Creation of system of heating begins with the project. For creation of reliable system of heating the conciliatory proposal meeting requirements of heating engineers, architects, designers and assemblers is required.
The system of water heating consists of a copper (heat generator), pipelines, the heating devices, control and regulatory and valves. A kind of strapping of the device, i.e. connection schemes to it of bringing and taking away pipes, choose, proceeding from conditions of reduction of volume of installation works, reception more heat of the device or under interior requirements, but taking into account a device design.
Building norms and rules 2.04.05-91* “Heating, ventilation and air-conditioning” resolves “pipelines of systems of heating... To mount from steel, copper, brass pipes, heat-resistant pipes from polymeric materials (including metal polymer, resolved to application in building. Complete with pipes it is necessary to apply connecting details and the products corresponding to applied type of pipes”.
Concerning plastic pipes, except instructions that “the carving on connecting details should be a full profile without broken and threads and to provide shift not less than on one-two threads manually” other recommendations are not present. Concerning copper and brass pipes of any data it is not informed.
For steel pipes in building norms and rules it is underlined that “the thickness of a wall of a pipe should be accepted minimum in accordance with GOST for settlement diameter of a pipe taking into account connection on a carving or welding” and “steel electrowelded pipes should be connected welding” (notes to the appendix 13).
The analysis of separate specifications shows that pipes even from identical materials under the name have, for example, geometrical characteristics, not to mention the physicomechanical short-term and long-term indicators, essentially different from each other.
To same it is necessary to add that now in Russia installation of systems of water heating is made by thousand the organisations numbering from several persons to hundred and more working. Happens so that in their environment, at times, completely there are no professionals. To receive the satisfactory answer to a question as it is qualitative and productive to carry out installation of pipelines of systems of water heating from concrete pipes, practically there is no place.
For today there are, perhaps, two specifications in which data on this question are resulted. These are the arches of rules on designing and installation of systems of heating from metal polymer [the joint venture-41-98 Designing and installation of pipelines of systems of heating with use metal polymer pipes] and copper pipes [Designing and installation of pipelines of internal systems of water supply and heating of buildings from copper pipes].
Let's consider some features of installation of systems of water heating with use of pipes from various materials.
Let's notice that structures of the integrated typical technological processes, sufficient for qualitative and productive installation of systems of water heating, will depend a little on a material of pipes and their diameters.
This statement becomes taking into account following restrictions:
- extends only on systems with traditional trace of pipelines (surround heat-carrier distribution to heating devices);
- basement highways will be mounted while only from metal pipes.
And the maintenance of individual technological processes of installation of pipelines of water heating will depend in many respects from chosen diameters and a material kind.
By the chosen materials of pipes will be defined:
- necessary quantity of fastenings;
- a fixture kind;
- ways of connection of pipes among themselves and with connecting parts.
Copper pipes also have the specificity of connection among themselves and with connecting parts.
Assemblage of steel pipelines carry out on one-piece (welding and the soldering) and demountable (a carving, flanges) connections.
The large building organisations mount steel pipelines, using, basically, gas electric welding.
This way of connection of steel pipes demand high qualification of the technicians who are carrying out installation works, and the special welding equipment that in modern conditions of conducting sanitary-engineering works well only to the large specialised organisations.
It is possible productive and reliably to connect steel pipes the soldering both usual, and magnetic. At connection of pipelines bell and spigot the magnetic soldering on connected elements of the pipeline establishes a magnet which creates a magnetic field between a bell and the pipe inserted into it.
