Places for installing bales on the gas pipeline. Instrumentation. Diagram of a self-recording pressure gauge with a multi-turn spring

What do you need to prepare?

• laying and backfilling of the pipeline;
• fixing marks in places where instrumentation is installed:
• connecting cables to the pipeline, securing electrochemical potential sensors.

• at the first stage, persons are appointed who are responsible for the high-quality and safe performance of upcoming tasks:
• the necessary permits are requested to carry out the work;
• Team members are introduced to the technology used and given safety training.

What does the work include?

TYPICAL TECHNOLOGICAL CARD (TTK)

INSTALLATION OF CONTROL AND MEASUREMENT POINTS DURING CONSTRUCTION
MEANS OF ELECTROCHEMICAL PROTECTION OF GAS PIPELINE

I. SCOPE OF APPLICATION

I. SCOPE OF APPLICATION

1.1. A standard technological map (hereinafter referred to as TTK) is a comprehensive regulatory document that establishes, according to a specific technology, the organization of work processes for the construction of a structure using the most modern means mechanization, progressive designs and methods of performing work. They are designed for some average operating conditions. The TTK is intended for use in the development of Work Projects (WPP), other organizational and technological documentation, as well as for the purpose of familiarizing (training) workers and engineers with the rules for carrying out work on the installation of Control and Measuring Points (hereinafter referred to as instrumentation).

1.2. This map provides instructions on the organization and technology of work on the installation of control and measuring points, rational means of mechanization, provides data on quality control and acceptance of work, requirements industrial safety and labor protection during work.

1.3. The regulatory framework for the development of technological maps is: SNiP, SN, SP, GESN-2001 ENiR, production standards material consumption, local progressive norms and prices, labor cost norms, material and technical resource consumption norms.

1.4. The purpose of creating the TC is to describe solutions for the organization and technology of work on the installation of instrumentation in order to ensure their High Quality, and:

- reducing the cost of work;

- reduction of construction duration;

- ensuring the safety of work performed;

- organizing rhythmic work;

- unification of technological solutions.

1.5. On the basis of the TTK, as part of the PPR (as mandatory components of the Work Project), Workers are being developed technological maps(RTK) for execution individual species works Working technological maps are developed on the basis of standard maps for the specific conditions of a given construction organization, taking into account its design materials, natural conditions, the available fleet of machines and building materials tied to local conditions. Working technological maps regulate technological support means and implementation rules technological processes during the execution of work. Design features for the installation of instrumentation are decided in each specific case by the Working Design. The composition and degree of detail of materials developed in the RTC are established by the relevant contracting authority construction organization, based on the specifics and volume of work performed. Working flow charts are reviewed and approved as part of the PPR by the head of the General Contracting Construction Organization, in agreement with the Customer's organization, the Customer's Technical Supervision.

1.6. The technological map is intended for work manufacturers, foremen and foremen who carry out work on the installation of instrumentation during the construction of electrochemical protection of a gas pipeline, as well as technical supervision workers of the Customer and is designed for the specific conditions of work in the third temperature zone.

II. GENERAL PROVISIONS

2.1. The technological map has been developed for a set of works on installation of instrumentation.

2.2. Work on installation of instrumentation is carried out in one shift, the duration of working hours during a shift is:

Where 0.828 is the coefficient of use of mechanisms over time during a shift (time associated with preparation for work and carrying out technical maintenance - 15 minutes, breaks associated with the organization and technology of the production process and driver rest - 10 minutes every hour of work).

2.3. The technological map provides for the work to be carried out by a complex mechanized unit using an EO-2621 single-bucket excavator with a bucket capacity of 0.25 m (see Fig. 1).

Fig.1. Single-bucket excavator EO-2621

2.4. Instrumentation installation work includes:

- geodetic breakdown of the location;

- digging a pit;

- connection of cathode and control leads to the pipeline;

- installation of reference electrodes;

- backfilling the pit;

- installation of instrumentation;

- connection of cables, reference electrode wires.

