Industrial Borescope

Borescopes are devices that allow the viewing of otherwise difficult-to-access areas. Even simple optical devices with lenses, mirrors and external light sources allow insights that are otherwise not possible. A modern borescope camera is equipped with a digital camera so that the images of the observed area can also be stored and processed. Because of the various possible applications for the borescope camera, there are devices with very different equipment. In general, however, the borescope camera consists of the display and control unit and the probe at the tip of which the camera is located.

Due to the simple placement of the probe of the borescope camera at the points to be examined and the immediate imaging of the targeted areas, the weak points and defects can be quickly detected both during the current inspection cycle and in the case of damage. As a result, much more targeted repairs can be initiated and preventive measures taken. The borescope camera enables quick analyses of areas that are difficult to access without time-consuming disassembly and component openings.

The operation of the borescope camera is easily mastered even by untrained technicians. Electricians, safety specialists, experts in all industries, mechatronics engineers, precision mechanics, car mechanics use the borescope camera for inspections and troubleshooting.

The borescope camera can also be used for training and further education at technical colleges and universities and in the trade as an excellent tool for demonstration and visualization of technical facts or problems. In industry and plant construction, inspections and quality controls can be carried out much faster, more precisely and more cost-effectively with the borescope camera.

Criteria for the selection of a borescope camera
Before a preselection is made from the huge range of devices, it should first be clarified which minimum requirements the borescope camera must meet. Often the following characteristics can be defined in advance:
- Flexibility of the probe
- Diameter of the camera head
- Angularity of the camera head
- IP protection degree of the camera probe
- Viewing angle, viewing direction, focus and image resolution of the camera
- Memory for images and videos
- Interfaces for data transmission, video output
- Possibility to connect different probes
- Accessories

Rigid, semi-rigid or flexible probes for the borescope camera
The probe of the borescope camera can be either a rigid rod or a flexible cable. At the tip there is the camera and inside there are data, light and, if necessary, control lines. Rigid borescopes are often operated without the possibility to take and process images. However, rigid borescopes are also available with a digital camera and this makes it possible to capture, process and store the images shown.

The borescope camera with a rigid probe can be used well for quick inspection, for example under motor vehicles or of higher situated components or installations. For this purpose, the rigid probes are angled at 90 degrees in the upper area or a movable camera head protrudes from the rigid probe rod. The rod length can be up to 3 meters for telescopic versions. The borescope camera thus enables fast and safe visual inspections in difficult-to-access facilities. If a problem area is detected, the necessary equipment for the repair can be set up exactly there.

Flexible and semi-rigid probes allow the borescope camera to be used to inspect pipes and cavities with restricted access. The flexible probes are available in lengths from 1m up to 120m. Lengths of 10 meters and more are usually rolled up on a kind of cable drum. In order to move the long lengths safely through the examined area, there are additional elements that protect the camera head and facilitate the movement. For the places that are difficult to reach with a flexible probe, an borescope cable holder can be used. This borescope cable holder consists of a stable sheath tube in which the flexible cable is guided and fixed.

Diameter of the camera head of the borescope camera
If the borescope camera has to be inserted into cavities through narrow existing openings for quality control or in the search for error causes, the diameter of the camera head is important. On the one hand, the camera head and probe cable must fit through the opening and on the other hand, the probe must be able to be moved within the cavity to the areas to be examined. The dimensions of the camera head are also important for the bending radius of angled cameras.

Borescope camera with multiple articulation – bendability of the camera head
There are applications where it is completely sufficient to work with the fixed, frontally placed camera. However, side cameras are generally better suited for the interior inspection of pipe walls and similarly shaped components. A probe can also contain two fixed cameras for front and side views. For the monitor it is then possible to switch between the current image of the front and the side camera on the control panel.

For some inspections it is advantageous if the camera head can be angled in different directions independent of the current orientation of the probe rod or probe cable. A distinction is made between the four directions of movement: up, down, right, left. For example, an borescope camera can be equipped with a 2-way or 4-way angulation. This means that the borescope camera can be controlled in two or four directions using a rotary switch, buttons or joystick. This multiple mobility is also called multiple articulation. In addition, the camera head can be rotated up to 360 degrees around the axis of the probe. In each case it is indicated whether the probe of the borescope camera can be controlled in 2 directions or 4 directions and whether it can additionally be rotated around the probe axis. Some manufacturers also indicate the maximum angle of the angulation.

