More than 80% of crude oil requirement in India is met through imports. Imported crude oil is delivered to the shore tanks through Single Point Mooring (SPM) system. Generally, SPM systems are installed in the sea where water depth is around 30m and more. Crude oil tankers discharge their cargo through these SPMs and off-shore pipelines to storage tanks located in the shore. Therefore, off-shore crude unloading pipelines are a vital link to in the energy supply chain in India. Management of these off-shore pipelines is a challenging task. This paper discusses a case of mechanical damage to an Indian off-shore pipeline and how the damage is being evaluated to ensure reliability and safety of this vital link to ensure sustained and safe operation of the line. The mechanical damage discussed in this paper is in a 48″ off-shore pipeline at a depth of nearly 30m and 24km away from the shore. Owners believe that the damage was caused due to anchor hit from a ship that was buffeted away from safe anchor zone to no anchor zone during a cyclonic storm. Owner had to face considerable challenge in locating and measuring the extent of damage and evaluating its severity and probable impact on the integrity of the pipeline. Owner had done multiple geometry inspection of the pipeline to measure the length of the damage and restriction introduced in the bore due to local reduction in diameter. Possibility of presence of a crack and its likelihood of growth in the near and distant future is also evaluated. The paper also discusses the possible remedial measures to ensure long term integrity of the pipeline.

Pipeline integrity is essential for reliable pipeline operations, for preventing expensive downtime and failures resulting in leaking or spilling oil / gas content to the environment. Leaks can cost industries millions of dollars in loss of energy, while increasing emissions, creating safety hazards, and lowering the reliability of operations. Valves and piping systems can fail in a number of ways. Pipelines are widely used for transportation of fluids like oil & natural gas over long distances to the power plants, public supplies and various industries due to safety, efficiency and low cost. High pressure pipelines are generally buried below the ground level for safety, economic and environmental purposes. For smooth and safe operation of pipeline, there are some associated facilities underground as well above ground facilities like Valves, IJ, Fittings, Launcher & Receiver known as pipeline system. To maintain the integrity of the pipeline system, these facilities need periodic maintenance for their effective operability up to their design life. Valves are one the critical component of the pipeline system and failure of it may cause serious hazard and reduce the control over the various parameters like flow & pressure in the pipeline. Shutting down to repair the leak means a loss in associated industry’s production leading to revenue loss. Darod - Jafarabad Pipeline (DJPL) is one the Natural Gas Pipeline laid by Gujarat State Petronet Limited (GSPL) to transport natural gas in the coastal region of Saurashtra in Gujarat. DJPL is a 212 KM long pipeline with 10 nos. of SV stations. There was leakage observed from bolted body of Ball Valve installed at Intermediate Pigging Station (IPS) and SV-6 of DJPL and these valves are butt welded and in upstream side which need shutdown of pipeline for maintenance or replacement. Maintenance of valve becomes critical, if there is gas leakage from valve body and the pipeline operation cannot be obstructed due to commitment with downstream customers. In such a situation, Stopple-in is the method to isolate the valve without obstructing / shutting the flow in the pipeline. The valves were in upstream side wherein replacement of valve was done by Stopple-in and Cross plugging method. However, gas leakage was from valve body so that hot work (i.e. pipe cutting) for stopple-in was also a challenge. To arrest the leak from bolted section of valve body, sealant injection methodology was adopted. Before applying this technology on high pressure live pipeline, GSPL insisted to perform the demonstration on prototype arrangement. This prototype was manufactured in the way that it has a manmade leakage point. After sealant injection in the system to arrest the leak, system was kept under high pressure of 55 Bar(g) for 24 hours. During demonstration, system sustained the pressure without any failure at leakage point. After successful demonstration, said methodology applied on leakage valve installed on high pressure line without any shutdown to arrest the leak.

Hydrocarbons are the major source of energy in the world. While the global energy demand continues to rise, the shallow water hydrocarbon reserves currently under production are getting exhausted. This has encouraged all major E&P (Exploration & Production) companies around the world to look towards exploration and development of newer deepwater offshore reserves, hitherto largely left untouched. Furthermore, gas reserves-rich nations are also showing a keen interest in exploring new gas markets to boost their exports and, in the process, provide a solution to the energy scarcity of other parts of the world. The two factors mentioned above — the need for newer energy reserves and the urge to tap new energy markets — coupled with the safety, reliability, and cost-effectiveness of pipelines have contributed to the growing number of deepwater gas pipeline projects being executed around the world. “Deepwater Pipelines” per se is not a new concept. Many deepwater pipelines have already been installed in different parts of the world. However, for the Indian energy sector, this is a relatively new development, with the exception of KG basin deepwater pipelines. The Indian government’s HELP (Hydrocarbon Exploration and Leasing Policy) and proposed trans-national submarine gas pipelines are likely to serve as the harbingers of future deepwater pipeline projects in Indian oil & gas sector. Although the technical and codal requirements for deepwater pipelines are the same as that applicable for any shallow water offshore pipeline, there are a few nuances that must be considered extremely important to successfully implement any deepwater pipeline project. This paper elucidates the deepwater pipeline considerations such as pipeline route selection, flow assurance, line pipe material & wall thickness selection, pipeline installation analysis, seabed intervention techniques, alternative integrity validation (AIV) etc.

