The present publication was written by the recognized and professional maritime lawyer and is intended to provide a good coverage of the important aspects of the international law that apply to the MIO, sanding for the maritime interception operations carried out on the high seas.

The MIO is a widely-used naval operation and as such is being employed within a full range of the conflicts taking place in the modern maritime shipping industry. The volume is dealing with the important legal aspects related to the boarding/searching of the foreign ships as well as the potential arrest of the people and confiscation of the cargo. The author has also performed the analysis of the regulatory framework in connection with the MIO via the legal regimes and bases.

The document is mainly focusing on the various naval operations being looked at as a sub-discipline of the military operations law and will be of particular professional interest to the policy advisors and practitioners, engaged in the subject field. We would recommend having a copy on the bookshelf so that it can be used as a reference at any time when needed. The content is presented in a very reader-friendly and systematic manner.

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The book was written primarily for the owners of the facilities with the relatively small marine diesel engines installed. Prepared by the professional mechanic and excellent teacher, it will give all necessary guidance you need. All of the information is presented in a clear, understandable, and logical manner. It is simply interesting to read this book. The content is arranged in nine chapters starting with the very basic principles of operation common to most of the diesel engines.

The Sailing World and Ocean Navigator have both top-rated this publication due to its readability and amount of useful info. It is definitely to be kept on board any diesel-powered boat as it is good for any marine engineer to have clear understanding of the engines to provide timely maintenance and repair, whenever required. The areas covered by the author include but are not limited to the selection, installation, technical maintenance and repairs of the marine diesel engines.

According to the author, no maintenance and, of course, repair shall ever be undertaken without the sound knowledge of its construction, main parts, and operating principles, and his twenty-year experience in teaching have eventually been reflected in the pages of this guidebook.

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The seas are commonly subjected to the pollution in different forms. In the text of the relevant UN Convention of 1982 the marine pollution has been defined as the one involving either direct or indirect introduction of pollutants resulting in the negative effects to marine life. The present volume contains the results of the scientific assessment of the pollution and covers the general marine pollution by both organic and inorganic pollutants.

The content was developed on the basis of the valuable contributions provided by the group of the recognized and experienced professionals in the field. Starting with the overview of the general marine pollution in the different ocean zones, the content then proceeds to the black tide issue, and oxygenation of the waters. After that, the causes and subsequent effects of the harmful blooms are dealt with.

Note that there is a separate color plate section providing the supplementary information in a very colorful and easy to understand way due to the illustrations. The volume will provide interested readers with the very latest research of the ocean pollution matters and as such will be useful to those dealing with the subject problem.

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The present information paper was officially released by OCIMF with the ultimate goal to provide necessary information on the heading control on the FPSOs, standing for the floating production, storage and offloading units. It shall be used in with, and supplement, the main documents governing the heading control. The recommendations contained in the document pertain to the safe management of the control operations.

Such operation normally takes place in order to allow for the installation and survey activities, as well as the necessary technical maintenance works. It is a common mistake to underestimate the bollard pull that would be required to safely and effectively maintain the heading, and this can eventually result in the unwanted position loss. In addition, more attention shall be paid to the operational limits.

The analysis of the numerous incidents involving the loss of heading control shows that the crew members are not sufficiently aware of the risks, and these guidelines, when properly applied, will contribute in the increase of the awareness. The content of the publication shall be conveyed to the personnel directly engaged in handling the FPSOs and proper understanding of all provisions shall be ensured.

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Functions of the Drill Collars

Let us shed some light on the important functions of the string of drill collars.

Weight on Bit

As discussed earlier, drill collars provide weight on the bit in order to make the bit gouge into the earth and make hole. The amount of weight required depends on several factors. The well planner considers the kind of formations being drilled, the diameter of the hole, the kind of bit being used to drill, the buoyant effect of the drilling fluid, the tendency of the hole to deviate from a true vertical path, and other variables. The correct amount of weight on the bit helps make for efficient drilling of the hole. The weight of each drill collar depends on the OD and the ID, or bore, of the pipe. The weight or force needed on the bit will significantly differ depending on the diameter of the hole.

