SU996927A1 - Device for checking steel article mechanical properties - Google Patents

Description

(54) DEVICE FOR CONTROL OF MECHANICAL PROPERTIES OF STEEL PRODUCTS

The invention relates to the means of controlling the quality of materials and products and can be used to control the mechanical properties, such as hardness, of steel products by the maximum magnetic permeability.

A device for controlling the mechanical properties of steel products is known, comprising a current pulse generator connected to a magnetizing solenoid, series-connected ferrosonde gradiometer and measuring channel l. .

Although this device allows measuring the residual induction on the surface of a ferromagnetic object magnetized by the pulsed field of a solenoid, it does not solve the problem of controlling the mechanical properties of high carbon steels after quenching, since the output signal is not determined by the maximum magnetic permeability of the material of the products being tested.

Closest to the invention is a device for monitoring the mechanical properties of starch products, containing a current source connected to a solenoid, after which the magnetizing field sensor, dividing unit, switch, key, peak detector and indicator, magnetic induction sensor . In this device, the maximum values of the magnetization field and induction are recorded, as a result of dividing which I fix dts

10 values of amplitude permeability and 2-22S2.

moix This device allows you to define

magnetic permeability value

15 of the material of the controlled product at a given amplitude value of the magnetized field. To do this, it is necessary to carry out many measurements at different amplitudes on a magnetising field. The maximum of the obtained values of amplitude magnetic permeability will be characteristic-. Measure the value of maximum magnetic permeability C23.

25

A disadvantage of the known device is its low productivity and reliability of control, associated with the need for multiple measurements at different amplitudes of magnetizing pulses to determine the maximum magnetic permeability.

The purpose of the invention is to increase the reliability and performance of the control.

The goal is achieved by the fact that the device is supplied in series, connected by a differentiator and a comparator, the output of which is connected to the second key input, and the input of the differentiator is connected to the output of the magnetizing field sensor

In a preferred embodiment of the device, the field sensor is designed as a resistor included in the magnetizing circuit and the induction sensor in the form of a coil and an integrator connected to each other. Hall sensors or flux-probes with appropriate power supply circuits, filters, and rectifiers can also be used as induction sensors and the floor.

Figure 1 shows the structural diagram of the device (the preferred implementation); in FIG. 2, the change in the magnetizing field under control, 5 — the change in induction from the product during control, c — the change in the ratio of the signal from the induction sensor to the signal from the field in control, d is the signal at the output of the differentiator in control.

The device contains a current source 1, a solenoid 2, a resistor 3 serving as a magnetizing field sensor, an induction sensor from the product consisting of a coil 4 and an integrator 5, a dividing unit 6, a differentiator 7, a comparator 8, a key 9, a peak detector 10 and an indicator 11 Position 12 indicates a controlled product. Current source 1, solenoid 2 and resistor 3 are connected in series. The coil 4 and the induction sensor integrator 5 are interconnected. The induction sensor is connected to the second input of the dividing unit 6, the first input of which is connected to the connection point of the solenoid 2 and resistor 3, and the output through the switch 9 and the peak detector 10 is connected to the indicator 11. Comparator 8 is connected between the second input of the switch and the differentiator 7, whose input connected to a point, connecting the solenoid 2. and the resistor 3.

The device works as follows.

Claims (2)

A converter consisting of a solenoid 2 and an induction sensor coil 4 is mounted on the surface of the monitored product 12. A current source 1 supplies a current pulse to the solenoid, the amplitude of which is sufficient to bring the monitored product to magnetic saturation in the control zone. At the output of the sensor floor, i.e. at the point of connection of solenoid 2 with resistor 3, the signal has the form shown in fig.2c1. The instantaneous values of this signal at each instant of time characterize the magnitude of the magnetizing field N. The time interval T, T23 corresponds to an increase in the magnetizing field from zero to a maximum value of 2 3 — to a decrease in the magnetizing field from the value H to zero. The output of the induction sensor signal has the form shown in Fig.26. The instantaneous values of this signal at each time point characterize induction B c. controlled product. The time interval T- ,, Tj J corresponds to an increase in the induction from the product from zero to the maximum value B, 3 to the decrease in induction from the product from the maximum value B "1 TO the value of residual induction B2 The signal at the output of the division block 6 is proportional to the ratio of the instantaneous values of the signals at its inputs . Dividing unit 6 performs the operation of dividing the signal at its second input (i.e., the signal from the induction sensor) by the signal at its first input (i.e. by the signal from the field sensor). With the passage of the magnetizing pulse, the signal at the output of the division block b has the form shown in Fig. 2B. During the time interval T i, 12, corresponding to an increase in the magnetizing field, this signal U t) first increases to the value U ,, and then decreases. The voltage value Uffi is proportional to the maximum magnetic permeability of the material of the product under test. During the time interval T 2, the signal at the output of the division block b increases indefinitely to saturation, since the signal at the second input of the dividing unit tends to a value proportional to the residual induction from the controlled product, and the signal at the first input of the dividing unit tends to zero. The signal at the output of the differentiator 7 in the control is shown in figure 2 g. At time T, when this signal exceeds zero, the comparator B is triggered and opens the key 9. The input from the peak detector unit 10 is input to the input of the peak detector 10. At time Tj, when the magnetizing field has a maximum value of H, the signal at the output of the differentiator becomes zero. At this point in time, the comparator triggers again and closes the key. The input of the peak detector 10 is supplied with voltage from the output of the division block b during the time interval t, T. The maximum value of this voltage is recorded by the indicator 1 Based on the registered value of the voltage Vfnof. it is judged on the mechanical properties (hardness) of the material of the product. The measurement process is complete. On products of the same geometric shape, the registered value of the voltage U is determined only by the value of the maximum magnetic permeability yUn, ax of the material of the product. Improving the reliability and performance of the Lyotista Control is achieved by eliminating the need for multiple measurements at different amplitudes of magnetizing pulses to obtain a signal, the magnitude of which is determined by the maximum magnetic permeability x of the material of the product being tested. Claims An apparatus for monitoring the mechanical properties of steel products, containing a current source, connected to a solenoid, serially connected magnetizing field sensor, dividing unit, key, peak detector and indicator, magnetic induction sensor connected to the second input of the dividing unit, characterized in that In order to increase the reliability and performance of the control, it is equipped with a series-connected differentiator and comparator / whose output is connected to the second key input, and the input entsiatora sensor connected to the output of the magnetizing field. Sources of information taken into account during the examination 1. USSR author's certificate 331303, cl. G 01 N 27/80, 1969. 2. Authors certificate of the USSR 460520, class, G 01 R 33/12, 1972 (prototype).