IP degree of protection for the probe of the borescope camera
Since the probes, unlike the monitor, come into contact with moisture, dust and foreign matter more often, the probes are often manufactured with high IP protection degrees. The IP degree of protection is an international classification for the protection of electrical devices by the housing.

The first of the two digits stands for the protection of the electrical components against dust and foreign bodies, the second – for protection against water. The higher the number is, the better the internal components are protected. The IP 67 rating for the probe of the borescope camera, for example, means that the camera probe is completely protected against the penetration of dust and can be immersed in water for up to 30 minutes. The borescope camera can therefore be used with this probe to examine filled but not pressurized pipelines, components and containers.

Viewing direction, angle of view, focus and image resolution of the borescope camera
Depending on the area of application, there are different requirements for the level of detail and sharpness of the images. The following specifications of the camera should be taken into account when selecting a device:

Direction of view of the borescope camera without multiple articulation
The camera placed at the tip of the probe can directly display the area perpendicular to the axis with orientation 0 degrees. With orientations between 0 and 170 degree, the imaged area is inclined to the axis at the specified degree. Instead of specifying the direction of view in degrees, sometimes the term side camera or site view camera is used for the 90 degree. In an borescope camera with multiple articulation the camera tip is movable and the direction of view can be controlled via the control panel.

Viewing angle of the borescope camera
The viewing angle or aperture angle of the camera determines the size of the image section. A high viewing angle of the camera provides a better overview and faster orientation. Relatively small angles of view are particularly suitable for details and spatially very narrow inspections. For example, an borescope camera for inspections can be equipped with an aperture angle of 60, 67, 90, 105, 120, 135 or 150 degrees.

Focus and depth of field of view
Optical devices can produce a particularly sharp image of the captured objects for a certain distance. Objects closer or further away appear less detailed. With focusable devices, the sharpness can be adjusted within certain limits. For inspections in very narrow cavities, a probe with a suitable depth of viewing field should be used. Examples are:
Depth of field of view front camera: 5 mm ... 50 mm, 15 mm ... 100 mm / 10 mm ...infinite / 30 mm ... 60 mm
Depth of field of view side camera: 3 mm ... 50 mm

Image resolution
The image resolution is one of the decisive factors for the detail sharpness of the display, especially for the stored images and videos. For some devices, the resolution of the camera itself is higher than the resolution for the stored images and stored videos.

Storage for images and videos in the borescope camera
In many areas it is useful to save the images or video sequences of an inspection in order to create documentation. Many of the digital borescope cameras today offer the possibility to take pictures and videos and store them on an SD card in the device. These images and videos can be provided with a time and date stamp during the recording for better identification. Common formats for storage are JPEG for pictures and MP4 or ASF for videos. These data can later be transferred to a PC or laptop for further processing if required.

Interfaces for data transfer in the borescope camera
The borescope camera can be connected to a PC via the USB interface on the control unit. In most cases two different modes can be selected, one for the transmission of the stored data and one for the transmission of the current image data. Almost every borescope camera with video recording function also has an interface for direct transmission of the video signal to a separate monitor, e.g. a TV screen. Common video output formats are NTSC and PAL. The videos of the inspection can then be shown directly on an external larger screen instead of on the display of the borescope camera.

Borescope camera with various connectable probes
There are model series to which various flexible probes can be connected. This offers the advantage that only one control unit has to be purchased and that the user is already familiar with the handling and operation when changing the probe. The probes may differ not only in the above mentioned characteristics. For example, there are also differences in the illumination of the inspection point, for example with special UV light.

