnel at sea is addressed, as well. Moreover, in addition to the conventional vessels, the author has also covered the navy ships and underwater vehicles. It shall be noted that this is neither a textbook nor an exhaustive reference book on the ship technology.

The idea of the author was rather to provide some very basic introduction so that the readers can follow up, should they get interested in the thing. That is why each section consists not more than a couple of pages giving compact and concise introduction which, however, will be enough to understand if this can be the area of the readers’ interest. The volume closes with an article devoted to the future of shipbuilding.

1045 Views 0 Comments Read more
05.02.2023
DAY SKIPPER FOR SAIL & POWER

Absolutely uncomplicated and really reader-friendly, this title is a great one for those engaged in the RYA Day Skipper course. It shall definitely be treated as the top major reference source since it provides readers with the good insights and updates on the very latest developments and also covers both theoretical part of the course and all necessary practical areas.

The information and explanations provided in the pages of this volume, supplemented with the numerous data diagrams and images, will be of great practical use if you are on your way to obtaining the RYA certificate. Moreover, it is a great training and reference tool for the yachters planning their passages, owing to the amount of the information it gives not only on the navigation and pilotage, but also addressing the boatwork in general.

The safety equipment is paid due attention and dealt with in a separate section, same equally applies to the collision prevention at sea, and other aspects. It will also be good when used to refresh the knowledge of what one has studies some time ago to make sure that the knowledge can be put into practice again. The readers say that this is a must-read one before the course so you are encouraged to go through all its chapters attentively.

594 Viewing 0 Comments Read more
27.12.2022
CARRIAGE OF GOODS BY SEA

The present volume by John Wilson is deservedly considered one of the most definitive guides covering virtually all aspects of this critical area of International Trade Law. The title proved its usefulness and was relied upon by several generations of law students and practicing lawyers.

Remaining the market leading text, the publication is now renowned with the purpose to combine a thorough examination and critical analysis of all law aspects that relate to the maritime transportation of cargo. The volume will be perfect when used as the reference book and training manual for the people starting their deep dive into the UK Shipping Law. It shall be recommended to all people with the interest in the shipping law, particularly in maritime transport.

The sixteen sections of the book provide invaluable insight into such important areas of the maritime shipping as contract of affreightment and implied obligations, time and voyage charter parties, bill of lading, Hamburg, Rotterdam and Hague-Visby Rules together with the application of the latter, freight, limitation of liability etc. Note also that there are more than twenty appendixes to the main text of the book, providing necessary supplementary information, data, documents etc.

1015 Views 0 Comments Read more
27.12.2022
GLOSSARY FOR THE WORLDWIDE TRANSPORTATION OF DANGEROUS GOODS AND HAZARDOUS MATERIALS

The present publication was prepared and released with the ultimate intention to provide all people engaged in the international maritime transportation of the hazardous and dangerous cargoes with the single unit containing the descriptions of all necessary technical terminology.

It is a truly unique and highly usable reference and training resource to be used at all times by the shippers for the quick and correct identification of the materials they carry. This knowledge and understanding is absolutely necessary to make sure that the appropriate safety precautions are in place. The volume has already proven very useful for the professionals representing not only technical, but also commercial parties.

We all know that the terms used today can be quite vague and sometimes even confusing so that the grey areas arise, that may potentially lead to the ambiguities and even dangerous situations on board, with the potential risks to the human lives, safety of the vessel and the environment. In fact, this title is the first one to provide people with the accurate and crystal clear explanations and as such shall be readily available to all transporters and shippers of the subject materials.

1025 Views 0 Comments Read more
« 1 2 ... 5 6 7 8 9 ... 497 498 »
Enter the site
Read Later

    The "Read Later" function allows you to add material to this block with just one click. Just click on the icon and read the articles that interest you at any convenient time.

Top Posts
Rate my site