2.5. The control point is a column made of polymer material, having the shape of a trihedron, 2500 mm long with a mounting shield protected from dust and moisture. The number of instrumentation, their brand and location along the gas pipeline route are determined by the Detailed Design. Current measuring and marker points are combined with stationary instrumentation.

2.6. Current measuring control points are installed on average every 5.0 km, as well as on both sides of the case when crossing roads and railways. The following are connected to the mounting panel of the current measuring control point:

- cable from long-term reference electrodes;

- cable from electrochemical potential sensors (auxiliary electrode) and corrosion rate sensors;

- measuring cable from the pipeline (cathode terminal);

- current measuring cables welded to the gas pipeline at a distance of 30.0 m from the point.

2.7. Marker points are designed to link data from planned in-line flaw detection and are installed every 2.0-3.0 km along the gas pipeline route. The mounting panel of such an instrumentation is connected to cables welded to the gas pipeline at the installation site of the instrumentation and directly to marker pads installed in pairs 5.0 m from the instrumentation.

2.8. Work should be carried out in accordance with the requirements of the following regulatory documents.

Description Characteristics Installation

Control and measuring points PVEK and LEADER are used to monitor ECP parameters, switch measuring and power circuits and to mark the routes of metal pipelines and other underground communications, metal structures.

Features of PVEC instrumentation

Structurally, the PVEK body is a three- or tetrahedral rack made of plastic that is resistant to combustion and atmospheric exposure. Information markings are applied to the item on the outside.

The instrumentation itself is manufactured white. Shades individual elements points depend on the type of pipeline being monitored. The signal cap installed on the top of the device for production pipelines is blue, for main pipelines- yellow, for underground storage pipelines - green, and the control and measuring point on the gas pipeline (on gas distribution pipelines) has a red cap.

Instruments are produced four types. Type 1 is installed on the linear part of pipelines, type 2 - on the linear part of pipelines and on industrial sites, type 2B “winchester” with retractable top part- at industrial sites, type 3 - directly to the pipeline.

To expand the capabilities of the PVEK instrumentation racks, they can be supplemented with joint protection units BSZ, protective-grounding devices UZZ, devices for protecting electrical insulating inserts UZ, gas leakage monitoring devices UKG, switching devices UK, monitoring devices for anode grounding conductors, electrical jumpers and protectors KAZ-M, control units and regulation of currents of anode grounding conductors RKT, corrosion monitoring units BKM. They can also be supplemented with kilometer signs PVEK-1 (for racks of type 1), PVEK-2 (for racks of types 2, 2B, 3) and other options.

KIP LEADER

KIP LEADER - equipment own production EKhZ-Center company. A device enclosed in a housing made of non-flammable and protected from atmospheric influences plastic, installed on industrial sites, on pipelines directly and on the linear part of pipelines. KIP LEADER is supplemented with switching devices, for monitoring gas leaks, joint protection units and other equipment to expand its functionality.

The control and measuring stations PVEK and LEADER offered by the EKhZ-Center company are universal products that are used not only as measuring devices with terminal sets, but also as unified, intelligent and multifunctional products with a modern aesthetic appearance.

PVEK control and measuring points are designed for switching power and measuring circuits of electrochemical protection equipment and monitoring ECP parameters. KIP PVEK is a 3- or 4-sided rack made of weather-resistant non-flammable plastic, with information marking applied on the outside; depending on the type of design, the KIP PVEK rack can be additionally equipped with BSZ blocks (joint protection unit) and PVEK-1 kilometer signs, PVEK-2.

KIP PVEK with BSZ (Joint Protection Unit)

Instrumentation control points PVEK with BSZ are designed to regulate the current in magnitude and direction, while increasing the harmful mutual influence of neighboring communications, electrochemical protection of underground metal structures together with the station cathodic protection, also intended for marking pipeline routes and other metal underground structures and communications.

PVEK KIPs are manufactured in white color. The colors of other instrumentation elements, depending on the type of pipeline, correspond to the table.

Construction, installation and commissioning of all types of electrochemical protection equipment. Specialists from two mobile teams of the company perform full complex construction, installation and commissioning works. Commissioning of electrochemical protection facilities, installation cable lines and device utility networks Full construction.