Accessories for the borescope camera
For many applications there are special accessories available to better reach and depict the areas to be examined. It is essential to ensure that the accessories match the model series used.
The following items are used for easier positioning of the probe cable and for protection of the camera:
- Borescope cable holders
- Guide balls
- Camera Carriage
- Centering Brushes

Screw-on magnetic attachments with hooks can be used with the borescope camera to remove magnetic and non-magnetic parts.
Mirror attachments allow other viewing directions for the probes with a fixed camera.
Receivers for locating the damaged areas can be used to find the position of the damaged area in the hidden channels the exact location of which is unknown (for example, sewers on private property). Once the position has been determined, the excavation has to be carried out only at this point.

Additional software can be purchased for some models of the borescope camera. This special software offers e.g. a measurement function to measure and document the cracks or fractures. The documents created in this way can be saved and forwarded by email.

With the help of an industrial borescope camera, the surfaces of components and cavities are visually inspected. But how to understand, whether there is a defective change on the inspected surfaces or not? There are three possible ways to do this:

1. The user of the industrial borescope camera is also an expert for the surfaces to be inspected. Plant manufacturers, who know their machines very well, often also offer the service of a visual inspection of their machinery and equipment. When purchasing a machine, the customer can also sign a maintenance contract, which includes the temporary inspection by means of an industrial borescope camera.

2. The user of the industrial borescope camera is not an expert for the surfaces to be inspected. In this case, during the commissioning of the equipment, it is important to try to take as many images of critical (possibly critical in future) surfaces and components as possible, in order to compare these images with the further ones, taken during the subsequent operation of the machine. This procedure is, of course, appropriate only when a new machine is installed. Since this is often not the case, the images or videos made with the industrial borescope camera must be stored and sent to an expert for analysis.

3. Modern technology also helps a lot to give the best answer to the above-mentioned question. The picture and video data, provided by the industrial borescope camera, can be transmitted by means of Wi-Fi, GPS, or via connection of the borescope camera to the operational data systems or to a PLS present in many plants, in real time. The pictures and videos can then be analyzed by the experts very quickly and the operator of the industrial borescope camera can directly get some valuable advice concerning the further procedure. This is a so-called "remote" version. This approach allows the company to use the less qualified personnel for the actual work on site on the respective machine, since the analysis is done by an expert team locally.

Of course, an industrial borescope camera can also be permanently installed so that even a critical, hidden location could be continuously monitored. For this, just one more remote connection is required and then the personnel on site is no longer necessary.

In general, the analysis of the images and videos, taken by means of a borescope camera, is at the end of the process. The most important point to consider is the creation of clear and meaningful images. This is why, it is recommended to observe the following points, when selecting a borescope camera:

- Resolution of the industrial borescope camera
- Illumination
- Video function
- Size of the memory

Depending on the task to be performed by the user, there may be lower or higher borescope requirements.

Application of a borescope to inspect the Gears in Wind Turbines
The use of the wind power already plays an important role in the transition from fossil to renewable energies. According to the Global Wind Energy Council (GWEC), the wind turbines with an output of 837,451 megawatts were installed worldwide as of December 31, 2021. With the growth of 93.6 gigawatts, 2021 was the second best year so far for the expansion of the wind energy globally.

In order to be able to reliably supply the energy, the complex wind turbines must be installed and operated safely and run largely trouble-free. That is why the important components are regularly checked and serviced. In addition, the large wind turbines are remotely monitored around the clock so that faults and irregularities can be dealt with quickly. This service is provided either by the service department of the turbine manufacturer or by specialized service providers for wind turbines.

Surveys by the German Wind Energy Association (BWE) show that the rotor, gearbox and generator assemblies are less frequently affected by faults than electrical, hydraulic and electronic components. However, longer downtimes and greater effort are often required for troubleshooting the faults in the mechanical components. Therefore, these components should always be checked thoroughly during regular on-site maintenance and the results noted in the maintenance logs. The use of a borescope is ideal for inspecting the hard-to-reach areas of the mechanical components.

The gearboxes of the wind turbines are usually equipped with maintenance openings through which the camera tube of the borescope can be inserted. This means that visual inspections can also be carried out for the internal components without removing protective covers. Particular attention is paid to the highly stressed bearings and gears of the transmission during the checks. Malposition, fractures, flaking, cracks and deposits that have arisen are usually easy to recognize on the images from the borescope camera.

