Fiber optic inclinometer demonstrates the versatility of FBG sensors

FBG inclinometerFiber optic inclinometer is considered to be one of the most important optical fiber devices used in numerous fields of application. For example, in geophysical engineering, the inclinometer based on the fiber Bragg grating technology (FBG) allows monitoring the angle of inclination at regular intervals along the borehole to profile the land displacement.

Current fiber optic inclinometers utilizing FBG sensors demonstrate a high level of sensitivity and angle of measurement resolution of 0.006°. It should be noted that traditional inclinometers have disadvantages when it comes to their involuntary twist during the process of installation. And optical fiber sensors were widely thought to overcome these limitations due to the absence of moving parts.

Nevertheless, the combination of traditional inclinometers with FBG technology enables us to resolve the challenge and make the fiber optic inclinometers’ operation independent of twisting, therefore, the precision remains constant. Moreover, despite numerous fiber optic techniques that measure temperature, strain, pressure, and other parameters, new fiber optic inclinometer based on a fiber’s taper and a long-period fiber Bragg grating have been recently developed.

The principle of the fiber optic device is based on the use of conventional fiber Mach-Zehnder interferometer that allows dividing the incoming light between two optical fibers and recombining it at a second junction. To be precise, in a Mach-Zehnder system, a long-period fiber Bragg grating dissipates light at its resonant wavelength from the optical fiber core into the cladding, while a second-long period FBG takes light from the cladding back into the fiber core.

The novel fiber optic inclinometer is a simpler device that includes only a single long-period fiber Bragg grating. Moreover, it uses the taper that enables to increase the core field so that part of its light is coupled into the cladding. The fiber optic inclinometer offers the following advantages in its operation:

  • the  immunity  to electromagnetic  interference;
  • the  high sensitivity;  
  • the  compact size;  
  • the multiplexing and remote interrogation abilities.

This optical fiber device based on the interferometer was tested in the measurement of angular displacement. During the experiment, the optical fiber on either side of the taper was sheathed in capillary tubes and then twisted accurately at the taper. Thus, such a bend influences the fringe visibility, but not the location of the fringes.

Optromix is a FBG sensor manufacturer that provides top of the line FBG sensing systems suitable for monitoring of the constructions’ inclination. If you have any questions or would like to buy a FBG product, please contact us at info@optromix.com

The use of fiber optic sensing solutions on active warships

FBGs for active warshipsThe researchers from NASA Armstrong Flight Research Center form a partnership with members of the Naval Surface Warfare Center to create fleet maintenance capabilities with the help of new fiber optic sensing systems. Thus, the development of novel highly promising fiber optic sensing solutions becomes possible.

The thing is that fiber optic technology is considered to be one of the most essential and promising techniques, and the cooperation of the mentioned above organizations may help to find the solution to all current challenges. Herewith, there was a project of Remote Environmental and Condition Monitoring Systems that could be restarted again with the help of new possibilities of optical fiber technology offered by companies.

The main function of fiber optic sensing systems is the record of every parameter. For example, today fiber optic sensors are applied for monitoring temperature, relative humidity, shock, and vibration. Future fiber optic applications include the monitoring of hypergolic propellant fuels, liquid detection, contamination, radiation, strain, and electric and magnetic fields.

Fiber optic sensing solutions allow fulfilling a need to control high valued assets applying fiber optic sensing technology that can be installed with live ordnance. Moreover, the fiber optic sensing system was tested on a self-defense test ship before its installation on real warships.

Such fiber optic technology enables us to increase confidence in real-time fiber optic applications on active warships and ensure sensing systems are ready before future improvements. This optical fiber sensing system contains as many fiber optic sensors as possible to develop a new project that allows demonstrating and detecting main challenges in a relatively short time.

The Office of Naval Research offers fiber optic sensing solutions that are able to monitor, identify, and forecast the health of most critical components, hot spots, fatigue, and damage-prone parts of weapon systems in a reliable and economical way.

Such fiber optic technology may enhance sensing systems while cutting the maintenance cost, current parts life, and new materials. The advantages of fiber optic sensing solutions are based on the application of lightweight, compact fiber optic sensors compared to traditional big, heavy, and hard resisting gages.

Finally, the researchers from NASA developed fiber Bragg Grating or FBG (a fiber optic sensor that reflects certain wavelength and sends all others), as well as two techniques they apply in their fiber optic sensing systems: conventional Wavelength Division Multiplexing and unique FBG Interrogation Technology called the Optical Frequency Domain Reflectometry.

If you want to obtain a highly efficient sensing system, you should choose the Optromix company. Optromix is a manufacturer of innovative fiber optic products for the global market. The company provides the most technologically advanced fiber optic solutions for monitoring worldwide. Optromix is a fast-growing vendor of fiber Bragg grating (FBG) products line such as fiber Bragg grating sensors, FBG interrogators and multiplexers, distributed acoustic sensing (DAS) systems, distributed temperature sensing (DTS) systems. If you are interested in FBG sensors and want to learn more, please contact us at info@optromix.com

FBG pressure sensors for pipeline leakage detection

FBG pressure sensors for leak detectionThe technology of fiber Bragg grating or FBG is widely used in numerous sensing technology fields of application. For example, today FBG pressure sensors are installed to detect the leakage process of prestressed concrete cylinder pipe. This type of pressure sensor is based on the use of a Bourdon tube with two fiber Bragg gratings attached on its outside and inside surfaces.

