Video-inspection or Endoscopy
News : The Non Destructive Testing (NDT) are a complex of examinations, tests and surveys that are conducted with the use of methods that do not alter the material and do not require the destruction or removal of samples from the property on checking. They are aimed at the research and identification of structural defects of the structure itself.
The NDT are able to provide information about the shortcomings of a product, its compactness and the results of further processing to the finished product, or to monitor the degradation of structures in service.
The video inspection or endoscopy is a technique of visual inspection at a distance that exploits the use of cameras and optical fibers.
This technique was born in the medical field, but is also used in industry, engineering and construction industries. The inaccessible surfaces can be controlled in view with fiber optic endoscopes ( rigid or flexible), allowing access even into geometrically complex details. These are small cameras which in some cases do not reach the diameter of five millimeters. The use of this technique has numerous advantages: firstly as a method of non-destructive control allows to evaluate the structural characteristics of the material without altering their physical and geometrical status, also it is a system of easy interpretation and allows a substantial saving of time and costs. The video-inspection (or endoscopy ), which offers the chance to get into small cavities, is a widely used, often underestimated, in normal maintenances. Various examples of use related to the above areas are:
• Inspection of: diesel engines or turbines for power generators, gas or fluid pipes, heat exchangers, boilers, pressure tanks, storage tanks, pumps and compressors, adapters, gear boxes, transmissions, etc.
• Inspection of suction pipes, air conditioning, electrical wiring or phone wirings, heating, chimneys, attics, wall voids, drains and manholes, sewers, bridges and viaducts, etc.
As many know, the maintenance of a system is necessary to maintain limited operating costs, to maintain production efficiency and to reduce loss of time related to costly repairs. You can and you should run especially appropriate assessments using visual inspection, to ensure programs of cleaning and effective maintaining , without having to disassemble parts and to waste too much time. So it is possible to obtain an effective maintenance by the use of the video-inspection as a method for the reduction of costs. The important thing is still to have a "hole" of access. The Punto Netto LTD of Griso Gaetano is able to provide the service of video-inspection by the use of endoscopes (should be put on the model and brand) with the possibility of recording and digitization of the images.
Principle of the method:
• the survey is to examine an area that is not accessible by means of other methods of non-destructive testing.
• It is an investigation in view with the aid of special equipment called borescopes and endoscopes, which for their diameters can access the inside of complexes or structural parts. The borescope is composed of a tube of appropriate diameter and length, fitted with a bulb on the end, which is necessary to illuminate the interior of the area to be inspected, and an optical system eye-mirror, to allow viewing of the area. The endoscope, instead, consists of a bundle of optical fibers of suitable diameter and length, required to transmit light, whose remote source, is of an optical system eye-mirror. The borescope is rigid, while the endoscope is flexible, allowing in this way to access in places defiladed than the access hole. So the visualization of the defect is based on the observation of the examined surface as it is or slightly enlarged.
Limits of the method:
• the inspection is possible only on bodies with slits of at least some millimeters which extend along rectilinear or little inflected paths, depending on the type of the probe used.
• The use of probes, implies a partial "invasion" of the object to be examined, making surgery risky: it can cause abrasions or even mechanical failures of materials.
Applications and developments:
• with the advent of the industrial microelectronics the modern endoscopes equipped with cameras (video -scopes) are able to provide detailed images through monitors and color displays.
• they are widely used in medicine, as well as in the craft, civil, mechanical, shipbuilding and industrial fields. Endoscopes are designed for analyzing inaccessible areas, through small openings and lengths that can reach up to a few hundred meters; they provide bright and high resolution images through digital acquisition systems and processing techniques at the forefront.