The buoyant effect of the drilling fluid in the hole must be taken into consideration when determining WOB. Just as a boat floats Functions of the Drill Collarson water, the drill stem floats in drilling fluid, thereby reducing the amount of weight on the bit. The denser the drilling fluid, the greater the buoyant effect, so more drill collars are needed to provide the same weight on the bit. Drilling crews often use additional collars to offset this buoyancy. To account for the buoyant effect of the drilling fluid, the operator takes the required WOB and divides it by the buoyancy factor of the mud to arrive at the air weight of the drill collars.

The amount of deviation in the wellbore must also be taken into consideration when determining WOB. The more the hole deviates from vertical, the greater is the reduction in effective WOB. So, depending on how much the hole deviates from vertical, the well planner must increase the number of drill collars to provide the required WOB.

Holding the Drill String Straight

In addition to putting weight on the bit to make hole efficiently, drilling crews must also use the weight of the collars to keep the drill string above the collars from bending or buckling. If the drill string is kept in tension, it will not bend or buckle. The drill string is kept in tension by two opposing forces – the weight of the drill collars pulling it from below and the drawworks and drilling line pulling it from the surface.

Under normal condition, the drill pipe string wears more rapidly near the center of each joint. Bending or buckling increases the metal fatigue in the center of the joint – that is, bending increases the stress factors in the pipe’s weakest area. Bending also forces the drill string to rub against the wall of the hole, which abrades the sides of the pipe.

Sometimes the driller uses extra weight on the collars to make sure that the drill string stays straight. When using additional weights to hold the drill string straight, the driller usually uses drill collars having a buoyed weight 10% to 30% greater than the amount needed to just to make hole. Providing this extra weight will help keep the string relatively straight as it is rotated.

Providing a Pendulum Effect

Drill collar weight also provides a pendulum effect to cause the bit a drill a more nearly vertical hole. In straight-hole drilling, the most efficient drilling is that which produces a nearly vertical path to the target. Any deviation from vertical tends to increase the cost of the well. Of course, no hole is absolutely vertical from the surface to completion. Different causes force the hole to deviate from Functions of the Drill Collarsvertical. The job of the drilling crew is to keep the wellbore as vertical as possible.

As stated previously, one phenomenon that assists the driller in straight-hole drilling is the pendulum effect. The pendulum effect is the tendency of the drill stem to hang in a vertical position because of the force of gravity pulling on the drill collars. The heavier the pendulum, the stronger is its tendency to remain vertical and the greater is the force needed to cause the drill stem to deviate from vertical. If the drill stem deviates from a true vertical path, the force of gravity tends to pull it back toward vertical. The bit and drill collars tend to drill on the low side of the hole as they seek a more nearly vertical path.

The length of the pendulum is that section of the drill collar string between the bit and the lowest-point tangent to the side of the hole. The lowest-point tangent to the side of the hole is the point at which the drill collars first touch the sides of the hole or at which the first stabilizer touches the sides of the hole. The drilling crew tries to keep this point as high as practical so that the pendulum will be as long as possible. The longer the pendulum, the greater is the tendency for the drill stem to seek a vertical position. There is a limit, however, on the spacing between the bit and the first stabilizer. If the distance is too great, the drill collars may buckle. Tables are available to assist in selecting the appropriate spacing in relation to hole size, drill collar OD and ID, and the angle of the hole.

The weight, the length, and the stiffness of the pendulum are important in straight-hole drilling. A stiff drill collar assembly has a higher point of tangency than a limber one. To achieve both weight and stiffness, crew use large, heavy collars. Undersized and relatively limber drill collars, with a large clearance between the OD of the collar and the wall of the hole, make it harder to keep the hole vertical. Relatively limber drill collar strings tend to bend or flex near the bit; this bending shortens the pendulum considerably Functions of the Drill Collarsand increases the deviation from vertical.

