RU132209U1 - DIAGNOSTIC DEVICE FOR PARTS FROM POLYAMIDE MATERIALS - Google Patents

Abstract

A device for diagnostics of parts made of polyamide materials, consisting of a desktop, a drive for generating pressure, a controller for diagnostic parameters, characterized in that it contains a high-frequency working capacitor, including a working table connected to a lower grounded plate and having the ability to move, the upper high-potential mobile a stove, a controller equipped with a sensor system, a power regulator and a protective screen.

Description

The device relates to the field of diagnostics of parts and structures made of polyamide materials, in the manufacture and after their operation.

A known method of vibro-acoustic control of composite and multilayer products from metals and plastics, as well as a device for its implementation (US Pat. RF No. 2455636, IPC G01N 29/04, announced 11/23/2010).

A device for vibro-acoustic control of products consists of a device for exciting elastic vibrations and a piezoelectric sensor, a control pulse amplifier, an analog-to-digital converter (ADC), a digital-to-analog converter (DAC), and a personal computer with an installed application package.

The essence of control consists in the fact that sequentially excite elastic vibrations and load the local zones of the controlled product with the attached mass, forming an oscillatory system "product section - attached mass", the vibration parameters are recorded and the presence of the defect and its location are judged by the dependence of the vibration parameters on the location of the attached mass in the product.

The disadvantages include the need for mechanical action on the part, the complexity of the equipment and the low accuracy of control of parts made of polyamide materials.

A known ultrasonic method for determining the strength characteristics of polymer composite materials (US Pat. RF No. 2461820 IPC G01N 29/04, claimed 05/11/2011). Two ultrasonic direct broadband transducers and a personal computer with the installed software package act as a device.

The device for implementing this method contains two transducers located on one or from different sides on the surface of the controlled product, at a certain distance from each other, which excite and receive pulses of ultrasonic vibrations, the resulting pulse spectrum (determines) characterizes the strength characteristics of the polymer. The device converts the pulses by exciters, then receives pulses, ultrasonic vibrations of witness samples, after their production measures the pulse spectra, after which the samples are subjected to mechanical, thermal and other damaging effects that simulate operational loads, the device uses transducers to repeatedly excite, receive and measure pulse spectra passed in the polymer composite material of witness samples. The strength characteristics of the controlled product is determined by a certain correlation.

The disadvantages include the complexity of the diagnosis of spatial products. In addition, the device does not allow to determine the size and location of defects.

The method of tensile testing of glass-filled polyamide separators and the non-destructive testing device for polyamide separators that are part of the roller bearings of axlebox units KS 221A (form MKIY.427158.002FO) found wide application in railway transport. The device is a unit on the upper surface of which a rotating platform and a transducer are installed. Separation of separators into suitable and unsuitable is carried out by means of automatic tolerance control of the deflection of the horizontal jumpers of all 15 windows of the controlled separator by applying the same bursting forces to these jumpers. A movable measuring transducer fixes the displacement of the rod of the pneumatic cylinder, which creates the necessary bursting force. Based on a comparison of the values of 15 movements, a conclusion is drawn about the validity (unsuitability) of the controlled separator.

The main disadvantage of the KS 221A device is that the tested separator is subjected to mechanical stress, which leads to the development of existing latent defects.

The closest analogue is the installation for tensile testing of polyamide bearing cages UISA-2M (Maintenance and repair of passenger cars / Thematic selection / L-37- (253) -TP-100-2004 Appendix 1). The separator is stretched to increase the outer diameter by 1 mm.

The installation consists of three-position levers, a pressure gauge, an indicator, a ring with rollers, a rod cavity, a piston cavity, a pneumatic actuator and a four-section ring.

Tensile testing of separators made of polyamide is carried out as follows. Before testing the separator, the first three-position lever is tilted, the second is closed, air flows through the pneumatic drive into the stock cavity and lifts the ring with rollers. In this position, the four-section ring has an outer diameter smaller than the inner diameter of the tested separator. Then the separator is mounted on the ring, the first lever is closed, the second is opened. Through a pneumatic actuator, air leaves the rod cavity, while simultaneously entering the piston cavity. The ring with rollers is lowered into a four-section ring, stretching it. The outer diameter of the ring becomes larger than the inner diameter of the separator by 1 mm. Thus, one side is checked. A polyamide separator is considered serviceable if it has not collapsed during the test, and a visual inspection did not reveal defects or deviations from the technical conditions.

The disadvantages include the fact that when stretching the UISA-2M separator, the development of latent defects increases, which makes the separator unsuitable for further use. The installation does not allow to specifically identify the nature of the defect (crack, moisture, foreign inclusions).

