Ultrasonic nondestructive testing technique is used to control metal, polyethylene, concrete, welded joints, cast billets and steel casting, heating pipes, water pipes, gas pipes, boiler quality, welded rail joints, pipes, forgings, and others. Ultrasonic testing of pipes and conduits is an effective non-destructive method quality control of pipelines, diagnosis of defects of pipes, water pipes and heating mains without decommissioning. Ultrasonic method of quality control of pipelines enables the full range of ultrasonic diagnostics of pipelines, identify weaknesses welds, internal corrosion of heating pipes and water pipes. When using this method excludes conventional error, as well as errors due to volumetric distribution of the electromagnetic dynamic forces in the surface layer of the object of control. Timely and planned elimination of damaging pipeline sections will save on repairs in an emergency. Ultrasonic thickness gauge measures the transit time of the pulse from the transmitter to the opposite surface of the object and control back to the transducer. To conduct such measurements access to the opposite surface of the object of control is required. Because of this, if the opposite surface of the object of control is completely inaccessible or unavailable, the need to cut the object of control, which is required when using a micrometer or caliper, is absent.
Preparation of the gauge to the control begins with selecting the most suitable converter. Excitation and reception of elastic waves is performed by converting electrical oscillations into acoustic, and then back to the acoustic power with the help of special devices - piezoelectric transducer having a sensing element - piezoceramic plates. The instrument includes a caliper 6 ... 8 RS converters for the control products for different ranges of thicknesses (from 0.6 mm to 10.0 ... 1 ... 1000 mm), with varying surface roughness and the curvature (minimum radius of curvature of 3.0; 5 0 and 10.0 mm for different transducers). Then configures the gauge measuring unit - the most accurate way of setting - two samples made of material products and corresponding minimum and maximum measured thickness. Setting'' zero transducer '' was performed on a thin sample, and setting the speed of sound - on thick. These settings are repeated as long as the digital display will not exact values of the sample thickness. Configure the measuring unit may also be attached to the device for the samples, and then perform setting of the speed of sound in the area of products available for measuring the mechanical measuring means or the sample material from the product. Operative check the gauge after setting the speed of sound in two samples was carried out by measuring the thickness of a set of samples attached to the device or specially manufactured and tested. The measured values must not deviate from the nominal thickness of the samples is greater than indicated in the data sheet of the thickness gauge.