Gas supply of Kurgan city district

Contents

Summary

Contents

Introduction

1 Design of external gas supply networks

1.1 Determination of geometric area

1.2 Determination of annual heat consumption

1.3 Determination of annual gas consumption

1.4 Determination of maximum hourly gas flow rate

1.5 Selection of optimal amount of GRPP

1.6 Selection of GRPP equipment

1.7 Hydraulic calculation of low pressure gas pipelines

2 Design of internal gas supply system

2.1 General characteristic of the gas supplied facility

2.2 Hydraulic calculation of internal gas pipeline

3 Technology and organization of installation works

3.1 Design of works for installation of external gas pipelines

4 Schedule

5.1 Calculation of cost-effectiveness of design solutions

5.2 Technical and Economic Indicators

6.1 Safety precautions during installation works

6.2 Excavation Safety

6.3 Safety precautions for gas pipeline installation and testing

6.4 Handling Safety

6.5 Safety precautions during operation of single bucket excavator

6.6 Safety precautions during bulldozer operation

6.7 Personnel Safety at Gas Pipeline Construction

6.8 Gas Pipeline Test Safety Precautions

6.9 Sanitary services for personnel

List of literature

Annotation.

This diploma project has developed a gas supply system for the Kurgan region. Gas extraction from the main gas pipeline is carried out through GRPP.

The gasified area is located in the city of Kurgan. The development of the district with multi-storey houses. The population density is 220 people/ha. A ring system has been adopted for gas supply of the district. The source is a high pressure gas pipeline. Based on the conditions of development, the laying of gas distribution gas pipelines is provided underground, along the carriageways of the streets in the zone of green spaces. To reduce pressure, a cabinet gas control station of GRPSH400 grade is provided, located in the residential quarter next to the connection point.

According to the task, the calculation and design of the gas supply system of a residential building was carried out. The residential building is equipped with a 4-block gas plate PG4. For accounting of a consumption of gas the SGBG4 gas meter, for ensuring emergency shutdown of supply of gas in case of fire the thermoshut-off valve is provided .

In the section of technology and organization of installation works, work projects for the installation of external and internal gas pipelines have been developed.

In the economic part, a consolidated estimate, object estimate and local estimates for the installation of external and internal gas pipelines were made.

In the section of engineering and technical solutions on life safety, methods of ensuring the safety of maintenance personnel during the construction of a gas pipeline are considered.

Introduction.

The degree project is the final stage of the educational process, which determines the level of training of a specialist. The nature of the diploma project is a complex task, which involves the systematization, consolidation and expansion of theoretical knowledge and practical skills obtained during the training period, linking theoretical knowledge with practice.

Since natural gas is a highly efficient energy carrier, in the context of an economic crisis, gasification can form the basis of the socio-economic development of the regions of Russia, ensure the improvement of working and living conditions of the population, as well as reduce environmental pollution.

The use of gas fuel makes it possible to introduce efficient methods of fuel transfer, create economical and high-performance thermal units with smaller dimensions, cost and high efficiency, as well as improve the quality of products.

The main tasks in the development of gas supply systems are:

1. Uninterrupted, reliable and safe supply of gas to consumers;

2. Rational use of gas with the introduction of fuel-efficient systems. Accounting and control of gas expenditures from the moment of production to the consumer;

3. Introduction of energy-saving technologies ;

4. Introduction of efficient gas-using equipment;

5. Application of new polymer materials, new pipe structures and connecting elements for networks and equipment;

6. Provision of natural gas-based heat and electricity for decentralized heat and energy supply to small towns and rural localities;

7. The purpose of the system development, improvement of technological schemes, introduction of new polymer materials for gas transportation, expansion of the use of gases as motor fuel, monitoring and diagnostics of the technological chain by gas of consumers.

Natural gas as a highly efficient energy carrier is now widely used in many parts of public production, has a direct impact on increasing industrial and agricultural output, increasing labor productivity and reducing specific fuel costs.

2.1.6 Instructions for performance of works.

2.1.6.1 Preparatory works.

The construction of gas pipelines begins after the installation organization receives the approved design and estimate documentation from the customer. From a specialized organization, obtain a diagram and an act for the geodetic work performed.

Permission to perform works with indication of the terms of works, position and name of the person responsible for works.

