Air collector made of seamless steel pipes. Technical characteristics of air collectors

Device volume: from 0.5 to 100 cubic meters

Working pressure, MPa: up to 16 MPa.

Temperature working environment: –60 to +180 °С

Types of devices: horizontal, vertical

Industrial, chemical and many other enterprises often use equipment powered by air supply, which is also used for cooling. In order to collect air for further distribution, receivers are installed air collectors , in which a certain amount of air accumulates. They are also used to equalize pressure in systems, which eliminates the occurrence of pulsations. The applications of these devices are very diverse.

TYPES OF AIR COLLECTORS

All air collectors existing today can be divided into vertical and horizontal. Each type is selected depending on which location on the site is more convenient. Vertical devices are used in places with limited space, where it is not possible to mount a horizontal installation. For each type of air collectors, a certain foundation is laid, the parameters of which are prescribed in the documentation that comes with the installation. Devices differ in volume and operating pressure. Based on these parameters, they are selected at the time of purchase.

PURPOSE OF AIR COLLECTORS

The main purpose of such devices is to provide the necessary amount of air to stationary compressors, equalize pressure in air ducts and other tasks where air supply is required. These devices are found in automobile workshops, factories and various enterprises.

Air collectors, in addition to the container in which the air is collected, are equipped with a safety valve, pressure gauge, tap and, possibly, some other elements. The cost of such installations can be very varied and depends on the volume, operating pressure, type, equipment and other parameters.

The containers from which air collectors are made also allow storing various gases, such as nitrogen, argon and others. The quality of the containers is always at the highest level, so they are used in the harshest conditions.

Technical characteristics of air collectors

Materials used for the production of air receivers and pressure vessels should maintain their reliable operation during the design service life, taking into account the specified service conditions (maximum design temperature, design pressure and minimum negative), the nature and composition of the environment (toxicity, corrosiveness, explosion hazard etc.) and the influence of ambient temperature.

For the repair, production and installation of air receivers and pressure vessels and their parts, the basic materials listed in Appendix 4 to regulatory documentation receivers.

The use of materials listed in Appendix 4 for the production of air receivers and pressure vessels and their components used to work with parameters beyond the established limits or not listed in Appendix 4, as well as in accordance with other standards and specifications, is permitted by approval Gosgortekhnadzor of the Russian Federation, provided that the properties and quality of the materials are not lower than those regulated by the standard and specifications, and the presence of a positive conclusion from a specialized organization in the structure of pressure vessels, welding and metal science.

Copies of permits must be attached to the documentation for the receiver or pressure vessel.

The use of clad and surfacing materials is permitted for the production of air receivers and pressure vessels if the materials of the main and cladding layers are listed in Appendix 4, and the surfacing materials are listed in the specifications agreed with a specialized institute.

When selecting materials for air receivers and pressure vessels used for work on open area or in unheated rooms, the absolute minimum outdoor air temperature for a given region should be taken into account.

The properties and quality of materials and semi-finished products should meet the requirements of the relevant specifications and standards, as well as be confirmed by supplier certificates. If the certificate or marking is incomplete or missing, the vessel manufacturer (repair and installation organization) must carry out all necessary checks and document the results with a protocol that replaces or supplements the certificate of the material supplier. The certificate must specify the method of heat treatment of the semi-finished product at the manufacturer.

The scope and methods of testing materials should be regulated on the basis of standards and specifications determined in the established manner.

Filler materials used in the production of air receivers and pressure vessels and their parts should meet the requirements of the relevant specifications or standards.

The use of filler materials of certain brands, as well as fluxes and shielding gases, must be carried out in accordance with the specifications for the manufacture of this air receiver or pressure vessel and welding instructions.

The use of new filler materials, fluxes and shielding gases is allowed by the management of the enterprise after confirming their manufacturability when welding an air receiver, checking the entire complex of required properties of welds (including metal properties welded joint) and a positive conclusion from a specialized welding institute.

