RU2367917C1 - Method for measurement of torsion torque of threaded joint tightening and torque spanner for its realisation - Google Patents

Abstract

FIELD: physics, measurement.

SUBSTANCE: invention is related to measurement equipment and may be used for monitoring of torsion torque of threaded joint tightening. Method consists in application of torsion torque to tightened threaded joint, change over of threaded joint from state of rest to state of motion, rotation by a certain angle, which does not exceed 2÷4° and measurement of torsion torque, when rotation angle reaches specified value. Besides additional turn is carried out by the same angle with measurement of torsion torque, when rotation angle reaches specified value, and torsion torque of tightening is identified as difference of doubled value of torsion torque at initial rotation by specified angle and value of torsion torque in case of additional rotation by specified angle. Device comprises torque metre connected to inlet of amplifier, outlet of which is connected to inlet of analog-digital transducer, the first and second memory register, pulse counter, decoder, calculation unit, digital indicator and element "OR".

EFFECT: higher accuracy of tightening torsion torque monitoring.

3 dwg

Description

The invention relates to measuring technique and can be used to control the tightening torque of threaded connections.

A known method of measuring the tightening torque of the threaded joints is applied to the tightened threaded joint of the torque, the translation of the threaded connection from the rest state to the motion state, rotation by a predetermined angle not exceeding 2 + 4 °, and measuring the torque when the rotation angle reaches the specified value (see a.s. No. 1500881, publ. 08/15/89).

However, the use of this method does not allow precise determination of the tightening torque, since the torque corresponding to the rotation of the threaded connection by an additional angle is measured, therefore, an error arises in measuring the tightening torque.

The technical result of the invention is improving the accuracy of the control torque.

The technical result is achieved by the fact that according to the method of measuring the tightening torque, which is applied to the tightened threaded connection of the torque, the translation of the threaded connection from the rest state to the motion state, rotation by a predetermined angle not exceeding 2-4 °, and measuring the torque when the angle of rotation reaches the set value, an additional rotation is made at the same angle with the measurement of torque when the angle of rotation reaches the set value, and the torque is m Tightening torque is defined as the difference between the doubled value of the torque at the initial rotation by the specified angle and the value of the torque at the additional rotation by the specified angle.

Known torque wrench containing a torque sensor connected to the input of the amplifier, the output connected to the input of an analog-to-digital Converter, and the first memory register (see patent RU No. 2296964 from 04/10/2007).

The disadvantage of this key is the insufficiently high accuracy of measuring the tightening torque of threaded connections.

The technical result of the invention is improving the accuracy of measuring the torque of the tightening of threaded joints.

The technical result achieved is achieved by the fact that a torque wrench containing a torque sensor connected to the input of the amplifier, an output connected to the input of an analog-to-digital converter, and the first memory register is equipped with a rotation angle sensor, a second memory register, a pulse counter, a decoder, a calculation unit, digital the indicator and the OR element, the output connected to the input of the first indicator, the output of the angle sensor is connected to the counting input of the pulse counter, the outputs connected to the decoder inputs a, the information outputs of the analog-to-digital converter are connected to the corresponding information inputs of the first and second memory registers, information outputs connected to the corresponding information inputs of the computing unit, information outputs connected to the digital indicator inputs, the first decoder output is connected to the “Record” input of the first memory register, the second decoder output is connected to the “Record” input of the second memory register, the zero and the first decoder outputs are connected to the elem OR-coagulant, a second output connected to an input of the decoder "Calculation" computing unit and the second input element of the indicating and adjusting inputs of the memory and registers of the pulse counter via a control button connected to the bus "voltage logic one".

Figure 1 shows a graph of the dependence of torque on the angle of rotation of the nut when tightening the threaded connection.

Figure 3 shows the block diagram of the torque wrench.

Figure 2 - General view of the torque wrench.

The torque wrench contains a torque sensor 1, a rotation angle sensor 2, a torque sensor 1 through an amplifier 3 is connected to the input of an analog-to-digital converter 4, the first and second memory registers 5 and 6, a pulse counter 7, a decoder 8, a calculation unit 9, a digital indicator 10 and the OR element 11, the output connected to the input of the first indicator 12, the output of the rotation angle sensor 2 is connected to the counting input of the pulse counter 7, the outputs are connected to the inputs of the decoder 8, the information outputs of the analog-to-digital Converter 4 are connected to with the information inputs of the first and second memory registers 5 and 6, the information outputs connected to the corresponding information inputs of the computing unit 9, the information outputs connected to the inputs of the digital indicator 10, the first output of the decoder 8 is connected to the “Record” input of the first memory register 5, the second output of the decoder 8 is connected to the “Record” input of the second memory register 6, the zero and first outputs of the decoder 8 are connected to the inputs of the element 11 OR, the second output of the decoder 8 is connected to the input “Calculation 9 computing unit and the second input of the indicating element 13, and adjusting the inputs of registers 5 and 6, the memory 7 and the counter pulses through the control knob 14 connected to the bus 15 'logic one voltage. "

The method of measuring the tightening torque is as follows. The key head of a torque wrench (not specified) is put on the threaded connection and the threaded connection is rotated. When the angle of rotation reaches the set value 2 ÷ 4 °, a torque measurement is performed. Then make an additional rotation at the same angle, when the angle reaches the set value, a second measurement of torque is performed.