This paper discusses the pounding tuned mass damper (PTMD) — a novel device developed in a joint collaboration between OneSubsea, a Schlumberger Company and the University of Houston to absorb and dissipate the undesired vibrations generated due to VIV and FIV in subsea pipeline and jumpers. The PTMD is based on principles of both the tuned mass damper (TMD) and the impact damper. The tuned mass in the PTMD absorbs the kinetic energy of the structure and dissipates the absorbed energy through collisions on viscoelastic material. During development, detailed numerical analysis and experimentation were performed to study the effectiveness of the PTMD on the jumper. In the experiment, a full size M-shaped jumper was tested in both air and shallow water conditions for VIV at NASA’s Natural Buoyancy Laboratory (NBL). The experiment also examined the robustness of PTMD for different frequency VIVs. Experimental results showed that the PTMD effectively reduced the in-plane and out-plane vibration of the jumper up to 90%. The observed reduction in vibration amplitude can reduce fatigue damage to jumpers, thus enabling oil and gas operators to optimize spending on vibration mitigation devices, minimize lost revenues, improve system lifespan and availability, and enhance operational flexibility. Reduction in stress of these pipelines also means improved reliability and reduction in costs associated with inspection, maintenance, and repair of subsea jumpers and pipelines. These long-term financial benefits and ability to be installed on existing and new jumpers (pipelines) makes the PTMD a desired solution for vibration suppression in deep water environments.

With the advent of automated measurement of physical dimensional parameters of steel line-pipes, the industry seems to have scaled newer heights, which were previously never even imagined. The dimensional accuracy of each pipe is very critical in the overall success of a line pipe project. The quality of girth welding of pipes during laying, depends upon the close dimensional tolerances of the pipe ends. Even a slight variation in out-of-roundness or end-chamfered profile could lead to drastic irregularities in the pipe-to-pipe joining process. And the manual measuring of the pipe parameters poses a serious question with regards to their accuracy and reliability, due to the effects of man, measurement method and instruments used. There is also a huge limitation of the sampled area measured not exactly resembling the whole pipe, due to the constraints of time and the manual process involved. This paper describes the rise of Automated Pipe Dimension Measurement System (APDMS), which measures a total of 19 dimensional parameters after real-time geometrical & trigonometrical calculations, using parametric data from 72 measurement laser scanners & sensors. The pipe coordinates are measured by laser triangulation technique principally, at each degree circumferentially and 10 mm apart lengthwise. A pipe that needs at least 45 minutes to measure all dimensional parameters manually, by 2 men and almost 25 instruments & accessories, is measured in 2.5 minutes by APDMS with mind-boggling resolution and accuracy. All this is done with a simple push of a button after one-time entering of pipe size. The fully automated system then does its job efficiently to move the pipe accordingly and scan it. The back-end software calculates the required parameters from the measured raw coordinates, evaluates them against set criteria, viz. upper and lower limits, and generates a plot that shows the variation of a parameter along the length or circumference. A calibration system in incorporated to keep the system compliant with accuracy against calibrated and certified standard samples. Initially, we took more than 2000 trials on the whole range of pipe sizes we manufacture, after the installation of system on shop-floor. After trials and establishment, we have so far measured more than 3000 regular production pipes through this system with remarkable results. Analysis has been carried out continuously to ensure the repeatability and reproducibility of the system is as per industry standards. This new, contactless method aims to minimize dimensional variances for fluent and effortless installation of pipes at application site, by ensuring that the dimensions are well within the defined criteria, at each and every point on the pipe during its manufacturing.

The selection of pipeline materials requires consideration of design, construction, operations, maintenance, threats, hazards, risks, safety and economics. Codes and standards provide mandatory and optional requirements and guidelines for the selection of materials. Experience and industry practice help to develop and implement requirements beyond mandatory and code minima, and to augment the achievement of safety and realization of the value of pipeline assets. Both codes and experience get updated over time. When selecting and using materials for pipeline systems, it becomes important to meet with code essentials, while simultaneously recognizing the recommendations of design engineers, materials specialists, manufacturers, installers and operators. There is a wide gamut of materials that can be considered for pipeline systems. These include metallic and non-metallic materials. While steels are still used as the workhorse material in the industry, several non-metallic materials are gaining prominence. These include thermoset materials, for example, reinforced plastics, and thermoplastic materials, such as high-density polyethylene. In addition to pipe, there have been significant developments in other pipeline component materials, such as for valves, fittings, flanges, gaskets, seals, adhesives, bolts and nuts. Considerable advancements have also taken place in the realm of joining and repair methods, for metallic and non-metallic materials. Many of these materials and methodologies are of a proprietary nature, with limits on how much information is divulged by the manufacturers and producers, and what is subject to information that is shared based on confidentialities. Proprietary materials, especially non-metallic products, and some corrosion resistant alloys, are generally not extensively addressed in codes and standards, especially in comparison with steel-based materials that are of the commodity type. Some internationally recognized specifications and standards address the requirements for the qualification of pipeline components, including pipe, fittings, flanges and valves, based on non-metallic materials. Other internationally recognized standards and specifications address the requirements for apparently commodity type materials and materials that are considered to be generally corrosion resistant and relatively long lasting, however, can be susceptible to failure when subjected to specific threats. This paper provides an overview of the process of selection of pipeline materials addressing the above considerations and gives an outline for the implementation of such a process. It describes ways in which a balanced approach to the use of codes and standards that are necessary for regulatory and mandatory compliance, and the application of the benefits of proprietary materials that are available for commercial purposes can be achieved. Thereby, the optimization of asset life cycle and augmentation of safety and reliability during pipeline operations can be enabled.