Construction of ECP, installation of drainage protection installations, sacrificial protection, extended (elastomer) electrodes of the ELER type and more.

Properly installed cathodic and sacrificial protection can significantly (several times) increase the service life of the pipeline.

If you have working documentation (project), you can attach the file to your application.

In hydraulic fracturing, the following instrumentation is used to monitor the operation of equipment and measure gas parameters:

• thermometers for measuring gas temperature;
• indicating and recording (self-recording) pressure gauges for measuring gas pressure;
• instruments for recording pressure drop on high-speed flow meters;
• Gas consumption metering devices (gas meters or flow meters).

All instrumentation must be subject to state or departmental periodic verification and be constantly ready to take measurements. Readiness is ensured by metrological supervision. Metrological supervision consists of constantly monitoring the condition, operating conditions and correctness of instrument readings, periodically checking them, and removing from service devices that have become unusable and have not passed the test. The instrumentation must be installed directly at the measuring point or on a special instrument panel. If the instrumentation is mounted on the instrument panel, then one device with switches is used to take readings at several points.

Instrumentation is connected to gas pipelines steel pipes. Impulse tubes are connected by welding or threaded couplings. All instrumentation must have marks or seals of Rosstandart authorities.

Instrumentation with an electric drive, as well as telephone sets, must be explosion-proof, otherwise they are placed in a room isolated from the gas distribution center.

The most common types of instrumentation in hydraulic fracturing include the devices discussed later in this section.

Instruments for measuring gas pressure are divided into:

• for liquid devices in which the measured pressure is determined by the value of the balancing liquid column;
• spring devices in which the measured pressure is determined by the amount of deformation of the elastic elements ( tubular springs, bellows, membranes).

Liquid pressure gauges are used to measure excess pressures in the range of up to 0.1 MPa. For pressures up to 10 MPa, pressure gauges are filled with water or kerosene (at negative temperatures), and when measuring higher pressures - with mercury. TO liquid pressure gauges This also includes differential pressure gauges (differential pressure gauges). They are used to measure pressure drop.

Differential pressure gauge DT-50(picture below), Thick-walled glass tubes are firmly fixed in the upper and lower steel blocks. At the top, the tubes are connected to trap chambers, which protect the tubes from the release of mercury if the maximum pressure increases. There are also needle valves with which you can disconnect glass tubes from the medium being measured, purge connecting lines, and also turn the differential pressure gauge off and on. Between the tubes there is a measuring scale and two indicators that can be installed on the upper and lower levels of mercury in the tubes.

Differential pressure gauge DT-50

a - design; b - channel layout diagram; 1 - valves high pressure; 2, 6 - pads; 3 - camera traps; 4 - measuring scale; 5 - glass tubes; 7 - pointer

Differential pressure gauges can also be used as conventional pressure gauges for measuring excess gas pressures, if one tube is vented into the atmosphere and the other into the medium being measured.

Pressure gauge with single-turn tubular spring(picture below). A curved hollow tube is fixed with its lower fixed end to a fitting, with the help of which the pressure gauge is connected to the gas pipeline. The second end of the tube is sealed and pivotally connected to the rod. The gas pressure is transmitted through the fitting to the tube, the free end of which causes movement of the sector, gear and axle through a rod. The spring hair ensures the adhesion of the gear and sector and the smooth movement of the arrow. A shut-off valve is installed in front of the pressure gauge, allowing, if necessary, to remove the pressure gauge and replace it. During operation, pressure gauges must pass state verification once a year. Operating pressure, measured by a pressure gauge, should be in the range from 1/3 to 2/3 of their scale.