By using the borescope camera when inspecting wind turbines, it is possible to check the condition of important mechanical components via existing component openings. The images of the borescope can be evaluated immediately on site or transferred to a mobile device and forwarded. If necessary, countermeasures such as cleaning or component replacement can be carried out or initiated immediately. Early intervention often avoids major damage, which can lead to longer downtimes and loss of effectiveness of the system.

With the help of the digital images of the borescope, the condition of the examined systems can also be easily documented. By evaluating the type and frequency of the problems encountered, the service provider can constantly improve the preventive maintenance and the availability of the spare parts.

Borescope Cameras for Engine and Machine Inspection
An industrial borescope is an optical device consisting of a tube (rigid or flexible) with an eyepiece on one end and the lens on the other end, connected by the optical system. A borescope camera has a very high image quality and is affordable at a good price. It consists of the visual and lighting systems. The visual system is usually a gradient, rod or lens optics, which is enclosed in the inner metal tube. The lighting system consists of an optical fiber for illuminating the inside of the area. The optical fiber is located between outer and inner metal tubes. The image of the illuminated object is transmitted through the optical system so the viewer’s eye could see it.

A borescope can be equipped with a video camera to transmit the images on a display or computer. They are characterized by four main parameters: the diameter of the operating part, the length of the operating part, the angle of the observation direction and the angle of view. You should take into consideration that increasing of the field of view leads to reducing detalization. It means that you can see a lot but in small sizes or a little but in big sizes and in detail. The main advantage of an engine borescope or industrial borescope camera is a high resolution of up to 25 lines per millimeter.

The borescope is designed to control the work where the inspection area is not easy to reach. They are usually used for visual inspection of aircraft engines, industrial gas turbines, steam turbines, internal combustion engines and the engines of cars and trucks during maintenance and performance evaluation. A borescope camera is common in forensic examinations in law enforcement, in the building inspection to check the ceilings and walls of the buildings, in the weapon industry for the inspection of the fire weapon barrel and so on.

Borescopes can be flexible, rigid or video borescopes. A flexible industrial borescope is used to inspect bended tubes and cavities. They transmit images of areas inaccessible to the naked eye. The main features of these devices are convenience, focus, the eyepiece, a bright illumination, which allows you to clearly view dark places. Video borescope differs from the previous type of borescopes by having a miniature camera at the end of the flexible tube. They also have an illumination for capturing images or videos in dark places. Camera and flexible tube in many models can be immersed in the water. Their main features are high quality, clear digital images and videos.

With the help of this instrument you can get and save images and videos for further transmission in a computer. A rigid engine borescope is used to inspect areas or cavities in a straight line. That is why their usage is limited. There are certain objects and places where it is better to use rigid borescopes, for example, cylinders, fuel injectors and so on. They are affordable at a lower cost and provide high quality images. The status check with the help of an industrial borescope can significantly save maintenance costs. In many cases it allows to understand whether it is necessary to disassemble the turbine for further diagnostics.

Borescope in Aircraft Inspection
Visual inspection is one of the main ways to quickly detect and determine obvious faults, problematic spots, leakages and etc. The main thing that makes profound inspections so challenging is that modern equipment, vehicles and constructions are often so complex and consist of so many parts that not all of them are within easy reach and it is impossible to examine them in a non-destructive way.

Safety of the aircrafts is the top-priority issue and the inspection of the aircrafts does not stand approximate conclusions and assumptions. Borescopes are those devices with the help of which the detailed and very accurate check may be carried out without the need to disassemble certain parts of the aircraft. Due to the optical system of the borescope the professional can see the spot under control in detail without being next to it. This is not the only advantage of the application of borescopes in the aircraft inspection; it also helps to significantly save the time and also carry out inspections on a regular basis before any problems occur, which is a good preventive measure.

For the aircraft inspection the rigid endoscopes or borescopes are often applied, these technical devices are robust, and can be operated in a wide temperature range. Quality maintenance inspection is not possible without checking all the parts of the mechanism and it always follows the task of detecting those spots that may cause trouble, even when there is still no obvious sign for that and the operating process runs well. With the help of the borescope it is possible to detect the elements that are very close to their wear-out, to the end of their service life. Due to the variety of borescopes and also probes that may be attached to the device, there are no unreachable or difficult-to-see places in the aircraft and for the engineer it is an easy-to-perform task that takes a short time. Reduction of the standstill time for the aircrafts is also very advantageous, since it helps to make better planning and more efficient organization of the working time.