The initial stage of preparatory work is the marking performed by the representative of the production preparation area. The route is divided from the existing gas pipeline or GRP, from the red lines of the buildings. The breakdown consists in fixing on the ground the contours of the route with wooden rings or metal pins with a length of 400500 mm, a diameter of 1215 mm at the corresponding points.

Prior to the commencement of work, the general contractor calls representatives of the corresponding underground communications to the place, manually taps at the intersections, cables are closed and suspended. Preparatory work includes: power supply, lighting, provision of water supply, sewage, appliances, drinking water, bathrooms. In the case of construction of houses with gas supply, fences, speed limiters, fire extinguishing equipment, visors above the entrances for the width of the cargo fall are required.

2.1.6.2.Earthworks.

Construction work is most often carried out in-line with the breakdown of the gas pipeline into sections with grips. Length of sections is selected depending on presence of underground communications crossing the route, horizontal turns of road route and other obstacles depending on local conditions.

The length of the sections shall be equal to the actual length of the pipes and sections to avoid additional cutting and welding of the laid pipes. The depth of gas pipelines depends on the soil, on the humidity of the transported gas. The labor intensity of soil development depends on their density, connectivity, humidity, degree of looseness and other properties of soils.

The labour intensity of soil breakdown is given in ENiRE No. 2 issue 1. In soils of natural humidity in the absence of groundwater, digging of pits for wells and trenches with vertical walls without fastenings can be carried out to a depth of no more than: 1 m in sandy and gravelly soils, 1.25 m in sandy loams, 1.5 m in loam and clays, 2 m in especially dense rock soils.

Pits and trenches shall be protected from surface water runoff, by means of soil dumps and by devices of special drainage trays from pipes. The soil dump is placed at a minimum distance from the edge of the trench of 0.5 m. The bottom of the finished trench is leveled. The lack of soil is cleaned with shovels manually.

The base for the gas pipeline is filled with sandy soil with a thickness of at least 100 mm. In places of crossings and intersections with road surfaces, backfilling is performed with careful compaction of soil and watering with water. Above the trenches are arranged rollers from soil and watering with water. Above the trenches, rollers are arranged from the soil with the expectation of gradual shrinkage.

2.1.6.3. Requirements before assembly and welding of pipes.

Before assembly and welding, pipe ends and connection parts intended for butt welding are thoroughly cleaned and wiped inside and outside of all contaminants at a distance of at least 50 mm from pipe ends. Cleaning is carried out with dry or moistened towels (rags) with further wiping dry.

If the ends of the pipes or parts are contaminated with lubricating oil, or any other fats, they are degreased with alcohol, acetone. Parts with embedded electric heaters are removed from the package so that dust and dirt from the package does not get inside the part. Pipe ends of parts prepared for welding with ZN shall be checked to ensure that they are cut evenly. Ends of pipes deformed or having deep nicks more than 4-5 mm are trimmed. For Saddle branches, the place on the pipe where they will be installed is cleaned. The thickness of the stripped layer depends on the pipe diameter tolerance and should not result in unacceptable gaps between the pipe and the part.

2.1.6.4 Installation technology of gas pipelines and equipment.

After acceptance of the object for installation according to the act, the team undergoes safety training at the workplace. By the time of installation, all preparatory work was carried out. Pickets are put up at the intersection of the gas pipeline with other communications. Representatives of the relevant communications are called. Installation of the gas pipeline is performed on the eyebrow.

Before installation the conformity of equipment, materials, fittings, certificates and passport shall be checked.

They are stroked using soft towels and lowered into a trench using a pipe laying device. Gas pipeline is laid carefully on prepared bed. The correct laying of the gas pipeline is checked visually, and it is reduced to the absence of a section of incomplete abutment. Depth of laying, slope and distance between gas pipeline and communications are checked.

Skews in vertical and horizontal planes are not allowed.

For installation of reinforcement and compensators, carpets, concrete and brick wells are built by the general contractor. Installation of equipment and fittings is carried out as the gas pipeline is built and completed, the fittings are cleaned of dirt, sand, scale before installation.

When passing the gas pipeline through the road, the tram tracks the gas pipeline consists of a case. Inner diameter of case is 100 mm larger than outer gas pipeline. Case end is sealed with gland seal and has control tube introduced under carpet.

Correctness of gas pipeline laying is checked by leveling of all units. Cases and insulated flanges are provided at the places where the gas pipeline leaves the ground.

During installation of gas pipelines, measures must be taken to prevent clogging of the pipe cavity, sections, and lashes.

