Pipes are fabricated from:
- stainless steel and titanic alloys with the use of fittings;
- steel, special and copper-nickel alloys with the use of bent runs external diameter of which is 325 mm;
- billets fabricated with rolling method.
This production branch performs:
- pipe cold bending (Rb=1,5 - 3,5);
- fabrication of steeply curved fittings and pipe-bends on the HFC heating plants – NB 50-400 mm and Rb=1,5 from DN made of steel and copper alloy; on the cold bending plants – NB 50-300 mm and Rb=1,5 - 3,5 from DN made of steel and copper alloy, stainless steels and coppernickel alloys;
- assembly of pipes and units on the special mounting stands and piloting plates;
- machining of pipes (about 307 standard types) fabricated from various materials – 6 - 377 mm nominal diameter, 1,5 - 20,0 mm wall thickness;
- chemical cleaning in alkali and acid solutions;
- fabrication of heat insulation which construction depends on pipeline intended use and operating liquid temperature;
- connection ends beveling by pressure method on the turning-bending and boring machines;
- strength tests at 300 kg/cm2 pressure in the enclosure; greater than 300 kg/cm2 – in the reinforced room; Рmax= 800 kg/cm2; room dimensions are 2500x2500x5500 mm;
- tightness tests with threshold sensitivity up to 6,7 х 10 -11 m3 Pa/sec;
- monitoring of hydraulic tests.
Production facilities include argon-arc welding and manual welding stations and sites equipped for general assembly.
Complicated pipe bending has a geometric deviation coefficient not greater than 4% - 6%, wall thinning at the smallest radius of bending within 20% range, internal surface crimping of bending within 3% range. Pipe bends which diameter is greater than 377 mm are fabricated from sectors. Sectorial geometry calculations are computerized.
Pipe fabrication envisages assistance of:
- mechanical production facility to manufacture wayside pipe connections (union connections for pipes not greater than Dn=45 mm, pipe flanges not greater than DN=260 mm) and adapter fittings: connecting adapters, T-joints, cross-joints, bends, L-mounts for pipes not greater than DN=220 mm);
- thermal treatment production for annealing and application of special coatings at low and high temperature ranges (oxidation);
- paint insulation production for application of corrosion resistant coatings;
- electroplating production for application of corrosion resistant and decorating coats;
- specialized production for fabrication of billet pipes from longitudinally welded plate and titanic alloy pipe welding.
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