IX Международная студенческая научная конференция Студенческий научный форум - 2017

A pipe inspection robot is device that is inserted into pipes to check for obstruction or damage. These robots are traditionally manufactured offshore, are extremely expensive, and are often not adequately supported in the event or malfunction. This had resulted in associated environmental services limited.

Requirements for the robot were that it must operate reliably in confined, dark and wet environments and provides a human wears with a digital video feed of the internal status of the pipes. There robot should as much as possible incorporate off the shaft components, cheap, and potentially onsite repair.

Pipeline systems deteriorate progressively over time. Corrosion accelerates progressively and long term deterioration increases the probability of failure (fatigue cracking). Limiting regular inspecting activities to the "scrap" part of the pipelines only, results ultimately into a pipeline system with questionable integrity. The confidence level in integrity will drop below acceptance levels. Inspection of presently uninspected sections of the pipeline system becomes a must.

Pipelines are proven to be the safest way to transport and distribute Gases and Liquids. Regular inspection is required to maintain that reputation. The larger part of the pipelines system is accessible by In-Line Inspection Tools but this access is limited to the section in between the launching and receiving traps only. Unfortunately, corrosion does not have this limitation. The industry looks for means of inspecting these in-accessible pressure holding piping systems, preferably, without interrupting the operations. It is a fact that sufficiently reliable and accurate inspection results can only be obtained by direct pipe wall contact/access. If that is not feasible from the outside, we have to go inside. Since modifying pipeline systems for In-Line Inspection is mainly not practical, pipe inspection robot pursues development of robotic inspection services for presently in-accessible pipeline systems.

Robotics is one of the fastest growing engineering fields of today. Robots are designed to remove the human factor from labor intensive or dangerous work and also to act in inaccessible environment. The use of robots is more common today than ever before and it is no longer exclusively used by the heavy production industries. The inspection of pipes may be relevant for improving security and efficiency in industrial plants. These specific operations as inspection, maintenance, cleaning etc. are expensive, thus the application of the robots appears to be one of the most attractive solutions. Pipelines which are tools for transporting oils, gases and other fluids such as chemicals, have been employed as major utilities in a number of countries for long time. Recently, many troubles occur in pipelines, and most of them are caused by aging, corrosion, cracks, and mechanical damages from the third parties. So, continuous activities for inspection, maintenance and repair are strongly demanded.

The robots with a flexible (adaptable) structure may boast adaptability to the environment, especially to the pipe diameter, with enhanced dexterity, maneuverability, capability to operate under hostile conditions. The wheeled robots are the simplest, most energy efficient, and have the best potential for long range. Loading the wheels with springs, robots also offer some advantages in maneuverability with the ability to adapt to in-pipe unevenness, move vertically in pipes, and stay stable without slipping in pipes. These types of robots also have the advantage of easier miniaturization. The key problem in their design and implementation consists in combining the capacity of self-moving with that of self-sustaining and the property of low weight and dimension. A very important design objective is represented by the adaptability of the in-pipe robots to the inner diameters of the pipes. Currently, the applications of robots for the maintenance of the pipeline utilities are considered as one of the most attractive solutions available.

As we are observed that in industry , home , power plant etc. there are several problems occurs inside the pipe like Corrosion , Cracking , Dent Mark , Metal Losses etc. so , we are inspecting the pipe with the help of «pipe inspection robot».

Milestones in the life of a Pipeline and possible flaws:

Steel production - impurities, cavities, segregation etc;

Plate production in steel mill - laminations, blisters, scabs, cracks and other rolling defects such as slivers etc;

Pipe production in pipe mill - out of roundness, roofing, any flaws/cracks related to the welding technique;

Pipeline construction and commissioning - dents, plastic deformation, flaws/cracks related to the girth weld;

Pipeline operations - geometric flaws, metal loss and cracks, pipeline movement;

Pipeline rehab and repair - flaws introduced during a rehab or repair operation.

Damage to the pipe:

• Geometrical defects

• Ovality

• Knob

• Ruck

• Rolling imperfection or angularity

• Edge displacement

• Angle error

Inspection method:

1. Video Inspection

Robots deployed for the video inspection of pipe systems possess a maneuverable head that can be turned 360° and tilted 90°. This means that even video pictures can be shot right below the pipe wall. Separate video recording of on-line video data at the control point allows the operator to monitor, achieve and add comments to the footage. The camera has been specially designed for use in pipe systems and has not only great resolution but also a 10 x optical zoom function as well as automatic and manual focusing and adjustable lighting. Using highly specialized, closed-circuit cameras, we can perform a visual inspection of all pipe systems, from as small as 6 millimeters-or 1/4 inch in diameter up to any size. Cameras are the most reliable and effective way to detect leaks and inspect 2 in pipeline systems.