Thus magnetic power lines of a magnetic field are directed across a joint. It allows to fill a backlash between pipes an iron powder. Magnetic, keeps filler in a backlash so that the porous ring is formed. By drawing from above a joint (at a vertical arrangement of pipelines) or near to it (at a horizontal arrangement of pipelines) and heatings to fusion of pastelike solder it is possible to impregnate a porous ring. It provides occurrence at the moment of soldering of capillary forces. They also keep the fused solder between parts of an iron powder. After short cooling it is formed strong connection of steel pipes. For maintenance of necessary heating the multiardent ring torch is used. It should move all time along an axis of joined pipes. After the beginning shrinkage solder the torch acts in film. Durability of the soldering as show the experimental researches, depends on backlash size between accustomed to drinking pipes and length solder connections. The magnetic soldering allows to use steel thin-walled pipes and, thereby, to provide possibility for some reduction of weight of the pipeline of system of water heating.
Small enterprises mount steel pipelines of heating basically on demountable connections on short and long carvings.
At assemblage of pipes on a carving it is necessary to provide them alignment, and also durability and density of connections. Tightness of carving connections of steel pipes is reached by filling with a sealing material of a backlash between internal and external carvings on all their length. Connecting parts (armature) should welling on a pipe with small effort. Otherwise it is necessary to select other connecting parts. If it is not possible to pick up connecting parts satisfying to these requirement it is necessary to use other steel pipe or to cut on an old pipe other better carving. Connecting parts (armature) it is necessary welling on a pipe to the full, i.e. Before jamming on flee. Upon termination of curling the carving should be cleared, and from a surface of a pipe and from connecting parts to remove the rests of a condensing lock. Condensing carvings materials should not collapse at welling connecting parts (armature) on pipes, should harden in a backlash between carvings without air access while in service and should be plastic during all service life of system of water heating. At use of connections of type “a cone in a cone” a carving before connection grease with mineral oil or drying oil, application of an additional sealant is not required. As a sealing material for carving connections of pipelines of systems of heating at temperature of the heat-carrier to 100°C it is possible to apply the linen lock impregnated with minium or whitewash, got mixed up on natural drying oil. It is impossible to apply hemp and substitutes of natural drying oil.
At use of welding of a branching of pipelines are made also by welding. At assemblage of the branched out pipeline in the complete set with steel pipes connecting parts from malleable cast iron (less often steel) with a carving should be used. Them some tens names are.
Carving connections on copper pipes are not applied because of their very thin walls. The main way of connection of copper pipes as among themselves, and with connecting parts is the soldering, however not magnetic, but capillary that is normalised in the corresponding Arch of Rules. Copper pipelines can include connecting parts from same, as well as at pipes, copper, and also from corresponding marks of bronze and a brass, especially for connection of armature and heaters as they include a trumpet carving. Manufacturers provide full compatibility of pipes and connecting parts agree corresponding European norms EN 1057 (round seamless pipes from copper for water-gas pipelines in the sanitary technician and heating installations) EN 1254 (copper and copper alloys, fitting).
Pipes from PP incorporate welding bell and spigot. It is made at interface of the melted off surfaces of details. Melting thin layers on surfaces of the specified details it is made by the heating tool simultaneously. Then the smooth end of one pipe is quickly moved into a bell of other pipe.
Necessary pressure upon interfaced surfaces of pipes is provided with the corresponding sizes of heating tools: internal diameter of a sleeve is accepted on 0.2-0.7 mm more than external diameter of mandrel. The Same parity is recommended for external diameter of a pipe and internal diameter of a bell (in a cold condition the pipe end cannot be moved into a bell of a connecting detail). Welding should be made at temperature on heating surfaces approximately nearby 270° By S.Pri it key parametres of welding resulted, for example, in 40-102-2000 should be maintained strictly. High quality of bell-shaped welding can be provided only at indispensable use complete with polypropylene pipes of connecting parts from the same marks of polypropylene.
For connection of pipes from metal polymer and from the sewed polyethylene among themselves, with armature, devices and pipes from other materials various domestic and foreign firms offer mechanical connections of the diversified design.
The general element of the majority of mechanical connections of the specified pipes is the union.