The use of electric welded pipes with a spiral or longitudinal seam is permitted in accordance with specifications or standards approved by a specialized institute, provided that the entire length of the weld is checked by ultrasound, radiography or other similar flaw detection.

Each welded or seamless pipe must undergo hydraulic testing. The value of such test pressure during a hydraulic test must be specified in the RD for such pipes. It is permitted not to carry out hydraulic testing of seamless pipes if they are controlled over the entire surface by physical methods (ultrasonic, radiographic, or other similar method).

Forgings with surfacing, deposited or clad sheets should undergo ultrasonic testing or control by other methods, which make it possible to detect detachments of the deposited (cladding) layer from the main layer of metal, as well as delaminations and discontinuities in the metal of forgings. In this case, quality assessment criteria are established by standards or specifications for clad or deposited sheets and forgings, agreed upon with specialized institutes. Bimetallic sheets with a thickness of more than 2.5 cm, used for the production of air receivers and pressure vessels operating under pressure over 40 kgf/cm2 (4.0 MPa), should undergo full control by ultrasonic flaw detection or other similar methods.

Low-alloy and carbon sheet steel with a thickness of more than 6 cm, used for the production of air receivers and pressure vessels operating under pressure over 100 kgf/cm2 (10.0 MPa), must undergo inspection of each sheet by ultrasonic or other similar flaw detection method.

Forgings made of low-alloy, carbon and alloy steels, used for work under pressure over 63 kgf/cm2 (6.3 MPa) and having one of the overall dimensions of more than 20 cm and a thickness of more than 5 cm, should undergo piece-by-piece inspection by ultrasonic or other similar method.

At least 50% of inspected forgings should be subjected to flaw detection. The standards and methods of verification should be consistent with the ND.

Nuts and bolts (studs) should be made of steel different brands, and if it is made of steel of the same grade, then with different hardness. In this case, the hardness of the bolt (stud) should be higher than the hardness of the nut. The length of the bolts (studs) must exceed the threaded part above the nut by the length specified in the RD.

The metal of the bolts (studs) must be selected with a coefficient of linear expansion close to the coefficient of linear expansion of the flange metal. The difference in linear expansion coefficients should not be more than 10%. The use of steels with very different linear expansion coefficients (more than 10%) is permitted in cases confirmed by strength calculations.

It is allowed to use nuts made of pearlitic steel on bolts (studs) made from austenitic steel, if provided for by the ND.

If fasteners are produced by cold deformation, they should undergo heat treatment.

Steel castings should be used in heat-treated form. Control mechanical properties castings are carried out after heat treatment.

Non-metallic materials used in the manufacture of air receivers and pressure vessels should be compatible with the substances that will come into contact with the air receiver in terms of corrosion resistance and insolubility (change in properties) when operating temperature. The medium for which the pressure vessel will be used must be specified in the passport for the air receiver or air collector for compressed gas. The use of non-metallic materials is permitted with the approval of the Gosgortekhnadzor of the Russian Federation on the basis of permission from a specialized institute.

For metal-polymer air receivers and pressure vessels, the material of the sealing layer is selected so that when the air receiver is tested with test pressure, plastic deformations do not appear in the material. The methodology for calculating the deformation-stress state of the air receiver and experimentally identifying residual deformations is agreed upon with a specialized institute.

The binder and filler materials used for the production of the air receiver should have guaranteed service life, which should be specified in the certificate for these materials.

Cast iron castings made of high-strength cast iron must be used thermally treated.

The strength of heat-treated threads made by rolling is specified in the ND.

Group 99 Installation of air collectors

Scope of work: Drilling holes for fasteners, installing and sealing fasteners. Installation of air collectors. Connecting air collectors to pipelines using threads or welding.

Meter: 1 air collector

Group 100 Installation of thermal elevator units

Scope of work: Drilling holes for fasteners, installing and sealing fasteners. Installation of an elevator unit. Fitting and welding flanges onto pipe ends. Connection of flanges with bolts and gaskets.

Meter: 1 node