Pressure gauge with single-turn tubular spring

1 - scale; 2 - arrow; 3 - axis; 4 - gear; 5 - sector; 6 - tube; 7 - traction; 8 - spring hair; 9 - fitting

Recording pressure gauge with a multi-turn spring (figure below). The spring is made in the form of a flattened circle with a diameter of 30 mm with six turns. Due to the large length of the spring, its free end can move by 15 mm (for single-turn pressure gauges - only by 5-7 mm), the angle of unwinding of the spring reaches 50-60°. This design allows the use of simple lever transmission mechanisms and automatic recording of readings with remote transmission. When a pressure gauge is connected to the medium being measured, the free end of the lever spring will rotate the axis, and the movement of the levers and rods will be transmitted to the axis. A bridge is attached to the axis, which is connected to the arrow. The change in pressure and the movement of the spring are transmitted through the lever mechanism to a pointer, at the end of which a pen is installed to record the measured pressure value. The diagram rotates using a clock mechanism.

Diagram of a self-recording pressure gauge with a multi-turn spring

1 - multi-turn spring; 2, 4, 7 - levers; 3, 6 - axes; 5 - traction; 8 - bridge; 9 - arrow with feather; 10 - cartogram

Float differential pressure gauges.

Float differential pressure gauges (figure below) and restriction devices are widely used in the gas industry. Constriction devices (diaphragms) are used to create a pressure difference. They work in conjunction with differential pressure gauges that measure the pressure difference created. At steady gas flow total energy gas flow consists of potential energy (static pressure) and kinetic energy, that is, speed energy.

Before the diaphragm, the gas flow has an initial speed of ν 1 in a narrow section; this speed increases to ν 2; after passing through the diaphragm, the tray expands and gradually restores its previous speed.

As the flow speed increases, its kinetic energy and decreases accordingly potential energy, that is, static pressure.

Due to the pressure difference Δp = p st1 - p st2, the mercury located in the differential pressure gauge moves from the float chamber to the glass. As a result, the float located in the float chamber lowers and moves the axis to which the arrows of the device indicating gas flow are connected. Thus, the pressure drop across the throttling device, measured using a differential pressure gauge, can serve as a measure of gas flow.

Float differential pressure gauge

A - design diagram; b - kinematic diagram; c - graph of changes in gas parameters; 1 - float; 2 - shut-off valves; 3 - diaphragm; 4 - glass; 5 - float chamber; 6 - axis; 7 - impulse tubes; 8 - annular chamber; 9 - pointer scale; 10 - axes; 11 - levers; 12 - pen bridge; 13 - feather; 14 - diagram; 15 - hour mechanism; 16 - arrow

The relationship between pressure drop and gas flow is expressed by the formula

where V is the volume of gas, m 3; Δp - pressure drop, Pa; K is a coefficient that is constant for a given aperture.

The value of the coefficient K depends on the ratio of the diameters of the diaphragm opening and the gas pipeline, the density and viscosity of the gas.

When installed in a gas pipeline, the center of the diaphragm hole must coincide with the center of the gas pipeline. The diaphragm hole on the gas inlet side is cylindrical in shape with a conical expansion towards the flow outlet. The diameter of the disk inlet is determined by calculation. The entry edge of the disk hole must be sharp.

Normal diaphragms can be used for gas pipelines with a diameter from 50 to 1200 mm, subject to 0.05< m < 0,7. Тогда m = d 2 /D 2 где m - отношение площади отверстия диафрагмы к поперечному сечению газопровода; d и D - диаметры отверстия диафрагмы и газопровода.

Normal diaphragms can be of two types: chamber and disk. To select more precise pressure pulses, a diaphragm is placed between the annular chambers.

The positive vessel is connected to the impulse tube, which takes pressure to the diaphragm; The pressure taken after the diaphragm is supplied to the minus vessel.

In the presence of gas flow and pressure drop, part of the mercury from the chamber is squeezed into the glass (figure above). This causes the float to move and, accordingly, the arrow indicating the gas flow rate and the pen marking the pressure drop on the diagram. The diagram is driven by a clock mechanism and makes one revolution per day. The chart scale, divided into 24 parts, allows you to determine the gas consumption for 1 hour. A safety valve is placed under the float, which separates vessels 4 and 5 in the event of sharp drop pressure and thereby prevents the sudden release of mercury from the device.

The vessels communicate with the impulse tubes of the diaphragm through shut-off valves and an equalizing valve, which must be closed in the operating position.

