SU976045A1 - Device for closing valves of deep-well sampler - Google Patents

Description

(54) DEVICE FOR CLOSING THE VALVE Borehole sampler

The invention relates to oil (industrial, and more specifically to well testing. A device for closing the downhole sampler valves is known, comprising a chamber, a piston chamber, a piston with a STOCK, a spring, and a SCREW setting. This device is activated at a depth under the action of well pressure due to presetting the pressure switch on the sampling interval pressure C1. The disadvantage of this device is smoldering and the reliability of the structure is low. A device for closing the depth valves is known sampler containing a housing, a lever system, and then a valve with a check valve. This device is activated by the pressure differential that occurs when the sampler is raised inside and outside its housing 2. The disadvantage of this device is low reliability and poor quality sampling. This is due to the fact that when installing a lubricator with a sampler, gas and liquid mixtures often leak through the valves of the fittings, as well as the packing device of the lubricator itself. As a result, a pressure differential occurs in the lubricator, sufficient to trigger the device. In this case, the sampler is lowered into the well with the valves closed and the sample taken by it will not match the sample from the investigated depth. The closest in technical essence is a device for closing a downhole sampler valve, comprising a hollow body, running down a cable, a lever system, a check valve, which, in order to ensure operation reliability, is provided with a bellows connected to the sampler valve through the lever system, and STOCOM, rigidly connected to the valve and interacting with a check valve placed in a duct made in the bellows and communicating with the outside space the internal cavity of the housing and a set of disks arranged However, this device has low reliability and does not provide high-quality sampling. This is explained as follows. When installing a lubricator with a sampler, there is often a leak of gas from the standby mixture through the valves of the fittings, as well as the packing device of the lubricator itself. As a result, a pressure differential occurs in the lubricator sufficient to operate the device. In this case, the sampler is lowered into the well with the valves closed and the sample taken by it will not correspond to the sample from the depth studied. The aim of the invention is to improve the reliability of the device and improve the quality of sampling. The goal is achieved by the fact that the device for closing the downhole sampler valves, comprising a hollow body, descending on a cable, a lever system, a check valve, a bellows associated with the sampler valve through the lever system, a set of discs located in the internal cavity of the Sa, and the stem, which is rigidly connected to the sampling valve and interacting with a non-return valve, is equipped with a separator with a seat and a travel stop, installed in the upper part of the internal cavity of the housing and with a disconnecting node of a compulsory action, executed in the form of upper and lower spring-loaded couplings, in the cavity between which there is a pear-shaped part for fastening the cable, passed through hole, made in the upper part of the body, and in the lower part of the lower coupling, there is a locking element associated with the separator saddle . The presence in the upper part of the device for closing the valves of the shut-off node of the forced action allows to ensure the reliability of the device and high-quality sampling by eliminating the pressure drop in the device body when mounting the lubricator. The drawing shows a device for closing the downhole sampler valves. It comprises a housing 1 with an internal cavity 2 with a set of disks 3 placed in it, a check valve 4, a bellows S with channel 6, a lever system 7 and a rod 8 rigidly connected to the valve 9 of the sampler, the upper part of the housing 1 of the device is equipped with the shut-off unit of compulsory action, containing the upper 10 and lower 11 couplings, spring loaded 12, in the cavity between which there is a pear shaped part 13 for fastening a cable passed through a through hole in the upper part of the body 1. A complete locking element 14 is coupled to the saddle 15, made in the separator 16, located in the upper part of the cavity 2. Under the separator 16 there is a travel stop 17. The device for closing the valves works as follows. Before mounting the lubricator, inside which the sampler is located, the shut-off unit of forced action is pulled by a cable passed through a through hole in the upper part of the body. In this case, the locking element 14 of the lower coupling 11 will assume a position in which the lower part of the cavity under the separator 2 will have an end-to-end communication with the environment surrounding the sampler, both through the non-return valve 4 and through the opening in the upper part of the device for closing the valves. When the sampler is lowered into the well, the locking element 14 is returned to the position, with KOTODOM it sits in the saddle 15 of the separator 16 and, thus, separates the lower part of the cavity 2 from the surrounding cavity through the hole in the upper part of the body. The sampler with the device is lowered into the well to a depth exceeding the sampling depth of 5 m. When the sampler is lowered, the gas-liquid mixture passes through channel 6 and the check valve 4 into the cavity 2. When the sampler stops, the pressure in the working chamber and outside is equalized, and the check valve 4 closes. When the sampler is raised 5–10 m (up to the sampling interval), the pressure in cavity 2 will be higher than the outside. Under the action of the pressure differential, the bellows 5 moves downwards and, interacting through the lever system 7 with the valve 9 of the sampler, releases the valve 9 and causes it to mix upwards. Together with the valve, the rod 8 is stirred up, which opens the valve 4, as a result of which there is a gradual decrease in pressure

cavities 2, as the sampler rises. The presence of a set of disks 3 makes it possible to reduce the rate of gas dissolution in a liquid, while maintaining the volume of the gas phase in the cavity 2 of the device, which makes it possible to reduce the sampling lift of the sampler.

This device for closing the downhole sampler valves allows, in comparison with the known technical solutions, the reliability of its operation and the possibility of objectively determining the parameters of oil by taking high-quality samples.

If a known device operating on the basis of differential pressure as a result of a pass in the lubricator triggers and the sampler is lowered into the well with valves closed, then the sampled sample will not correspond to the sample from the specified depth, while the sampler with the proposed device is guaranteed to work at the specified depth at a pressure drop of 1-2 kgf / cm, i.e., when it is raised to 1O - 20 m from a predetermined depth. This allows more accurate determination of the parameters of reservoir oil and reduces the number of idle tripping for sampling by the sampler.

In the oil and gas industry, the use of the proposed invention, in comparison with the known technical solutions, allows one to obtain more complete and reliable data characterizing the properties of the reservoir oil when calculating oil reserves, designing the development of oil deposits and selecting the optimal direction of well operation.

Claims (3)

1. Mamuna V.N., et al., Depth samplers and their application. M., Gostoptehizdat, 1961, p. 29-ZO. 2. USSR author's certificate No. 149734, cl. E 21 V 49/08, 1961. 3. USSR author's certificate No. 38174О, class Е 21 В 49 / О8, 1970. .. .; .... .Ni ,. V  ,