After laying the gas pipeline in the trench, the following should be checked: design depth, slope and abutment of the gas pipeline to the bottom of the trench throughout its length; state of gas pipeline protective coating; actual distances between the gas pipeline and the walls of the trench, the structures crossed by it and their correspondence to the design distances.

The correct laying of gas pipelines should be checked by leveling all corner points of the laid gas pipeline and its intersection with underground structures. If after gas pipeline laying

the presence of its loose abutment to the bottom of the trench in separate places will be established, then in their places soil should be filled with its layer-by-layer compaction and sinus picking.

During welding of shaped parts, assemblies, fittings and other devices into the gas pipeline, alignment of welded elements with the gas pipeline must be ensured. Skews in horizontal and vertical planes are not allowed.

2.1.6.5 Selection of optimal welding mode.

The desired welding parameters are selected depending on the welding method used. Depending on ambient air temperature, welding parameters are adjusted as required: time and temperature of heaters.

The main parameters when welding with a heated tool are the temperature of the heated tool and the value of pressure and time.

For machines with manual control, the technological parameter may be abnormal due to the complexity of its implementation. For automated machines, parameter values are usually entered into the memory unit of the control device or are read using a photo-optical pencil from a plastic card. As a rule, in this case, changes in parameters are either impossible, or can be made only after the automation unit reads the code from a special control card.

2.1.6.6 Testing of gas pipelines.

External and internal gas pipelines completed with construction or reconstruction should be tested for air tightness. For testing, the gas pipeline in accordance with the project of work should be divided into separate areas limited by plugs or closed by linear valves and shutoff devices in front of the gas-using equipment, taking into account the permissible pressure drop for this type of valves (devices).

If valves, equipment and instruments are not designed for test pressure, then coils, plugs shall be installed instead for the test period.

Gas pipelines of residential, public, domestic, administrative, industrial buildings and boiler houses should be tested in the area from the disconnecting device at the entrance to the building to the cranes of gas-using equipment.

Gas pipelines shall be tested by a construction and installation organization in the presence of a representative of the operational organization.

Test results shall be recorded in the construction certificate.

Prior to the leak test, the inside of the gas pipeline shall be cleaned in accordance with the work design. Cleaning of the cavity of internal gas pipelines and gas pipelines of FRG should be carried out before their installation by air blowing.

For tests of gas pipelines, pressure gauges of accuracy class 0.15 shall be used. It is allowed to use pressure gauges of accuracy class 0.40, as well as accuracy class 0.6. V-shaped liquid pressure gauges (water filled) shall be used at a test pressure of up to 0.01 MPa.

Underground gas pipelines should be tested for strength after their installation in a trench and filling 2025 cm above the upper generatrix of the pipe. Test pressure 0.6 MPa with exposure of not less than 1 hour. The results of the strength test should be considered positive if the pressure in the gas line does not change during the test period (there is no visible pressure drop on the pressure gauge). Underground gas pipelines should be tested for tightness after full backfilling of the trench to design elevations. Before the start of tightness tests underground gas pipelines after their filling with air should be held under test pressure of at least 6 hours, test pressure of 0.01 MPa with exposure of at least 24 hours. The result of the leak test should be considered positive if during the test the actual pressure drop in the gas pipeline does not exceed the permissible pressure drop and no leakage is detected during the inspection of the places available for inspection.

Defects found during tests of gas pipelines should be eliminated only after the pressure in the gas pipeline is reduced to atmospheric.

After elimination of defects detected as a result of the gas pipeline leak test, the test shall be repeated.

Gas pipeline joints welded after testing shall be checked by physical inspection.

2.1.6.7 Commissioning of facilities.

The completed object is handed over to the acceptance commission. It includes: customer, representative of the general contractor, operating organization, representative of Rosgortekhnadzor R.F., representative of the project organization. The General Contractor for the gas supply system facility shall submit the following as-built documentation to the acceptance commission in the 1st copy:

1) set of working drawings with all approvals and changes;

2) certificates of manufacturers for pipes, shaped parts, welding and insulation materials;

3) technical passports of manufacturers for equipment, coating, insulating flanges, fittings (over 100 mm), instructions of manufacturers for the operation of equipment and devices;

4) construction passport of the gas pipeline and the report of inspection of quality of welded joints and testing of gas pipelines;

5) act of route breakdown and transfer;

6) act of acceptance of installations, hidden and special works;

7) act of acceptance of electrochemical protection plants;

8) work log.