SU1659629A1 - Check valve for casing cementing - Google Patents

Abstract

The invention relates to the mining industry and is intended for cementing casing strings in a reverse manner. The goal is to increase the reliability of receiving a signal about the end of cementing. In case (K) 1, fins 2 are placed on its inner surface, forming channel 3. Inside K1, a locking element (E) with positive buoyancy in the cement mortar is installed with axial movement. In the upper part of K1 O ate che o y o FIG. one

Description

placed the saddle 5 under the E 4, and in the lower part of the K 1 - fairing 6 of the diamagnetic material. The lower magnet 8 is rotatably mounted in the cavity 7 of the fairing 6. The upper magnet 9 is rigidly connected to the lower end of the E 4. The position of the MS 10 flexible cable is connected to the upper end of the magnet 8, and the adjacent ends of the magnets 8 and 9 have opposite poles. At the time of injection of cement mortar, E 4 is in the lower position and does not interfere with the circulation of fluid due to sediments between opposite poles of magnates.

8 and 9 and negative buoyancy of E 4 in the drilling fluid. When the ferromagnetic powder MS 10 is reached, the powder accumulates on MS 10, increasing its

 mass of Go down, MS 10 rotates 180 ° magnet 8. Between magnets 8 and

9 a repulsive force arises, and e 4 rises up due to positive buoyancy in the cement slurry. Sit back to planting seat 5, O 4 stops circulation. The increase in pressure indicates the end of the cementing process. 2 or

The invention relates to the mining industry, and more specifically to the oil and gas industry, and is used in the cementing of casing in the reverse way.

The purpose of the invention is to increase the reliability of receiving the signal about the end of cementing.

FIG. 1 shows a check valve at the time of injection of the solution; in fig. 2 shows the position of the valve parts after the end of the cementing process.

The check valve for casing cementing includes a hollow body 1 with ribs 2 placed on its inner surface, forming channels 3, a locking element 4 mounted for axial movement and having a positive buoyancy in the cement mortar, a seating saddle 5 for a locking element 4 and fairing b mounted in the lower part of the housing 1. The cowl 6 is made of a diamagnetic material and has a pop 7 in which the lower magnet 8 is rotatably mounted. The upper magnet 9 is rigidly connected to the lower end of the locking element 4. The magnetic rod 10 is placed under the fairing 6 and has the possibility of axial movement, and in the upper position of the magnetic rod 10 bending rod 11 is connected to the latter and the upper end of the lower magnet 8, and the adjacent ends of the lower 8 and upper 9 magnets have opposite poles.

The device works as follows.

In reverse cementing, the check valve is attached to the bottom of the casing, the column and lowered into the well. The circulating drilling fluid is restored. Since the density of the closure element 4 is greater than the density of the drilling fluid, it is in the lower position on the fairing 6. Due to the fact that

the upper 9 and lower 8 magnets face each other with opposite poles, the locking element 4 is firmly held in the lower position and the friction of the moving solution cannot lift it up.

After the preparatory work, the cement mortar is pumped into the core space, ferromagnetic powder 12 is added to the first portion. When the annular space is filled with cement mortar, its first portion flows into the casing and reaches the magnetic rod 10. Magnetic forces pull the ferromagnetic powder to themselves and it settles on magnetic

the rod 10. The weight of the magnetic rod 10 as a result of this increases and prevails over the attractive force of the magnets 8 and 9. Therefore, the lower magnet 8 rotates 180 ° on the axis and the magnetic rod J is shifted down. In this case, the lower magnet 8 faces the upper magnet 9 with the same pole. The locking element 4 is osboboda, repulsive force of the magnets 8 and 9, as well as the fact that the locking

element 4 has a positive buoyancy in cement mortar, contributes to the upward movement before landing on the saddle 5 (Fig. 2). Thus, the circulation system is closed, the pressure in it increases, which is a signal that the process of reverse cementing has ended.

Claims (1)

Claims Valve for Cementing casing strings, including a hollow body with ribs placed on its inner surface, forming circulation channels, a locking element mounted for axial displacement and having a positive buoyancy in the cement mortar, a seating seat for the locking element and a fairing mounted in the lower part of the body, differing By the fact that, in order to increase the reliability of receiving the signal about the end of cementing, it is equipped with an upper magnet rigidly connected to the lower end of the locking element the lower magnet, the magnetic rod and the flexible rod, while the fairing is made of a diamagnetic material and has a cavity in which the lower magnet is rotatably mounted, the magnetic rod is placed under the fairing and is axially displaceable. The flexible tube is connected to the latter and to the upper end of the lower magnet, and the adjacent ends of the upper and lower magnets have opposite poles,