Bellows differential pressure gauges(picture below) are designed for continuous measurement of gas flow. The operation of the device is based on the principle of balancing the pressure drop by the elastic deformation forces of two bellows, a torque tube and screw coil springs. The springs are replaceable, they are installed depending on the measured pressure difference. The main parts of the differential pressure gauge are the bellows block and the indicating part.

Schematic diagram of a bellows differential pressure gauge

1 - bellows block; 2 - positive bellows; 3 - lever; 4 - axis; 5 - throttle; 6 - negative bellows; 7 - replaceable springs; 8 - rod

The bellows block consists of interconnected bellows, the internal cavities of which are filled with liquid. The liquid consists of 67% water and 33% glycerin. The bellows are connected to each other by a rod 8. An impulse is supplied to bellows 2 before the diaphragm, and to bellows 6 - after the diaphragm.

Under the influence of higher pressure, the left bellows is compressed, as a result of which the liquid contained in it flows through the throttle into the right bellows. The rod, rigidly connecting the bottoms of the bellows, moves to the right and, through a lever, rotates the axis, kinematically connected to the arrow and pen of the recording and indicating device.

The throttle regulates the speed of fluid flow and thereby reduces the effect of pressure pulsation on the operation of the device.

For the corresponding measuring limit, replaceable springs are used.

Gas meters. Rotary or turbine meters can be used as meters.

Due to mass gasification industrial enterprises and boiler houses, increasing types of equipment arose the need for measuring instruments with a big throughput and a significant measurement range at small overall dimensions. These conditions are best met by rotary meters, in which 8-shaped rotors are used as a converting element.

Volumetric measurement in these meters is carried out due to the rotation of two rotors due to the difference in gas pressure at the inlet and outlet. The pressure drop in the meter required for rotation of the rotors is up to 300 Pa, which allows the use of these meters even at low pressure. The domestic industry produces meters RG-40-1, RG-100-1, RG-250-1, RG-400-1, RG-600-1 and RG-1000-1 for nominal gas flow rates from 40 to 1000 m 3 / h and pressure no more than 0.1 MPa (in SI units, flow rate is 1 m 3 / h = 2.78 * 10 -4 m 3 / s). If necessary, parallel installation of meters can be used.

Rotary counter RG(picture below) consists of a housing, two profiled rotors, a gearbox, a gearbox, an account mechanism and differential pressure gauge. Gas enters the working chamber through the inlet pipe. In the space of the working chamber there are rotors, which are driven into rotation under the influence of the pressure of the flowing gas.

Scheme of a rotary counter of the RG type

1 - meter body; 2 - rotors; 3 - differential pressure gauge; 4 - indicator of the counting mechanism

When the rotors rotate, a closed space is formed between one of them and the chamber wall, which is filled with gas. Rotating, the rotor pushes gas into the gas pipeline. Each rotation of the rotor is transmitted through a gearbox and gearbox to the counting mechanism. This takes into account the amount of gas passing through the meter.

The rotor is prepared for operation as follows:

• remove the upper and lower flanges, then wash the rotors with a soft brush dipped in gasoline, turning them with a wooden stick so as not to damage the polished surface;
• then wash both gearboxes and the gearbox. To do this, pour gasoline (through the upper plug), turn the rotors several times and drain the gasoline through the lower plug;
• Having finished washing, pour oil into the gear boxes, gearbox and counting mechanism, pour the appropriate liquid into the meter pressure gauge, connect the flanges and check the meter by passing gas through it, after which the pressure drop is measured;
• Next, listen to the operation of the rotors (they should rotate silently) and check the operation of the counting mechanism.

At technical inspection monitor the oil level in the gear boxes, gearbox and counting mechanism, measure the pressure drop, and check the tightness of the connections of the meters. Meters are installed on vertical sections of gas pipelines so that the gas flow is directed through them from top to bottom.

Turbine meters.

