RU2511787C1 - Marker for in-line inspection - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: marker consists of two marking straps made of ferromagnetic material and namely of pre-magnetised compound material with high plasticity properties; the straps are installed on top of a pipeline at a certain gap between them. The marker contains marks with reference index. The straps are fixed due to magnet forces interaction between the strap and steel pipe and the mark with reference index is placed to the ground when the pipeline is covered by earth.

EFFECT: reducing weight of the marker and labour intensity of its installation, improving mounting quality and reliability of its operation.

Description

The invention relates to magnetic in-line diagnostics and can find application in the oil and gas industry in determining the coordinates of metal defects in pipes of underground pipelines.

A device for signaling the passage through a pipeline of a magnetically carrying inspection shell, consisting of a remote sensor of a magnetic field and a signal conditioning amplifier (patent No. 2321027).

The disadvantages of the method include the technical complexity of the device and the need to provide the device with a source of electrical energy, which is difficult to implement, for example, when it is installed on the linear part of the main gas and oil pipelines.

Closest to the claimed invention is a marker consisting of two fragments of a steel pipe (linings), similar to those of which the pipeline is made and milestones with an information pointer welded to one of the linings and facing the day surface. Pads are installed on the upper generatrix of the pipeline with a distance between them of the order of 100-110 mm. The lining is mounted on the pipe with the help of insulating materials - heat-shrinkable cuffs or adhesive polymer tapes. The marker is usually installed at a distance of no more than 10 m from the control column of the electrochemical protection system in the direction of the product (Instructions for the manufacture and installation of marker pads SPE 1.010.00.00-10.09 I (Revision 2) - CJSC NPO Spetsneftegaz , CJSC NPO Spektr, Ekaterinburg, 2006).

The disadvantages of the known technical solutions include:

- large mass (mass of two linings for the pipeline 1420 mm about 60 kg) and metal consumption;

- the need to manufacture linings for a specific diameter of the pipeline and the technical complexity of the manufacture of linings for pipes of non-standard diameter;

- the need for fastening and corrosion protection of the linings;

- high complexity and, as a result, the cost of installing the marker, due to the need for a full-profile opening of the pipe for fixing the lining with insulating materials;

- the risk of damage (punching) by the edges of the lining of the insulating coating of the pipeline due to a mismatch of the inner radius of the lining and the outer radius of the pipeline taking into account the insulating coating, as a result, the risk of corrosion of the pipe metal.

- the risk of damage to the milestones during mechanized backfilling of the pipeline section.

The technical task to be solved is the creation of a marker for in-line diagnostics, which allows to reduce the complexity and improve the quality of its installation, preventing displacement from the initial installation without additional mounting means, as well as reducing the weight of the marker.

Achievable technical result of the invention is to reduce the mass of the marker, reducing the complexity and improving the quality of installation of the marker.

The problem is solved in that in the marker for in-line diagnostics, consisting of at least two marker pads made of ferromagnetic material, installed on the top of the pipeline with a certain distance between them, milestones with an information pointer facing the day surface, the pads are of pre-magnetized composite material with high plastic properties, digging out the pipeline is carried out only to its top, while the lining is fixed due to the strength of the magnet deleterious interaction between the lining and the steel pipe, and the landmark information with a pointer having the bottom of the device that prevents its pulling out of the soil, set into the ground when backfilling pipeline.

As an explanation, we give the following:

The use for the manufacture of linings from corrosion-resistant composite plastic materials with magnetic properties allows to reduce weight and size indicators compared to linings made from fragments of steel pipes, in addition, eliminates the need for passive protection against corrosion and minimizes the risk of damage to the pipe insulation by the liner.

The force of attraction of the magnetic plates to the steel pipe prevents the plates from moving from the initial installation without additional fasteners, which allows you to dig out the pipe only until the top of the pipe is released and minimize the cost of installation, fastening and insulation of the plates.

The high plastic properties of marker linings made of composite materials allow the use of the same linings to create markers on pipelines of various diameters.

Fastening a milestone with an information indicator directly to the ground during backfilling of the pipeline eliminates the risk of damage to the milestone and possible slip of the lining.

Example

On the section of the main gas pipeline with a coordinate of 102.351 km made of steel pipes with a diameter of 1420 mm and a wall thickness of 17 mm, it is necessary to install marker No. 9 (M9) for in-line diagnostics in order to subsequently bind defective places on the pipeline. The depth of the pipeline to the upper generatrix of 0.9 m.

At the gas pipeline section, manually dig out the soil to the upper generatrix of the pipe. They clean the insulation surface of the gas pipeline from soil particles. Manually lower the pads of a corrosion-resistant magnetoplast made of rubber with magnetic filler — anisotropic NdFeB-8A powder — into the pit. The dimensions of the pads are 350 × 350 × 10 mm. The weight of each pad is about 6 kg. Lay the pads on the upper generatrix of the pipeline, while providing a distance between the pads of 100 mm. Due to the strength of the magnetic interaction of the magnetoplast and the wall of the steel pipe, the pads fit snugly to the pipe and repeat its shape. Sprinkle pads with soil. A milestone made of a polypropylene pipe with a diameter of 20 mm and a wall thickness of 3 mm is installed on the ground above the pads. In the lower part, the pole has a polymer disk with a diameter of 200 mm and a thickness of 20 mm, fixed in such a way that the axis of the pipe coincides with the axis of the disk. Perform the final filling of the site. On the milestone put the marker pointer "M9".

Claims (1)

Marker for in-line diagnostics, consisting of at least two marker pads made of ferromagnetic material installed on the top of the pipeline with a certain distance between them, milestones with an information pointer facing the day surface, characterized in that the pads are made of pre-magnetized composite material with high plastic properties, digging out the pipeline is carried out only to its top, while the lining is fixed due to the strength of the magnetic interaction tions between the plate and steel pipe, and the landmark information with a pointer having the bottom of the device that prevents its pulling out of the soil, set into the ground when backfilling pipeline.