Service companies which include borescopes in the range of their equipment are able to offer the customers the best quality service possible when it goes bout airplanes inspections or repair. Precise detection of the problematic places and correspondingly quick replacement of them is one the most desirable services the customer want to get. This provides compliance with the quality and safety standards, which is a pledge of sustainable good reputation.

Borescope in Military and Police
Modern borescopes have reached such a high level of technical development that they turned into auxiliary tools in many life spheres, including military and police. Sometimes borescope is a part of a real video system that allows performing complicated tasks connected with observation, inspection, search for numerous objects and scrutinizing.

Due to the flexibility of the device, and very small size of the camera, which in spite of the size, is capable of creating clear images with high resolution, the borescopes are applied even for hidden inspections which are absolutely unnoticeable for the human eye. The authorized representatives of the law enforcement agencies are able to carry out scrupulous examinations of the hidden parts in the rooms, vehicles, constructions.

Borescopes can be applied for investigations and perform the function of the hidden camera, since they may be inserted into the tiniest holes in the ceiling, floor, wall, door. Sometimes they may be perform even strategic purpose, since with their help the representatives of the police or military departments can obtain valuable information and pictures/videos, which may significantly help the investigators. As a result, many criminal plans and activities can be prevented, timely stopped, the law enforcement agents can infiltrate the criminal groups etc. Application of the borescopes is an obvious help, since it is a considerable help to the detectives and brings the process of searching and analysis of the environment to a much higher level. It is not even as much facilitation as the improvement of the working process.

With the help of the borescope, it is even possible to find the hidden equipment from the opponents’ side; thus, they are performing a protective function as well. Modern borescopes can be applied for the profound control of the military equipment and machines, since the defects unseen to the human eye, can be seen on the screen, to which the data from the borescope can be easily transferred for a detailed processing and analysis.

Quite a valuable piece of equipment it turns to be at the customs. For particular checks and control of the luggage, loads and vehicles, borescopes are applied by the customs officers.

Borescopes applied by the police and military organizations significantly improve the performance, since they provide more information, more details and simply attract attention to the things that could remain unnoticed. They help to find what is hidden, to detect the slightest deviations from the norm, inspect, and of course, to provide more safety for the people engaged in these complicated and often dangerous spheres.

This is an important point, in case something does not work. Of course, you cannot simply judge the performance of a company from the outside. After all, you have to ask yourself the question whether in a few years you will still be able to get support for your borescope camera or order spare parts. Call PCE Instruments, talk to one of the technicians or the order acceptance department. Make conclusions about the quality of the consulting and trust in the worldwide company network of PCE Instruments (since 1999). If you are not sure whether the borescope camera you have selected or suggested by our technicians meets your requirements, you can test the device for two weeks. The defect-free device can be returned without giving reasons if it does not meet your expectations.

For PCE Instruments the customer support is an important service even after the purchase. The user of the device tells us which problems can occur and where the improvements in the borescope camera can be made. Basically, you as a customer can always call the technical consulting hotline of PCE Instruments, both before and after the purchase. The colleagues will ask you specific questions and suggest suitable solutions.

What should you do as a customer if your borescope camera has a defect?
Send the device with a short description of the fault (download the form here) to the respective local branch of PCE Instruments. Our workshop will record the repair case directly upon arrival of the device. In case of a warranty claim, the borescope camera will be repaired free of charge and returned to you. Wearing parts, such as tubes and manual controls are not covered by the warranty. Should the repair lie outside the warranty period or should it not be covered by the warranty for technical reasons, we will send you a free and non-binding cost estimate within max. 2 working days. Then you can decide whether you accept the cost estimate and wish to have the borescope camera repaired or not.
The service of PCE Instruments repairs a defective borescope camera in average 10 working days.

