Pipeline Monitoring – Locating leakages at oil and gas pipelines

Leaks occurring in underground pipelines constitute a substantial danger for both, human beings and the environment. Oil escaping from pipelines pollutes the earth and ground water.

Leaking gas creates the danger of fires and explosions. In addition, leaks bring about large economic losses. It is extremely important to locate leaks as soon as they occur and to be able to locate small leaks. Until now, monitoring systems have only reacted to large leaks and have not been able to pinpoint them accurately. Oil leaks cause temperature anomalies below the pipeline, whereas escaping gas induces a temperature decrease above the pipeline due to the easing of pressure.

Efficient leak location and the long-term monitoring of gas and oil pipelines can therefore be achieved by measuring the temperatures along a pipeline and observing how these temperatures vary over time. Optical-fibre, temperature-measuring technology presents new opportunities in this connection.

An optical-fibre, temperature-measuring cable is laid along a pipeline, enabling the temperatures in the ground to be measured simultaneously over long pipeline distances with a high degree of locational accuracy.

The sensor cable is completely passive electrically and can therefore by fitted to pipelines where a high risk of explosions exists.

The leakage-location principle by means of optical-fibre, temperature-measuring technology

LIOS Leakage Detection for Oil Pipelines

LIOS Leakage Detection for Gas Pipelines

Using optical-fibre, temperature measuring to monitor pipelines makes possible:

• The economical location of leakages and the long-term monitoring of pipelines

• The monitoring of pipeline sections up to 30 km long by means of a system

• The opportunity of linking individual systems to form an overall system to monitor longer sections if necessary

• The quantifying of leakage rates using model calculations

• It is not necessary to empty and clean the pipeline before inspecting it

• Shutting-down the pipeline is not necessary

• Small quantities of escaping oil can be exactly detected and located

• Damage can be identified in its early stages

The measuring system enables the temperature along a section of pipeline to be measured by using optical-fibre sensors. Temperature anomalies caused by leakages are identified via this system and the efficient location of leakages and long-term monitoring of gas and oil pipelines are thus made possible.

Read more:

• Distributed Temperature Sensing
• LNG and LPG Containment Integrity Monitoring Solutions

Monitoring System for Overhead Line Conductors. Meeting the demands of a changing power environment

Providing sufficient electrical power reliably requires ongoing monitoring of temperatures within overhead transmission lines that are more susceptible to atmospheric changes than buried cables.  Winds, direct sunshine, ambient temperature, rain, ice and snow all affect the temperature of exposed overhead lines and can dramatically impact load limits they are capable of carrying. The fibre optic monitoring system for overhead lines is an inexpensive and highly reliable method that enables real-time monitoring of an entire network or of selected critical spans.

The easy-to-install, low-maintenance system offers a multitude of advantages. By enabling dynamic analysis of network structure, it increases the overall safety and reliability of the grid. It facilitates applying dynamic reactions to transmission requests, resulting in more flexible capacity and revenue management in both the short and long term. And the potential for cost-savings is enormous: downtimes and blackouts can be avoided, and the need for new lines and upgrades (e.g. increasing the height of overhead transmission lines) can be greatly reduced.

Customers dynamically rating the critical spans of their overhead line system can also increase earnings by activating previously unused resources in existing power lines. Dynamic metering of grid capacity and maximized transmission capacity make it possible to respond quickly and dynamically to transmission requests. As new sources of energy are added to the grid, precise load predictions are possible and it is easier to react quickly to overload conditions.

With the help of dynamic network-structure analysis, temperature profile can be monitored over span fields and fittings, depending on the length of the sensor. Load parameters are bundled and transmitted to network control stations online, allowing for real time thermal rating – which means real time supervision of network capacity. This makes it possible to predict load precisely and to avoid wire fatigue caused by repeated high thermal loads. Because decisions based on thermal load often influence upgrading or installation of lines, this translates into better control of grid and wire conditions, as well as optimal sag control and line clearance without requiring new construction activities.

Subsea Tieback – Forum and Exhibition

The annual Subsea Tieback Forum & Exhibition has become the premier event for one of the fastest growing sectors of the oil and gas industry. This year’s Subsea Tieback is scheduled for March 2 – 4, 2010 in Galveston, TX at the Moody Gardens Hotel & Conference Center. Over 2,500 attendees and 150 exhibitors are expected at this year’s conference. You can’t afford to miss it.

In celebration of Subsea Tieback’s 10th year anniversary, this year’s theme is “10 Years And Coming On Strong.” As our industry changes, the sharing of knowledge and collective experiences becomes more and more crucial to improving the quality, safety, and economics of the subsea tieback industry.