1. Visual Inspection

Due to the cost of advanced inspection techniques, less expensive forms of Nondestructive evaluation is often desired. Visual inspection is currently one of the most commonly used nondestructive evaluation techniques because it is relatively inexpensive as it requires minimal, if any, use of instruments or equipment, and it can be accomplished without data processing. As mentioned previously, visual inspection can only detect surface defects. However, a large number of structural deficiencies have surface indicators (e.g. corrosion, concrete deterioration). Aside from a limited range of detection, visual inspection does have further drawbacks. It is extremely subjective as it depends on the inspector’s training, visual acuity, and state-of-mind. Also external factors such as light intensity, structure complexity, and structure accessibility play a role in determining the effectiveness of visual inspection.

1. Ultrasonic inspection

Based on an electro-magnetic acoustic transducer (EMAT), a new type of ultrasonic sensor uses physical effects such as the Lorentz force and magnetostriction. It therefore works independently of a coupling medium between the sensors and the pipeline to be inspected, thus providing the ideal crack inspection solution for both liquid and gas pipelines. Provided that no cracks are present, the generated wave propagates in one direction from the EMAT sender to the EMAT receiver which records it as a transmission signal. If, however, there is a crack-like defect between the EMAT sender and the EMAT receiver, one part of the signal is reflected back to the EMAT sender where it is recorded as an echo signal by the second EMAT receiver. This means that two acoustic data channels exist for each pixel, i.e. one echo and one transmission channel.Compared with an MFL measurement, the new EMAT module provides much more information, since not only one value (magnetization level) is recorded at one particular pipeline position but several vectors (e.g. signal frequencies and amplitude, travelling time of the acoustic wave etc). Additional data (e.g. lift-off between the EMAT modules and the pipeline) is stored in separate data channels. This independent storage ensures that echo and transmission data can be evaluated unambiguously in relation to the physical measurement.

1. Infrared method

An infrared of an object, as well as detect motion. Many of these types of sensors only measure infrared radiation, rather than emitting it, and thus are known as passive sensor is an electronic device that emits and/or detects infrared radiation in order to sense some aspect of its surroundings. Infrared sensors can measure the heat infrared (PIR) sensors.

All objects emit some form of thermal radiation, usually in the infrared spectrum. This radiation is invisible to our eyes, but can be detected by an infrared sensor that accepts and interprets it. These piezoelectric materials are integrated into a small circuit board. They are wired in such a way so that when the sensor detects an increase in the heat of a small part of its field of view, it will trigger the motion detector's alarm. It is very common for an infrared sensor to be integrated into motion detectors like those used as part of a residential or commercial security system.

An infrared sensor can be thought of as a camera that briefly remembers how an area's infrared radiation appears. A sudden change in one area of the field of view, especially one that moves, will change the way electricity goes from the pyroelectric materials through the rest of the circuit. This will trigger the motion detector to activate an alarm. If the whole field of view changes temperature, this will not trigger the device. This makes it so that sudden flashes of light and natural changes in temperature do not activate the sensor and cause false alarms.

Advantages

• The pipe inspection robot inspects situation inside the pipe which will be recorded and displayed on the monitor screen, it also facilitates working personnel for effective observation, detection, quick analysis and diagnosis.

• Save comprehensive investment, improve work efficiency, more accurate detection.

• Reduce the frequency of entering into the testing environment.

• Operating cost related to other method is low.

• Cost of manufacturing of this robot is relatively low.

Limitation of pipe inspection robot

• Pipe inspection robots have such limitations as their ability to turn in a T-shaped pipe or move in a plug valve.

• Another drawback of earlier robots is that the friction between the pipe and the cables for communication and power supply makes it difficult to move a long distance. A fiber optic communication system can reduce the friction.

• This robot does not work in water.

• This robot works only in empty pipe.

References:

1. R. S. Khurmi & Prof. J. K. Gupta,Theory of Machine -Prof, 2005.

2. M. P. Groover, Automation production systems, and Computer-Integrated Manufacturing - Prof., Prentice Hall, 2011.

3. J.Tiratsoo, Pipeline Pigging and Integrity Technologycs Handbook, Houston, 2013.

4. E.W. McAllister, Pipeline Rules of Thumb Handbook, Eighth Edition: A Manual of Quick, Accurate Solutions to Everyday Pipeline Engineering Problems, USA, 2014.

5. W. Abdulmajeed,Suha M. Hadi, Maher M. Thib, Gas Pipeline Inspection System Using Mobile Robot and GPS ,Lambert, 2009.

6. R. Mora, P. Hopkins, E. Cote, Pipeline Integrity Management Systems: A Practical Approach, 2016.

7. https://www.puretechltd.com

8. http://www.piacr.tk/Introduction to Pipe Inspection and Cleaning Robot

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