Metallic multi-layer bellows are intended for operation as sensing elements, phase separators, sealing devices as well as power unit components in atmospheres causing no material corrosion, at a temperature of minus 260°С to plus 550°С.
They are used in glandless valves, dynamic seals, vibration-absorbing intermediate elements, heating systems, pipelines, etc.
Multi-layer bellows are manufactured of corrosion-resistant and fire-resistant steel grades 08Х18Н10Т or 12Х18Н10Т. They provide complete leak-tightness at high pressures and temperatures in combination with excellent flexibility, which is particularly important for hazardous industries.
Bellows operating medium:
-
Gaseous aggressive atmosphere (low aggressive);
- Liquid aggressive atmosphere (low aggressive);
- Steam-gas mixture;
- Water, air, nitrogen;
- Deactivation and washing solutions;
- Inert gaseous medium and liquid non-aggressive media;
- Media to which the bellows material is resistant to.
Metallic multi-layer bellows and their general characteristics
Bellows is a multi-layer tube made of metal with undulated or corrugated surface. Products of this type are able to compress, curve, elongate or displace under the action of temperature, pressure values, etc. This property of bellows is responsible for preservation of the pipeline integrity in case of their use in hydraulic and pneumatic systems as specially sensible elements, which are like a spring: compress or extend depending on pressure, affecting the device itself.
Nowadays, multi-layer bellows made of stainless steel are more often used in modern gas, oil, petrochemical, and oil refining industries. Also such parts can be used for arrangement of a power complex, in automobile industry, shipbuilding and motor-building. They are needed for aerospace industry, military-industrial complex and nuclear industry. Our plant successfully cooperates with organizations and supplies multi-layer bellows for Moscow and Moscow region.
Depending on the grades, bellows made of stainless steel can be operated in various atmospheres: in drinking and hot water, steam-gas mixes, oils, liquid and vapor aggressive media, etc.
For example, thanks to production of multi-layer bellows, based on a number of metal layers, all problems associated to bellows flexibility and material thickness are solved. Herewith, operational life of metallic expansion joints completely depends on the thickness of materials used: the higher is their thickness, the less is their operational life. In case of availability of materials with necessary thickness, multi-layer bellows are able to preserve the required flexibility for a long time.
At present, we are actively developing new, more improved types of expansion joints and bellows, which are at least equal to other worldwide equivalents by their reliability, safety and service life. A high-technology custom-made modern equipment is used for their manufacture. Development and manufacture of these products are conducted in compliance with all requirements of applicable regulatory acts, requirements and standards. Quality of manufactured products is analyzed at all production stages, that’s why multi-layer bellows are issued having only the highest level.
General specifications
Designations of bellows in compliance with GOST 21744-83: dimensions (inside and outside diameter, total length and bellows end), effective area, maximum working stroke and operating pressure
Bellows designation D – n – S x z
|
di, mm
|
do, mm
|
Lo, mm
|
l, mm
|
Fef, cm²
|
λ, mm
|
Р, MPa
|
22 - 6 (8, 10, 12, 16, 20) - 0,16 х 2 (3, 4, 5)
|
14.5
|
16
|
33–91
|
6.9–7.2
|
2.61
|
2.5–7.5
|
4–16
|
28 - 4 (8, 10, 12, 16, 20, 25) - 0,17 х 2 (3, 4, 5, 6, 7)
|
18.5
|
20
|
28–121
|
6.8–7.0
|
4.24
|
1.5–15
|
2.5–20
|
38 - 8 (10, 12, 6, 20) - 0,21 х 2 (3, 4, 5, 6, 8)
|
26
|
28
|
57–136
|
7.0–7.2
|
8.04
|
4.8–12
|
2.5–20
|
48 - 8 (10, 12, 16, 20) - 0,16 х 2 (3, 4, 5, 6, 8, 10)
|
36
|
38
|
54–176
|
7.6–11
|
13.85
|
5.0–17
|
2.5–20
|
65 - 4 (6, 8, 10, 12, 16, 20) - 0,2 х 2(4, 6, 8, 10)
|
46
|
48
|
45–198
|
7.9–8.4
|
24.18
|
3.4–17
|
1.6–12.5
|
95 - 4 (6, 8, 10, 12, 16, 20) — 0,25 х 2(3, 4, 6)
|
73
|
76
|
46–178
|
10.1
|
55.39
|
5.4–32.5
|
1.0–4.0
|
125 - 4 (6, 8, 10, 12) - 0,3 х 2(3, 4, 6, 8)
|
92
|
96
|
75–175
|
14.0–15.1
|
92.41
|
20–40
|
0.8–4.0
|
In 2014, manufacture of multi-layer metallic bellows was successfully developed and launched into production as per GOST R 55019-2012.
Based on the issued products, we have an opportunity to develop and manufacture MULTI-LAYER BELLOWS, EXPANSION JOINTS AND BELLOWS UNITS as per customer’s requirements and drawings.
Ordering
When ordering, it is required to specify the following:
- Description
- Structural design
- Steel grade
- GOST
Example of an order
Multi-layer bellows with outside diameter of 28 mm, number of corrugations 10, wall thickness of 0.17 mm, 3-layered, made of material 08Х18Н10Т as per GOST 21744-83:
“Bellows 28-10-0,17х3 08Х18Н10Т GOST 21744-83”.