The conference board has once again solicited a number of key presentations by industry leaders. As in the past, only by participating in this conference will you be able to receive its benefits, as proceedings will not be published and no Press is ever allowed in the conference area. This is truly a closed forum with open discussion, where the information shared inside the conference room stays inside the conference room.

Read more at forum website:

• Subsea Tieback – Forum & Exhibition

Fiber Optic Distributed Temperature Monitoring for Oil & Gas Production & Reservoir Engineering

How to get more from available resources

Technology is the key driver in the quest for greater efficiency. In the oil and gas industry, there is keen interest and high demand for low-cost, reliable, and easily installable systems to enhance downhole production and recovery.
Trusted partner
Distributed Temperature Sensing Systems have shown great promise for helping the Oil & Gas industry meet the global demand for energy. LIOS Technology GmbH – a trusted partner to the Oil & Gas industry and a leading expert in fiber optic sensing technology – has unleashed the potential for this technology on a number of exciting oil well projects in the Far-East. Along with Integrated Intelligent Smart Well Service Company, the team has successfully developed downhole temperature sensing systems that meet the sector’s unique requirements for performance, cost-effectiveness, and systems feasibility.

Field-proven reliability

Oil reservoirs represent a harsh environment for sensitive electronic components. Equipment deployed downhole must be able to perform 100 % reliably while withstanding heat, pressure, moisture, vibration, and corrosion. Breakdowns can cause unacceptable delays and lost output costing hundreds of thousands of dollars. LIOS Technology offers the most reliable and functional continuous downhole temperature sensing and logging system available for both simple and complex wells. Our modulebased system and open standard protocols enable us to offer you customized solutions for your unique needs.

Features

• Impressive track record – more than 2000 successful fixed installations in more than 80 countries on all continents
• Dependable and field proven system design – no sensitive electronic components or power supply downhole, only the Fiber Optic cable acting as the sensor
• Rugged and durable semiconductor laser diode sensor. Fulfils Telcordia GR-468 quality standard with average product lifetime of 25+ years
• Patented OFDR technology (MM or SM) based on Raman effect delivers temperature readings accurate to within ± 0.06° C (±0.1 F) and 0.5 m (1.5 ft) along the entire sensor length from distances up to 30 km (98425 ft) away
• Market leading calibration features like automated point calibration using 3 rd party temperature source, multi fiber segment calibration and double ended calibration operation mode
• Low-cost third-party optical pressure gauges can be added using the same fiber optic cable for even more detailed measurements
• The multichannel LIOS DTS unit can accommodate up to 8 independent fibers, enabling comprehensive surveillance and Real Time Field Management (RTFM) of multiple wells
• Entirely self-contained DTS unit transmits measurement data via cyber secure, TLS encrypted link to remote SCADA database systems. No on-site PC to power or hack into
• No need to visit well-site to collect data
• Entire DTS system is independently certified for quality by VdS [the German asset insurers association] and many other international certifying bodies

24/7 Data-to-Desk – Easy to install and integrate
Here at LIOS Technology, our goal is to deliver optimal communication solutions to you. We supply your specialists with accurate and real-time information delivered to their desks round-the-clock so that critical decisions can be made immediately. LIOS Technology can easily and economically interface its DTS temperature and pressure measurement system with your system to create a fully Data-to-Desk solution customized to your needs.

An Introduction to Distributed Temperature Sensing

Distributed Temperature Sensing Systems (DTS) are optoelectronic devices which measure temperatures by means of optical fibres functioning as linear sensors. Temperatures are recorded along the optical sensor cable, thus not at points, but as a continuous profile. A high accuracy of temperature determination is achieved over great distances.

Measuring Principle – Raman Effect
Physical measurement dimensions, such as temperature or pressure and tensile forces, can affect glass fibres and locally change the characteristics of light transmission in the fibre. As a result of the attenuation of the light in the quartz glass fibres through scattering, the location of an external physical effect can be determined so that the optical fibre can be employed as a linear sensor.

Optical fibres are made from doped quartz glass. Quartz glass is a form of silicon dioxide (SiO2) with amorphous solid structure. Thermal effects induce lattice oscillations within the solid. When light falls onto these thermally excited molecular oscillations, an interaction occurs between the light particles (photons) and the electrons of the molecule. Light scattering, also known as Raman scattering, occurs in the optical fibre. Unlike incident light, this scattered light undergoes a spectral shift by an amount equivalent to the resonance frequency of the lattice oscillation.