Stabilizing the Bit

Drilling crews use large, heavy, round drill collars with stabilizers to help stabilize the bit when drilling. They use these collars and stabilizers to create what is called a packed bottomhole assembly, or BHA. This term refers to the fact that round drill collars with stabilizers in the lower part of the drill collar assembly are almost the same OD as the bit. In addition, the stabilizers are no more than 1/8 inch smaller in diameter than the hole. In a packed BHA composed of a bit and round drill collars with three or more stabilizers above it, the crew places the first stabilizer immediately above the bit, followed by a short, large-diameter drill collar and a second stabilizer. The third stabilizer is located farther up in the drill collar string.

The use of a packed bottomhole assembly is sometimes referred to as a gun-barrel approach because when the crew uses this assembly, the bit tends to drill straight ahead in spite of forces trying to prevent it from doing so. In other words, the assembly assures that the new wellbore is being drilled in line with the hole that has already been drilled; it is as straight as the barrel of a gun. Using a packed BHA, or the gun-barrel approach, keeps the bit from wobbling, or walking, on the bottom of the hole. This approach also keeps the pressure on the cutting structure of the bit uniform, thereby forcing the bit to cut evenly through the formation. A bit that is not connected to a packed bottomhole assembly may drill an oversize hole, produce unusual bit wear, and slow the rate of penetration. In general, bits drill faster and last longer when well stabilized.

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The natural gas are there in the rock reservoirs deep below the surface of the Earth and therefore under high pressure. They can exist being dissolved in the water or hydrocarbons, or in the free state. Same is the way they are produced from the geological formations. There are three quantities of the gases, namely their temperature, pressure and temperatures, and three major rules governing their behavior, i.e. Charles’ Law, Boyle’s Law, and Gay-Lussac’s Law.

The liquid natural gas trade chain starts with the exploration and production, treatment and liquefaction process, followed by its transportation, and concluded with the storage at final location and regasification. This compact document provides all information that everyone involved in maritime transportation of the LNG should be aware of in order to perform his or her duties in a safe manner.

To do that, they are definitely in need of having a good knowledge of the nature of gases and their technical characteristics, since the failure to know and understand same will eventually result in the unsafe working practice on board, leading to the dangerous and often even catastrophic consequences to the humans on board, vessel and the environment.

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This IMO publication is dealing with the oil spill responses. Even despite a huge number of guidelines and manuals available today on the subject matter, they mostly cover the arctic and temperate waters. The present publication will be beneficial to the people involved in responding to the oil spills that occur in the tropical areas. The information is intended to be applied when preparing the appropriate response strategies.

The idea is to provide them with the necessary info and instructions on the necessary response measure and what should be avoided in such cases. There is some supplementary information included, for example relevant techniques, fate of the oil spilled, marine habitats etc. all of the principles described in this publications have been worked out on the basis of the real life case studies as well as the results of the experiments reported earlier.

Since each spill features its particular characteristics, the information contained in the book shall be treated as guidance and not strict must-follow instructions, and due and reasonable flexibility shall be maintained at all times. The content covers the initial procedures, response actions, and all materials and equipment used.

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The timely detection of the fires on board ships and activation of the shipboard fire extinguishing systems are deservedly treated as the essential key to the proper and effective fire management as they will eventually help to avoid the loss of the human life as well as the damage from occurring to the vessel and cargo. Both these shall be paid due attention when developing the fire response measures.

The main intention of the authors of the present volume was to contribute to the fire safety of the Ro-Ro vessels through application of the cost-effective solutions and reducing the risks of fires taking place in the cargo spaces, and for discussing the technical proposal for the further development of the relevant regulatory framework including the class rules.

The volume consists of six parts and the first of them is devoted to the identification of the so-called RCOs, standing for the risk control options, and assessment of the most cost-efficient options. The authors follow the methodology of the regular formal safety assessment according to the appropriate IMO guidelines, with the five basic steps involved, namely identification of the hazards, risk analysis and control options, assessment, and the recommendations to be followed when making decisions.

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