SU1229324A1 - Downhole profile meter - Google Patents

Description

The invention relates to geophysical well survey devices and can be used to measure the cross-sectional profile of a well bore.

The purpose of the invention is to demonstrate the accuracy and reliability of the device.

FIG. 1 shows the proposed device, a general view of FIG. 2 - displacement transducer, top view; Fig. 3 shows a section perpendicular to the axis of the drums and passing through the ends of the measuring levers.

The device consists of a housing 1, to which the measuring levers 2 are hinged. The free end of the lever in contact with the borehole wall 3 is rigidly connected to the flexible element - cable 4, the other end of the cable is fixed on the outer screw surface of the drum 5, the cable 4 is laid in the threaded grooves the drum in such a way that the perpendicularity of the axis of the drum is observed, the Baraban is mounted on an L-shaped roller 6 and is co-aligned with it by means of a key (not shown). By means of a pin, rotation is transmitted to the L-shaped roller 6 from the drum, and also the movement of the drum along the roller is ensured. The roller 6 is located in the cantilever housing and rotates in a support made of ball-bearing holders 7. A spiral spring 8 is attached to the roller, creating a torque to release the strut.Ha of the protruding part of the roller is a permanent magnet 9 for controlling the measuring transducer Yu The measuring transducer 10 is made in the form of a set of reed relays 11, evenly spaced around the circumference (figure 2). The middle of the relay (the point of contact of its plates) is located on the circumference described by the permanent magnet 9 when the roller 6 rotates. The measuring arms of the levers 2 are pressed against the well wall by a spring 12. The reed relays are connected in series within each measuring transducer and are bounced by ohmic resistance, the contrasts are different and evenly

increase,. At the output of the measuring transducer with such a scheme, the signal is represented in analog form (changes in the current value depending on the number of closed relays). The device is launched into the borehole on a geophysical cable 13.

The device works as follows: m.

Having lowered the device into the measurement zone, a signal is given from the surface to the opening of the measuring levers (not shown).

lifting device. Under the action of the spring 12, the measuring levers 2 rotate up to the stop against the borehole wall, unwinding the cable 4 from the drum 5. At the same time, the L-shaped roller 6 also rotates the drum 6, the magnet 9 of which alternately closes the contacts of the measuring transducer 10 At the output of the converter 10 with

This is a signal (electric current), the value of which is proportional to the amount of short circuit of the relay in one direction. Since the elasticity of the spring 12 is greater than the elasticity of the spring

8, the cable 4 is constantly in a tensioned position. Thus, the magnitude of the opening of the measuring steps, i.e. the size of the profile to be measured is equal to the length of the cable reeled from the drum. The size of the diameter in two mutually perpendicular directions is expressed as 1 + d + l, and D,., Lj + d + 1 (Fig, 3), where d is the size between the bar axis; eleven

the size of the opening of the measuring levers.

Since the cable on a length of 400–450 mm and at a force of 200–300 g is almost inextensible, the accuracy of the device is determined by the discreteness of the reed switch 11. With a drum diameter d of 8–10 mm and an outer diameter of the measuring converter d 20–25 mm ( Fig. 2 and 3.) The sampling resolution can be achieved up to 1 mm. With such characteristics of the device, the accuracy of determination is mm profile.

Figg

Phage. 3

Claims (2)

1. Borehole profiler, comprising a housing, spring-loaded measuring levers, a transmission mechanism with a flexible element connected to the measuring lever, and a displacement transducer, characterized in that, in order to improve the accuracy and reliability of the profiler, the transmission mechanism of each measuring lever is equipped with a drum, a roller and a spiral spring, and the drum is mounted with the possibility of longitudinal movement on the roller, which is connected by means of a spiral spring to the housing, while on the drum on rezbovay groove, wherein the flexible element is arranged. 2. Profiler according to claim 1, wherein the roller is made L-shaped with a permanent magnet for interaction with the displacement transformer. T TlS ^{, No.}