The technical task of the proposed device is to increase the accuracy of diagnostics without mechanical impact on the object of control, reducing time and cost of testing.

To solve this problem, a device for detecting defects in products made of polyamide materials (PA SV. 30-1 ETM, PA 6-210 / 310, PA 610 L, etc.) is claimed. The essence of the device is to determine the physico-mechanical parameters of polyamide materials by creating a penetrating electromagnetic field.

A device for diagnostics of parts made of polyamide materials, consisting of a desktop, a drive for creating pressure, a controller for diagnostic parameters, characterized in that it contains a working capacitor that includes a desktop connected to a lower grounded plate and having the ability to move, an upper highly potential movable plate , controller equipped with a sensor system, power regulator, protective screen.

The essence of the installation is illustrated by drawings.

The figure 1 presents a General diagram of a device for the diagnosis of products from polyamide materials

The figure 2 presents a diagram of the working capacitor of the device for the diagnosis of products from polyamide materials

The figure 3 presents the electrical circuit of the device for the diagnosis of products from polyamide materials (passport of the electrothermal installation UZP2500A Appendix 2)

The figure 4 presents the experimental data of the diagnostic parameters of the sample of polyamide with metal inclusions

In Fig.1, a device for the diagnosis of products made of polyamide materials. consists of a working capacitor (1), a timer (2), a drive for generating pressure (3), a generator (4), a voltage regulator (5), a controller for diagnostic parameters (6), an ammeter (7), a feeder (8) , a protective screen (9).

In Fig.2, the working capacitor of the device for diagnosing products made of polyamide materials includes fixing nuts (10), upper (11) and lower (12) working plates (the upper high-potential is power, the lower remains stationary during the diagnostic process), the worker table (13) electrodes (14, 15), control object polyamide separator (16).

In Fig. 3, the electrical circuit consists of a working capacitor (1), a press drive (3), a generator (4), a variable capacitor (17), a heating transformer for the generator lamp (18), a control panel (19), a protective shield drive (20 ) and power key (21).

Figure 4 presents the abrupt increase in the anode current (1, 2, 3), which indicates the presence of metal inclusions in the test sample.

A device for the diagnosis of parts made of polyamide materials works as follows. Connect the generator (4) to the network. The upper plate (11) of the device is lowered and fixed with nuts (10) in such a way that its surface abuts against the controlled part (16) (for example, a polyamide roller bearing cage) and electrodes (14, 15), the diagnostic time is set on the relay (2) . Then the separator is covered with electrodes along the upper, lower and inner side surfaces of the partitions, thereby creating working capacitors, where the separator material (polyamide) acts as a dielectric. The control object (16) and electrodes (14, 15) are placed on the device desktop (13) in the space between the high potential (11) and the grounded (12) plates.

Lower the press (3), close the protective shield (9). Next, they start the working registration program, turn on the generator (4), maintain the set time, then the installation automatically turns off, the protective screen (9) opens.

The proposed device was tested on samples of glass-filled polyamide brand "Armamide", size 5 × 6 × 50 mm The equipment used was the installation of the UZP-2500 model. The parameters of the anode current of the generator were monitored using sensors. Acoustic sensors mounted along the outer perimeter of the working capacitor recorded the occurrence of microdischarges on the surface of polymers. The use of low-frequency filters allowed us to distance ourselves from external interference, and the location-based method for calculating the incoming signal made it possible to determine the location of the emerging signals. The measurement data were transmitted to the computer using the controller. In addition, the controller, according to the readings of the sensors, regulates the entire diagnostic process. Using a working software product allowed to obtain data in real time. After analyzing the data obtained, it is possible to identify changes in the physicomechanical characteristics of polymer materials by the nature of the change in the anode current. So, for example, the dynamic abrupt increase in the anode current (Figure 4) corresponds to the presence of metal inclusions in the test sample. A dynamic increase in current, followed by a fairly rapid decrease in it, allows one to diagnose the presence of increased moisture and microcracks in the polymer under study.

As a result, the device determines the state of the monitoring object by the readings of the anode current, which are displayed on the monitor screen in the form of graphs.

The application of the proposed installation to determine the physicomechanical parameters in parts made of polyamide materials, which is distinguished by the simplicity of the design and setup, will allow more accurate diagnosis without mechanical impact on the test object, reliably determine the nature of the defect, and also reduce the time and cost of testing .

Claims (1)

A device for diagnostics of parts made of polyamide materials, consisting of a desktop, a drive for generating pressure, a controller for diagnostic parameters, characterized in that it contains a high-frequency working capacitor, including a working table connected to a lower grounded plate and having the ability to move, the upper high-potential mobile a stove, a controller equipped with a sensor system, a power regulator and a protective screen.

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