Since the tightening of the threaded joints is carried out within the elastic deformations, the dependence of the torque on the key on the rotation angle has a linear dependence, therefore, knowing the values of the torque at two points, we can calculate the value of the tightening torque as the difference between the doubled value of the torque at the initial rotation by a given angle and torque values for an additional rotation at a given angle.

The torque wrench works as follows.

The key head (not specified), the key is installed on a threaded connection (not specified) and press the control button 14. In this case, the contents of memory registers 5 and 6 are reset and counter 7 is set to zero.

This leads to the appearance of the voltage of the logical unit at the zero output of the decoder 8, the output of the element 11 OR also appears the voltage of the logical unit, which is fed to the input of the first element 12 of the display.

The display element 12 lights up, thereby indicating the start of measurement.

Then, a torque is applied to the threaded connection and the threaded connection is transferred from the rest state to the motion state and rotate it.

In this case, a voltage appears at the output of the torque sensor 1, the value of which is proportional to the value of the applied torque. This voltage is supplied through an amplifier 3 to the input of an analog-to-digital converter 4, which converts the voltage proportional to the moment into a digital code. The digital code from the outputs of the analog-to-digital Converter 4 is supplied to the inputs of the registers 5 and 6 of the memory.

When, when turning the threaded connection, the rotation angle reaches the set value within 2 ÷ 4 °, an impulse will appear at the output of the angle sensor 2, which is fed to the counting input of the counter 7 pulses.

In this case, at the zero output of the decoder 8, the voltage of the logical unit disappears and it appears on the first output of the decoder 8.

The leading edge of this pulse is writing to the code at its inputs, corresponding to the value of the torque at the initial angle of rotation.

With a further rotation of the threaded connection, an impulse will reappear at the output of the angle sensor 2 when the threaded connection rotates the same angle as during the initial rotation. In this case, the counter 7 pulses will be set to the following state, the logical unit voltage will appear at the second output of the decoder, which will record the code corresponding to the torque when the threaded connection is turned to an additional angle in the second register 6 of the memory.

The digital code from the outputs of the registers 5 and 6 of the memory is fed to the inputs of the block 9 calculations.

When a logical unit voltage appears at the second output of the decoder 8, unit 9 performs a calculation in which a code appears at its output corresponding to the value of the difference between the doubled value of the torque at the initial rotation by a given angle and the value of torque during an additional rotation by a given angle. The code from the outputs of block 9 of the calculation is supplied to the inputs of a digital indicator, which displays the calculated magnitude of the torque.

Since the voltage of the logical unit is absent at the first output of the decoder 8, the indicator 12 goes out, which indicates that the torque measurement is completed.

When voltage appears at the second output of the decoder 8, the indicator 13 lights up, which signals that the measurement result can be read.

The measurement of the tightening torque is completed and the wrench is removed from the tested screw connection.

Introduction to a torque wrench containing a torque sensor connected to the amplifier input, output connected to an analog-to-digital converter input, and a first memory register, rotation angle sensor, second memory register, pulse counter, decoder, calculation unit, digital indicator, and OR element, the output of the first indicator connected to the input, while the output of the angle sensor is connected to the counting input of the pulse counter, outputs connected to the inputs of the decoder, information outputs analog-digital of the second converter are connected to the corresponding information inputs of the first and second memory registers, information outputs connected to the corresponding information inputs of the computing unit, information outputs connected to the digital indicator inputs, the first decoder output is connected to the “Record” input of the first memory register, the second decoder output is connected to the input "Record" of the second memory register, the zero and first outputs of the decoder are connected to the inputs of the OR element, the second output of the decoder is connected It is connected to the input “Calculation” of the calculation unit and the input of the second indication element, and the installation inputs of the memory registers and the pulse counter via the control button are connected to the bus “Logic unit voltage”, which made it possible to increase the accuracy of measuring the tightening torque of the threaded connections, since the value of the tightening torque is calculated according to the results of measuring the torque at two points spaced from each other by the same angle of rotation, amounting to 2 ÷ 4 °.

Claims (2)

1. The method of measuring the tightening torque of the threaded connections, which consists in applying to the tightened threaded connection of the torque, the translation of the threaded connection from the idle state to the motion state, rotation by a predetermined angle not exceeding 2 ÷ 4 °, and measuring the torque when the rotation angle is reached a set value, characterized in that they produce an additional rotation at the same angle with the measurement of torque when the angle of rotation reaches the set value, and the tightening torque is determined as the difference between the doubled value of the torque during the initial rotation by a given angle and the value of the torque during an additional rotation by a predetermined angle. 2. A torque wrench comprising a torque sensor connected to an amplifier input connected to an analog-to-digital converter input and a first memory register, characterized in that the torque wrench is equipped with a rotation angle sensor, a second memory register, a pulse counter, a decoder, a calculation unit , a digital indicator and an “OR” element, an output connected to the input of the first indicator, the output of the angle sensor is connected to the counting input of the pulse counter, the outputs connected to the inputs of the decoder, info The rotation outputs of the analog-to-digital converter are connected to the corresponding information inputs of the first and second memory registers, information outputs connected to the corresponding information inputs of the computing unit, information outputs connected to the inputs of the digital indicator, the first output of the decoder is connected to the “Record” input of the first memory register, the second output the decoder is connected to the input "Record" of the second memory register, the zero and first outputs of the decoder are connected to the inputs of the element "AND And, "a second output connected to an input dishifratora" Calculation "computing unit and the second input element of the indicating and adjusting inputs of the memory and registers of the pulse counter via a control button connected to the bus" voltage logic one. "

Images