In these meters, the turbine wheel is driven into rotation by the gas flow; the number of wheel revolutions is directly proportional to the flowing volume of gas. In this case, the speed of the turbine is transmitted through a reduction gearbox and a magnetic coupling to a counting mechanism located outside the gas cavity, which shows the total volume of gas that has passed through the device under operating conditions.

main gas pipelines and other objects

"Gazprom"

Purpose

Control and measuring points RegionStroyZakaz (KIP.RSZ) For main gas pipelines and other facilities of OJSC Gazprom, depending on the configuration, are intended for monitoring and adjusting the parameters of electrochemical protection (ECP) of underground communications, switching individual elements of ECP systems, marking gas pipeline routes and other metal underground structures and cable communications. This type of product is personalized by applying the company logo and painting the body and individual parts of the item in colors that comply with the internal regulations of OAO Gazprom. Upon request, KIP.RSZ can be equipped with a high-altitude viewing roof (HVR) with kilometer or other markings.

KIP.RSZ are installed along the route of underground communications:

on straight sections within visibility, but at least every 500 - 1000 m (depending on the corrosion hazard of the underground communications section);

in places where the route of underground communications turns;

on both sides of the intersections of the underground communications route with artificial and natural barriers (roads, rivers, etc.);

in places where the drainage cable is connected to underground utilities;

in places where insulating flange connections are installed;

at intersections with routes of other overhead and underground communications.

Description:

KIP.RSZ is a product based on a round, triangular or triangular polymer profile square section with edge sizes from 130 to 200mm or diameters from 100 to 200mm, white, yellow, orange or other colors. Inside the instrumentation there is a terminal panel with terminals made of non-ferrous metal or corrosion-resistant steel for connecting power and measuring equipment. The terminal block is protected by a cover with a lock to prevent easy access. KIP.RSZ is equipped with an upper polymer cap, the color of which can vary depending on the type of communications being marked or other tasks. Reflective or fluorescent marks can be applied to both the sign itself and the colored cap. At the bottom of the product there is a device that prevents the free removal of instrumentation from the ground.

The control panel is located at the top of the rack and is closed with a lid with a lock. Inside the control panel there is a terminal panel with power and measuring terminals for switching ECP equipment and connecting measuring equipment. KIP.RSZ terminals, contact clamps and measuring sockets are made of non-ferrous metal or corrosion-resistant steel. The design of the clamps ensures reliable electrical fastening of cables and wires without special termination of cores:

for measuring clamps - with a cross section of up to 10 mm2;

for power clamps - cross-section up to 35 mm2.

Additional equipment for installation in KIP.RSZ

Additional equipment for KIP.RSZ

To expand the functionality, instrumentation systems can be equipped with the following devices:

Joint protection block(BSZ.RSZ) - designed for organizing joint electrochemicalprotection of two or more underground structures located in close proximity to each other (intersecting or parallel branches of underground communications) and elimination harmful influence neighboring communications by regulating protective current structures.

BSZ.RSZ can be supplied in various modifications, differing in the methods of regulating the protective current: resistor (BSZ-R.RSZ) and electronic (BSZ-E.RSZ) and the number of control channels from 1 to 4.

Block protective grounding (BZZ.RSZ) - designed to protect underground structures from the corrosive influence of electromagnetic fields of power lines located nearby and/or crossing the protected structure, as well as to organize lightning protection.

BZZ.RSZ can be supplied in modifications for protection against the influence of power lines (BZZ-L.RSZ) and for lightning protection

(BZZ-G.RSZ).ъ

Anode grounding control unit(BKAZ.RSZ) - designed for switching and monitoring the performance of anode grounding conductors and electrical connections by including a block in electrical circuits anode grounding conductors.

High-rise roof(KVO.RSZ) - designed to provide visual remote control of pipeline routes or communications from a height, during their inspection from an aircraft. Provides good visibility of signs with KVO, viewing and/or recording of serial numbers of kilometers or other information.

The high-rise roof is made of impact-resistant polystyrene in white, orange or red and is mechanically attached to the head of the identification and warning sign or control point. By agreement with the customer on top part KVO can be printed with kilometer marks or other information using screen printing or stickers.