Hot tapping [1–3] is the operation which allows attaching new branch connection on piping system and pipelines containing hydrocarbons under operating conditions. This operation is associated with high level of risk and is undertaken with extreme caution. A major source of risk from the point of structural integrity is the low limits on value of test pressure as compared to the Code specified test pressures [4]. The reason is pipes are not designed for external pressure and they may “buckle” under external pressure during testing. The current practice is to use curves which are specifically developed by various operating companies [3] and are not generally available in the public domain. The problem becomes severe for large diameter thin pipes where the safe test pressure becomes quite low. This has potential risk as the pressures could be much lower than the operating pressures. This paper discusses this problem and also details out an analytical method which can be used to obtain higher “Strength test pressure” with respect to ratio of parent pipe diameter and thickness. So that design reliability of the hot tap branch can be increased. Methodology explained in paper gives lot of flexibility to go for higher test pressure. FEA analysis is used to demonstrate these results. Globally acceptable procedures also advocate using FEM analysis to confirm the strength test pressure. Based on that FEA analysis was done and it is established that hot tap design can sustain higher test pressure than operating. In reality Hot Taps have been performed and tested successfully with the test pressures as per our proposed method which in a way validates our theory.

This technical paper presents the approach adopted by Kuwait Oil Company to establish an integrated Crude Oil Export Pipeline simulation model in South & East Kuwait area to achieve increase in overall asset-wide production and to improve future Pipeline & Facilities Design. The simulation used As-Built pipeline data along with field data to achieve the objectives of the study. The study had the following objectives: • Identify additional capacity/ deficiency within the system. • Perform Hydraulic Calculations (Pressure losses, Temperature Changes & Estimation of Pumping requirements from Gathering Centers). • Determination of operating constraints/bottlenecks due to non-availability of any critical pipe segments. • Optimization of Network. Accuracy of the pipeline model was verified by comparing simulation results of the existing pipelines & Manifolds with the operating data to confirm that model results duplicated field measurements. The model developed in this study has the characteristics and the ability to predict the flows and pressures under wide range of conditions — including various operational modes and constraints. The model accurately predicted the capacities and also raised few flags which were solved within short time and subsequently the network was optimized. Hydraulics study revealed that no additional capacity or looping were required. Model was studied for reliability of supply under wide range of conditions subject to potential bottlenecks and constraints which were identified in the study.

Slurry pipelines find a special place in industrial applications which require transportation of solid particles through a pipeline. Flow-ability of these solid particles is achieved by mixing and suspending them in water or other carrier fluids. Slurry pipelines are characterized with cost effectiveness for long distances, reliability, low maintenance, low air & noise pollution. Importantly it is eco-friendly and does not affect the environment. Over the past 5 decades, slurry pipelines have proven its effectiveness in cost saving for long distance transportation, safe handling and high reliability. Since the inception of long slurry pipelines in 1957 in Ohio to transport coal, gradually over the period, new technologies in slurry transportation has made it possible to transport minerals and materials over long distances safely and effectively. Many materials such as coal, iron concentrate, phosphate concentrate, copper concentrate, zinc concentrate, lead concentrate, nickel concentrate and limestone have been transported successfully over long distances. The long distance slurry pipelines have certain disadvantages in terms of high initial capital investment, the carrier fluid availability, and importantly it is feasible in areas wherein rail and road transport is not well developed. Most of the mineral concentrates require a beneficiation step that involves grinding of the ore to a very fine size in order to achieve good recovery. This is a wet process and the size of the product is generally suitable for long-distance pipeline transportation. In particular for coal transportation, the drying cost is add-on cost. These all requirements contribute to the transportation cost and make it uneconomical for short distances. Therefore for slurry pipelines to be economic, the distance of transportation will have to be long. In recent times, polyethylene pipes have proven to be very cost effective to transport copper, iron ore, phosphates and gold concentrates. They have high resistance to slurry abrasion, prolonged wear life, high ductility and toughness properties. Pumps are developed to handle high pressures of up to 250 bars and facilitated pumping of solid concentration of 60 to 65% weight. Some alternate carrier fluids result in higher concentrate carrying capacity. Slurry pipelines have proven its high economy and feasibility to operate over long distances. With many developments underway, slurry pipelines will pave way to decrease the load and dependency on rail and roads.