Non-destructive control and inspection has won its popularity for a reason. No matter how accessible the spot to be checked is or how well it is lighted – nowadays it is possible to carry out inspection very effectively just with the help of the correctly chosen device – endoscope or borescope – without the need to open or damage the object or find the ways to access the hidden spot. Modern borescopes range from simple models to sophisticated devices which provide the most accurate results. Borescope with joystick is an example of such a professional device meant for control of very difficult-to-reach and badly lighted locations.

The joystick borescope is very convenient to operate, since the user decides how quickly and in which direction the probe with the camera should move. Joystick operation allows choosing the smallest steps, due to which even the smallest and least visible, but not least harmful, damages may be detected and carefully inspected.

Due to the joystick part, the borescope provides omnidirectional inspection, since the rotation of the camera head is completely flexible. The process of the inspection can be followed on the display, and depending on the image obtained, more careful study of certain spots can be carried out in real time. The real state of things can be carefully studied both, as an image and as video, on the display, and the user can come back or change the angle with the help of the joystick in case some additional inspection is required.

Certain materials, when exposed to UV light, re-radiate some of the light as visible light. This property is called fluorescence. It is a prerequisite for using UV light for visual inspection. In some applications, the inherent fluorescence of the materials to be examined is used. In other cases, special contrast agents are used to obtain meaningful results. An UV light source in an UV lamp or UV borescope enables rapid non-destructive testing with comparatively little effort.

Not only in forensics, when testing security features in banknotes or when checking cleaning results, the UV light considerably expands the possibilities of visual inspections. For example, UV light can also be used for non-destructive surface inspection of materials and components and for leak detection. With an UV borescope, such inspections can be carried out even in the places that are difficult to access.

Depending on the application, there are different requirements concerning the equipment of the UV borescope. In addition to the general specifications to be considered when selecting an industrial endoscope, the wavelength of the emitted UV light must additionally be considered in the case of the UV borescope. For the industrial applications, UV LEDs with a wavelength of 365 nanometers are often used as the light source. Many proteins, oils and contrast agents are optimally excited at this wavelength. For special investigations, for example on the propagation of combustion gases, other wavelengths are required.

To make open cracks and pores on the surface of components visible, auxiliary materials with known fluorescence behavior are applied. The contrast agent penetrates into the flaws and is not removed without residue during subsequent surface cleaning. Irradiation with UV light of the wavelength matching the contrast agent produces a clearly discernible image of the crack and pore distribution. With the UV borescope, the irregularities can not only be made visible. Pictures of the situation can also be taken and later transferred to the computer. This facilitates evaluation, documentation and comparison with other inspection results.

Surface inspection with fluorescent materials is more sensitive than other dye penetrant inspection methods and can be easily automated. In addition, it is ideally suited for dark areas. Continuous cracks on components and other otherwise hardly noticeable leaks can also be detected well with the UV borescope. If necessary, special UV markers are used for this purpose, whose intense glow under UV light makes even the smallest damaged areas visible.

In a rigid borescope, a rigid endoscope has been extended with a digital camera. This makes it possible to immediately show the images of the endoscope on a display, to store them, to forward them and to evaluate them with the help of software. If you want to use a rigid endoscope camera for quality assurance in the production, you can even automate the visual inspections if necessary.

The rigid borescope can be used primarily where all the points to be inspected are accessible along a straight line. The rigid rod even has some advantages over the flexible systems in such applications. For example, the rigid borescope can be guided quickly and safely to the exact position required, where it can still be rotated or pivoted as needed to inspect the cavity. It usually requires little space, is robust and very easy to operate.

For the particular application of the rigid borescope, not only the features of the camera, but also the technical specifications of the borescope must fit the requirements as well as possible. The important features include:

for the borescope

• the viewing direction of the borescope
• the opening angle of the field of view
• the length of the borescope rod
• the diameter of the borecope rod
• the illumination,

for the digital camera

• size and resolution of the display
• the storage possibilities for images, videos
• the interfaces
• processing software for image evaluation.

A rigid borescope can also be used for inspection directly on the conveyor belt if the components to be inspected are positioned appropriately. It provides a quick view into cavities, regardless of whether they are inserted manually or by robot. Based on the images, a decision can be made immediately as to whether the part is good, needs to be reworked or is unusable.