At assemblage of connections the pipe is put on the union, and other end of the union is carried out with a carving for joining to armature, a collector or the device. The external surface of the union has ring ledges for connection of pipes from the sewed polyethylene, and for connection metal polymer pipes are provided also ring groove for packing in them of sealing rings of round cross-section section. For installation of connections of this kind are used a cutting torch (scissors) for pincers for expansion of a blooming collar and wrenches for screwing of nuts on a bolt on purpose swage the pipe end on the union are sharp pipes, the tool for removal of an internal facet and agnails.
From the sewed polyethylene REH ow compression of the end of a pipe on the union is made for reception of one-piece connection of pipes tension brass clutch.
It is reached as follows. Preliminary expanded pipe then by means of the special device clutch approaches against the stop in an union side is put on the union with ring ledges.
Connections with slip-clutch can be used for pipes both from the sewed polyethylene, and from metal polymer.
For connection of pipes from the sewed polyethylene instead of brass blooming clutch it can be used thermotaking seat clutch from polyethylene.
Elements of connections are made and delivered on the Russian market by numerous manufacturers. Practically each of them has own technology. Therefore all of them can differ from each other on the design and the main thing of accuracy of the sizes.
This circumstance imposes on assemblers special responsibility on assemblage of connections. After all each design is developed for pipes of concrete manufacturers At their use for assemblage of other pipes can contact pressure between corresponding elements are not created demanded for maintenance of tightness of connection.
Complete with pipes from the sewed polyethylene and metal polymer brass and bronze connecting parts, and also from heat-resistant polymers can be used. They on strength indicators should meet the requirements for systems of water heating (it agree building norms and rules heat-carrier temperature – 95°C, internal working pressure in system – 1 MPa and service life not less than 25 years). For example, connecting parts from PPSU correspond to such requirements. Unfortunately, their lack is that they cannot be used again as it is supposed for metal connecting parts.
The best way of connection of H-pvc of pipes is their pasting. Use of connecting parts only from the same material of which pipes are made is thus supposed. Pasting make in the following technological sequence:
- cut, at necessity, a pipe on demanded pieces perpendicularly to its axis, using for this purpose special scissors or hacksaw on metal;
- process the ends of pipes: agnails by means of the special adaptation, scraper or a joiner's knife chamfer and delete;
- select connected details to check up, whether stuck together elements without excessive backlashes each other approach, for this purpose it is necessary to use the measuring tool;
- make preparation of a surface for pasting: special solvent clear connected surfaces, using thus pure rags;
- put an equal layer glue on an external surface of the end of one pipe, using thus a special tampon. Other quantity of glue which remained on a tampon, it is necessary in regular intervals fluff inside a bell surface on other pipe;
- interface surfaces of details to the put glue fast introduction (with simultaneous turn approximately on 1/4 turns) the smooth end of one pipe in a bell (clutch) other pipe against the stop.
Nabiranie glutinous connection of durability, sufficient for carrying out of hydraulic tests of system of heating is necessary to keep the connected details in such position without the appendix of assembly loadings within not less than 1 minute, it is required depending on the surrounding temperature from one about three days.
In summary it is necessary to notice that stated in article, in the majority, has information character. However, in some measure, can be used for improvement of quality and productivity of installation of systems of water heating, both from metal, and from polymeric pipes.
It is quite natural to assume that more effect could be expected in the event that separate positions of article would find the reflexion in the corresponding arches of rules. Authors, apparently from the literature list, have an experience in working out of such documents.
1. Otstavnov А.А., Ionov V.S. Features of installation of pipelines of systems of water heating from metal and polymeric pipes//Arctic building norms and rules. – #17, 2004 [http://www.arktika.ru/rule.phtml? menu=snip& pub=13& page=rule13_7.htm]
2. Polukhin V. Problems of water heating//Ideas of your house. – #1 (14), 1999 [http://www.ivd.ru/document.xgi? id=4098& gid=462& oid=417]
The author: Челябэнергопроект
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