Such a wider sensing application is caused by an increasingly large number of attractive characteristics of FBG sensors that include intrinsic safety, immunity to electromagnetic fields, remote sensing, and large multiplexing capabilities. Therefore, the pressure parameter remains the most important physical factor in the process industry.

Nevertheless, conventional pressure sensors based on electrical train gauge, vibration wire, mechanics have several disadvantages that include the absence of the ability to withstand harsh environmental conditions with critical electromagnetic interference, adventurous chemicals, or explosion matters. Moreover, such sensing systems do not allow making pressure’s multipoint measurement and online monitoring at a long distance.

It should be noted that the intrinsic pressure sensitivity of an FBG sensor is considered to be about 3.04 pm/MPa, which is quite a low index for the practical pressure measurement. Despite numerous ways proposed to increase the sensitivity factor of FBG pressure sensors, such as the installation of FBG in polymer, soldering metal-coated FBGs on a free elastic cylinder, and embedding the FBG fiber to a diaphragm, all these techniques propose relatively complex structures which are difficult to produce.

The thing is that the prestressed concrete cylinder pipe is widely used for water transportation in different areas, for example, municipal, industrial, and plant piping systems. Thus, the role of FBG pressure sensors for security monitoring and reliability management of huge cylinder pipes remains very important because now the sensing technology still faces numerous challenges.

Nevertheless, the use of a Bourdon tube in FBG pressure sensors as the spring element allows detecting spring elements. Herewith, the measurement sensitivity increases and becomes 1.414 pm/kPa in a range from 0 to 1 MPa while the correlative coefficient is 99.949%. That is the reason why the development of a totally new pressure sensor is planned, which probably finds new FBG sensing applications of pressure quasi-distributed measurement or online monitoring in industry and manufacture fields.

If you want to obtain a highly efficient sensing system, you should choose the Optromix company. Optromix is a manufacturer of innovative fiber optic products for the global market. The company provides the most technologically advanced fiber optic solutions for monitoring worldwide. Optromix is a fast-growing vendor of fiber Bragg grating (FBG) products line such as fiber Bragg grating sensors, FBG interrogators and multiplexers, distributed acoustic sensing (DAS) systems, distributed temperature sensing (DTS) systems. If you are interested in FBG sensors and want to learn more, please contact us at info@optromix.com

Distributed temperature sensing of fiber optics under harsh conditions

DTS in harsh conditionsAccording to a recent study, the technology of distributed temperature sensing allows demonstrating the mechanical properties of fiber optics under harsh conditions. The fact is that numerous land and undersea oil procedures depend heavily on distributed temperature sensing for providing safety and functionality in severe environments.

Usually, the manufacturers use silica-based fiber optics for distributed temperature sensing and distributed acoustic sensing, where temperature and acoustic signals are transmitted and recorded continuously along the length of fiber sensor cable. Such fiber optic solution for FBG interrogator of 15 km length enables well and pipeline operators to apply fiber-based distributed sensing technology to measure the whole wellbore or pipeline span with a resolution of 1 m or less virtually in real-time.

For example, the technology of distributed temperature sensing with fiber optics is used in the operation of steam-assisted gravity drainage or SAGD technique, in which the main goal is the production of heavy crude oil and bitumen materials. Nevertheless, it is only one example, while distributed temperature sensing has numerous fiber optic applications.

It should be noted that the distributed temperature sensing system monitors the following extreme environments while optical fiber operation: high temperatures and pressures, ionizing radiation, and aggressive chemicals in the environment. However, in order to be applied in such severe conditions, fiber optics have to be highly reliable, while transmitting optical power with a minimum of added signal loss.

Most of the fiber sensor cables used in fiber optic applications contain a silica-based core and cladding because of the silica benefits that include high optical fiber transmission, superior thermal stability, and mechanical reliability. Herewith, the use of a polymer coating in fiber cables provides the mechanical protection of fiber optics and minimization of bend-induced optical attenuation.

The technology of distributed temperature sensing also enables to detect the factors limiting the performance of fiber optic cables at elevated temperatures and/or in aggressive conditions. The most frequent failures for fiber optics are related to added attenuation or loss of mechanical strength. Herewith, failure criteria differ from each other and depend on the type of fiber optic application.

If you want to obtain a highly efficient distributed temperature sensing system, you should choose the Optromix company. Optromix is a manufacturer of innovative fiber optic products for the global market. The company provides the most technologically advanced fiber optic solutions for monitoring worldwide. Optromix is a fast-growing vendor of fiber Bragg grating (FBG) products line such as fiber Bragg grating sensors, FBG interrogators and multiplexers, distributed acoustic sensing (DAS) systems, distributed temperature sensing (DTS) systems. If you are interested in DTS systems and want to learn more, please contact us at info@optromix.com