The application of paint and varnish coatings on the surface of building structures, equipment and vehicle bodies should be carried out in accordance with clear requirements of operational standards. One of the parameters of quality external processing is the thickness. Although an inexperienced user of the same car can be guided by the law "more is better", in practice this rule does not work for a variety of technical and physical reasons. Professionals, in turn, use special devices to determine this parameter. The common name for the device for measuring the thickness of the paint coating is a thickness gauge, although in its narrowly specialized spheres its modification in the form of a micrometer is used.
General device of thickness gauge
The first devices of this type had large dimensions and weighty equipment, thanks to which the principle of measurement was realized. In modern, including ultrasonic models, there is no need for a massive filling - these are compact devices that are easy to control and take readings. A standard device for measuring the thickness of a paint coating of this type consists of a housing, a sensor, a keypad and a display. That is, the user receives the data electronically. Moreover, in some versions it is possible to instantly send the received information to the computer's database for further processing. As a battery, batteries are most often used, which makes it possible to measure away from the mains. By the way, some modifications support the function of alerting the operator about an imminent discharge.
What is the difference between an ultrasonic thickness gauge?
Practically all modern devices for measuring the thickness of coatings are divided into two groups - magnetic and ultrasonic. The first category also has several subgroups that differ in the principle of work. The ultrasonic device for measuring the thickness of paintwork is considered to be the most progressive tool of this kind, since it allows obtaining more accurate data, and also has a wide range of applications.
Models working on ultrasonic pulses allow to work with both metallic and non-metallic bases, which is a cardinal difference from magnetic and electromagnetic analogues. In this case, the measurement principle is based on the propagation of pulses in the form of longitudinal ultrasonic waves. This means that a paint gauge of this type will read the data by recording a time gap over which the sound signal triggered by the outgoing pulse will be reflected.
Before starting the operation, it is necessary to make sure that the instrument is calibrated and is ready to provide the best accuracy. Then the desired speed of sound is selected. This parameter, together with the speed of sound, will be determined by the type of the target material - again, metallic or non-metallic. For example, the car thickness gage can work with pulses, the speed of which is about 5900 m / s. Before direct measurement, the working area must be treated with a special lubricant agent, which will improve the ability of the sensitive transducer to interact with the surface. Also at the preparation stage it is desirable to maximally clean the surface of various kinds of contaminants and layers. This will determine the correctness of the testimony.
The process of measurement itself consists in the installation of an external sensor-transducer in direct proximity to the target material. Within a few seconds, depending on the modification of the instrument, the characteristics of the surveyed coating will be displayed on the screen. Moreover, even in standard versions, the modern thickness gauge of a paint allows to reflect a complex set of data, among which are the impulse readings, which can make a difference for specialists.
In the long-term use of the user requires the implementation of simple preventive measures. In addition to regular updating of the batteries, it will be necessary to read the case with a check on the condition of the functional elements. Special care is required in handling the sensor adapter. As a rule, it is made of propylene, so any damage can deform its structure. Also, the device for measuring the thickness of the paint coating needs periodic test tests on the samples. The wider the set of material base, from which one can take data on the characteristics of interaction with pulses, the higher the probability of obtaining qualitative measurement results. It is these data that become the basis for the selection of the above range and the speed of propagation of sound waves.
Reviews of models TESTBOY
This is a specialized line of ultrasonic models, designed for use in different areas. In particular, the modification 72 allows to work with all kinds of non-magnetic coatings from lacquers and enamels to copper and zinc sprayings. According to users of the TESTBOY family, the models are characterized by a high degree of accuracy, ergonomic handling and mechanical stability. Particularly praise is the car's thickness gage, because it provides a minimum radius of calculation for the rounding of surfaces of 1.5 mm. For a household appliance this is a very decent result.
Comments about PosiTector models
In the family of this manufacturer, version 6000 deserves special attention, which differs from the combined principle of operation. Users mark both effective measurement by ultrasonic method, and support of calculation according to the principles of magnetic induction. Such devices are recommended for maintenance of non-ferrous and ferrous metals, since in both cases accurate and fast results are provided. In addition, the thickness gauge of the PosiTector is renowned for its modern ergonomics. Speech in this case is not only about the design merits, but also about the means of controlling the functions of the device with improved navigation. And this is not counting the automatic calibration and abundance of indicators, informing about the performance of the device.
Comments about MEGA-CHECK
Users of the devices of this company have proved themselves for several performance characteristics. First of all, the developers tried to protect the device as much as possible from external influences, that's why it is possible to use the technique both at home and at the construction site with threats of accidental strikes. Also, this device is used to measure the thickness of the car paint and piping. In these areas, increased accuracy of measurements is required and, according to the owners of MEGA-CHECK devices, these requirements are fully justified.
It must be said that the high cost of ultrasonic measuring instruments forces us to approach the choice of the model responsibly. By the way, even the simplest modifications with a minimal set of additional functions can cost about 20 thousand rubles. Accordingly, to choose an ultrasonic thickness gauge you need with a clear understanding of the tasks that will be solved with its help. What is the main thing in choosing this device? The basic characteristic is the maximum height of the coating, which in principle is able to fix the device. On average, it is 2-4 mm. Then pay attention to the deviation from the actual results - that is, the accuracy of the readings. This value varies from 3 to 10 μm, which is equivalent to one hundredths of a millimeter. As additional parameters it is also necessary to specify the form factor, the methods of providing data, the function of storing measurements and other optional inclusions.