The light scattered back from the fibre optic therefore contains three different spectral shares:

• the Rayleigh scattering with the wavelength of the laser source used,
• the Stokes line components with the higher wavelength in which photons are generated, and
• the Anti-Stokes line components with a lower wavelength than the Rayleigh scattering, in which photons are destroyed.

The intensity of the so-called Anti-Stokes band is temperature-dependent, while the so-called Stokes band is practically independent of temperature. The local temperature of the optical fibre is derived from the ratio of the Anti-Stokes and Stokes light intensities.

Measuring Principle – OFDR Technology
Latest DTS evaluation units deploy the method of Optical Frequency Domain Reflectometry (OFDR) .  The OFDR system provides information on the local characteristic when the backscatter signal detected during the entire measurement time is measured as a function of frequency in a complex fashion, and then subjected to Fourier transformation. The essential benefits of OFDR technology are the quasi continuous wave mode employed by the laser and the narrow-band detection of the optical back scatter signal, whereby a significantly higher signal to noise ratio is achieved than with conventional pulse technology (OTDR). This technical benefit allows the use of affordable semiconductor laser diodes and electronic assemblies for signal averaging.

The optical frequency domain reflectometry has been developed as a high-resolution measurement process for the characterisation of optical wave guides with length dimensions of just a few millimetres. In contrast, its application for the Raman backscatter measurement was introduced and patented by the company LIOS Technology.

Schematic system set up
The temperature measuring system consists of a controller (frequency generator, laser source, optical module, HF mixer, receiver and micro-processor unit) and a quartz glass fibre (fibre optic) as line-shaped temperature sensor.

The design is three-channel, since an additional reference channel is required besides the two measurement channels (Anti-Stokes and Stokes). Corresponding to the OFDR system, the power output of the laser runs through the sinus-shaped frequency starting from a starting frequency in the kilohertz range through the ending frequency in the high megahertz range within a measurement time interval with the help of the High Frequency (HF) modulator. The resulting frequency shift is a direct measurement of the local resolution of the reflectometer. The frequency-modulated laser light is connected to the fibre optic-sensor via the optical module.

The continuously back-scattered Raman light  is spectrally filtered  in the optical module and converted into electrical signals by means of photo detectors. Then the measurement signals are amplified and mixed in the Low Frequency spectral range (LF range). The Fourier transformation of the averaged LF signals results in the two Raman backscatter curves. The amplitudes of these backscatter curves are proportional to the intensity of the Raman scattering of the viewed location. The fibre temperature along the sensor cable results from the amplitude ratio of the two measurement channels.

Head to Wind with DTS – US Renewable Energy Project Equipped with LIOS Condition Monitoring

For one of the biggest American renewable energy companies LIOS provided its well recognized DTS system for monitoring the temperature of two medium voltage power cables directly buried coming from a wind turbine towards the substation. All asset condition monitoring data from the controller is linked in real time by means of Modbus communication protocol to the operator’s SCADA system. The company is convinced by using DTS it has a better control over the thermal cable conditions thus over the load of the power cables which let it utilize its assets more economically. This is a great step for LIOS Technology to strengthen its position in USA for temperature monitoring of power cables at wind farms together with the recently opened office in Morganville, New Jersey.

Read more:

	Smart Grid: Real time ampacity predictions of power cable and aerial line installations
	Distributed temperature monitoring of power cables

Investments in Smartgrid Technologies encourage LIOS to open US office

LIOS Technology, leading provider of state of the art frequency domain based distributed temperature monitoring solutions (DTS), announced today that it has opened an office in Morganville, New Jersey to service the growing demand for distributed temperature solutions in the United States. The New Jersey office expands LIOS’ ability to offer local sales and support services to its fast growing base of customers and prospects in the North-American market.

Corporations in the United States have been strong adopters of DTS solutions particularly in the power industry where the security, reliability and performance of temperature monitoring systems are critical.

“Especially with the SGIG (Smart Grid Investment Grant Program) we are experiencing growth in market demand and level of interest in our products and solutions,” said Konrad Linckh, director of the LIOS New Jersey office. „Our customers are expanding their commitment to ensuring the reliability and performance of the transmission and distribution systems they operate. The continuous and cost-effective grid monitoring solution offered by LIOS supports that commitment and is the essential success factor of Smart Grid implementations.”

The new office is located at:

LIOS Technology Inc.
1400 Campus Drive West
Morganville, NJ 07751, USA

Tel: +1 (732) 970-8062
Fax: +1 (732) 972-4410