SU1434296A1 - Apparatus for dynamic calibration of pressure transducers - Google Patents

Abstract

The invention relates to a measurement technique, in particular, devices for producing single pressure pulses for calibration, verification and dynamic testing of pressure transmitters. The aim of the invention is

Description

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increase accuracy. The device contains a working 1 and specifies 2 cameras. The chambers are connected by a channel 5 to a valve 6, equipped with an elastic metal rod 7 with an annular groove 8, which includes the ends 9 of the grippers 10, located on the platform 11, which is equipped with an eccentric 14 with an actuator 15. The other end of the rod is connected to the tension unit 24. When closed valve position

6, tension unit 24 stretches the rod. Chamber 2 creates pressure controlled by a pressure gauge 23. By turning the eccentric 17, the sleeve 16 moves from the valve needle, folding the ends 9 of the grips 10, which causes the valve 6 to open abruptly and create a peak pressure in the working chamber 1, where the calibrated 3 and exemplary 4 sensors are located pressure, 1 Il.

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The invention relates to a measurement technique, in particular, to devices for producing single pressure pulses for calibration, verification and dynamic testing of pressure transmitters.

The aim of the invention is to improve the accuracy.

The drawing shows the proposed device.

The device contains a working 1 and specifies 2 cameras. In the working chamber there are jacks for graduated 3 and for example 4 pressure sensors. The chambers are connected by a pinch 5 to a valve made in the form of a needle 6 with a saddle, the needle being provided with an elastic metal rod 7 with an annular groove 8. The groove 8 includes the ends 9 of the grips 10, installed symmetrically with respect to the rod 7 on x 12 located between the ends 9 and 13 of each capture. The platform 11 is equipped with an eccentric 14 with an actuator 15 fixed in the wall of chamber 2. The ends 9 of the grippers, which are included in the groove 8, are covered from the outside with a movable sleeve 16 that is moved by the eccentric 17 with a handle 18. In the chamber 19 opposite to the needle 2, an adjustable stop 20 is attached with a limb and a seal 21. A collar 22 is placed at the second end of the rod. A pressure supply with a pressure gauge 23 is provided to the driver chamber 2. The second end of the rod is connected to the tension assembly 24. A pressure gauge 25 is installed in the working chamber.

The device works as follows.

With the needle of the shut-off valve 6 open, the working medium with a predetermined static pressure is supplied to the control chamber 2. The same pressure is established in the working chamber 1. By turning the eccentric 17, the sleeve 16 moves to the needle and its end

brings to the center the ends 9 of the claws 10, which, with their working projections, set into the groove 8 on the rod 7. By turning the knob of the cam 14, the platform 11 is fed to the needle 11 and through the working surfaces 9 of the grips moves the needle 6 to close the channel 5 connecting chamber 1 and 2 In this position, grip, wedging from

the vertical force directed from the locking needle 6 to the rod, securely hold the needle 6 in the closed position, sealing the cavities of the chambers 1 and 2 from each other. In the cavity

The working chamber 1 establishes the static pressure of the working medium, controlled by a pressure gauge 23. In the cavity of the driver chamber 2, the desired static pressure is generated, controlled by a pressure gauge 22. By activating the tension assembly 24, the stem 7 of the locking needle 6 is pulled by the gap S within the elastic deformation of the stem. Adjusting the size of the gap S over time is needed even with the same material.

rod and its size due to the phenomenon of relaxation (creep) of the rod material. The specified static pressure difference in chambers 1 and 2 is determined by

It makes accuracy according to the magnitude of the pressure pulse amplitude and depends only on the accuracy class of installed pressure gauges 23 and 25. At the moment of contact of the collar 22 with the stop 20, a signal is given (for example, turning on the signal lamp) and turning the eccentric 17 sleeve 16 moves from the needle 6, the ends 9 grippers 10. The working surfaces 9 of the grippers 10, moving along arcs of equal circles centered on the axes 12, hold the locking needle 6 in the closed position until the edges of the bearing surfaces of the groove 8 break from the edges of the working surfaces there are 9 grips 10. A sharp withdrawal of the locking needle occurs at a speed equal to the speed of propagation of longitudinal vibrations in the metal rod 7 of the locking needle 6, since the speed of sound in a metal (solid) is always higher than the speed of sound in a liquid or gas, it can be considered that the maximum possible rate of rise of the pressure pulse front is obtained for these working media. The pulse created in the working medium (without any additional distorting pulses from shocks, explosions and the like d) affects the model 4 and believed emye 3 pressure sensors installed in the chamber 1.

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Claims (1)

Invention Formula An apparatus for dynamically calibrating pressure sensors, comprising a working chamber with sockets for graduated and exemplary pressure sensors, and defining chambers connected by a channel to a needle-like valve with a saddle, the needle being provided with a rod and a retaining, lowering and recharging needle, while the needle with the rod and the holding and lowering mechanism is placed in the master chamber, characterized in that, in order to increase the accuracy, there is a rod in it; made of elastic metal with an annular groove at the first end connected to the needle; the holding and lowering mechanism is designed as a swivel grips with a lock, while the grippers are symmetrically mounted relative to the rod on the axles fixed on the movable platform, and the end of each gripper enters the annular groove on the rod, and the lock is designed as an axially movable axially and embracing the movable platform with crowded crowns of the sleeve; Entrics, one of which is in contact with the sleeve, and the other with a movable platform, while the platoon mechanism is fulfilled as a tension assembly associated with the second end of the rod.