Metal hose

General characteristics
Metal hose is a connecting flexible piping elements that are designed to transport liquid or gaseous media under high or low pressure, while ensuring the integrity of the circuit in a wide temperature range,
Design features
The main element for the flexibility of the sleeve, is a corrugated part which is manufactured from corrosion-resistant high-alloy steel. Strengthens the structure of metal braid, which allows to operate the arm with the highest pressure. Corrugated sheath is made by winding over the tops of the corrugations of the profiled ribbon. The corrugations can be helical or annular. Sleeve with a spiral (helical) arrangement of the corrugations are reinforced by the diameter of the wire spiral. The ring bumps — more widespread, because in conditions of high pressure under longitudinal tension they are not subjected to twisting. The main power element of the metal sleeve is a braid, which serves to protect the sleeve from unexpected damages. Braid under the influence of radial and axial loads, including surge pressures during transport of liquids or gases through the system must ensure the performance of the sleeve.
Production
Metal hoses are manufactured in single and multiple braids, the number of which depends on the values of working pressure. The braid provides performance when exposed to radial and axial loads and pressure surges, which are unavoidable when moving liquid or gaseous media through the pipeline. This braid is usually a mesh type of stainless steel 12X18H9T section 0,3; 0,4; 0,5; 0,6 mm. For coupling with the main circuit serves as a reinforcement for the end of the sleeves. To the flexible sleeve and fittings attached to solder acid solder or welding (GTAW or pin-roller). The braid extreme corrugations in the place of embedment of the reinforcement is put on the glass that protects a portion of the corrugations from the thermal effects of welding and brazing. If necessary, allowed by agreement with the customer welding connection special fittings, which is developed according to his plans. The inner and outer surface of the metal conduit must be without gross mechanical damage, visible impurities and other defects which are not provided specifications for the materials. Braided sleeves should fit the sleeve tightly and not have projecting broken strands and wires.
Dimensions
Metal hose are with different internal passage diameters of the corrugated containment up to DN 300 mm. the size of the connecting fittings butt weld in the form of rings mounted on the basis of requirements regarding operating pressure for hoses. To meet the requirements of TU — free bending length of the hose should be at least 250 mm. In coordination with the customer is possible to produce the sleeve Assembly method for joining several hoses. This joining is performed by welding the weld rings.
Use
Metal hose is designed to transport production environments at t° to 400 °C. When ordering sleeveless, you must specify the transported medium, operating temperature range etc. parameters. Working pressure (P slave.) — the pressure of the transported medium, in daily use. Nominal pressure (PN) — working with the greatest pressure at which it is allowed to work the sleeves in normal operating conditions. Due to the reliability and long service life flexible metal hose is widely used in vehicles, aircraft, shipbuilding, industrial chemistry, metallurgy, thermal power, to create cryogenic equipment.
Dignity
The absorption of vibration; transportation of liquids or gases under conditions of temperature drop and pressure; protection from accidental injury; ensuring reliable connections with movable equipment; the elimination of inaccuracies in the mounting of the contour. The strength of the spiral wrap are determined by the number of braids, which play the role of reinforcement; corrugated profile parts: parameters of corrugations number of corrugations per unit length; wall thickness and material, which affects the resistance to the environments and conditions mechanical, chemical and thermal effects. Corrosion resistance depends on the resistance of stainless steel 12KH18N10T in the braid and the flexible durability of the item. Particularly harmful pitting corrosion, which cause a chlorine-containing environment and contact with sea water.
Operation
The durability of metal hoses depends on the number of load cycles — one cycle load — displacement of the sleeve and return to its original position. Other factors are: pressure and temperature, the amplitude of their oscillations, the frequency of movement of the sleeve, the minimum bending radius, the impact of aggressive working environment, vibration. The fuel and hydraulic systems, flexible hose under pressure of fluid pulsating nature that can cause destruction of flexible pipelines at pressures on the order of less than static loads. The source pulsations are piston and gear pumps. With a sharp sudden closure of the valve occurs hydrodynamic shock, which also leads to the destruction of the shell. To increase reliability it is necessary to introduce damping devices in the system. During pumping of the working medium through the sleeve may be ceased with the inner surface of the corrugation. In this regard, do not use the hose at speeds of movement of the work products of more than 8 m/s for liquids or more than 50 m/s for gases. When operating with a high level of vibration, you should prevent the occurrence of resonance oscillations.
Performance
Working pressure (corresponding to t° 20°C) is defined as the quotient of the working pressure at the working environment temperature by a factor k, whose values are given in the table:
Temperature, ° C | The coefficient, k |
---|---|
<40 | Of 1.00 |
40 | 0,98 |
70 | 0,95 |
80 | 0,94 |
90 | 0,98 |
100 | 0,91 |
110 | 0,91 |
125 | 0,89 |
140 | 0,88 |
155 | 0,87 |
185 | 0,84 |
200 | 0,82 |
250 | 0,77 |
315 | 0,71 |
400 | 0,69 |
The minimum length of hose
The diameter Dy, mm | The minimum length of hose, mm |
---|---|
6−16 | 250 |
20−50 | 300 |
70−100 | 500 |
125−150 | 800 |
200−250 | 1000 |
Limit deviations of the length of the spiral wrap
The length of the hose, mm | Limit deviations | Diameter more than 50 mm |
---|---|---|
250−300 | ±3 | ±5 |
300−1000 | ±10 | ±15 |
1000−1500 | ±30 | ±30 |
1500−3000 | ±40 | ±60 |
3000−6000 | ±100 | ±200 |
Features of installation
When choosing the length of hose need to have a neutral land around the rebar, not exposed to bending during operation. Sleeve, not having neutral sites may be established only in a straight line or at an offset no more than 20−30 mm for each meter of length. Stretching, twisting and compression sleeves are not acceptable. Limit deviation of the length of the sleeve from the nominal value is 3%. Also will not allow a bend radius of less: 10Dу — for sleeves for critical applications; 5Dy — sleeveless pressure to 100 atmospheres (10 MPa); 12Dy — sleeveless pressure of over 100 atmospheres (10 MPa). Installation to be performed to avoid large loose sections. To prevent sagging you need to apply the clamps, stands, trays, etc. are Not allowed when installing clamps, the deformation of the flexible portion of the sleeve. To do this, use strips of leather, rubber, PTFE and other flexible materials. The docking sleeve with a threaded tip necessary to produce a way to avoid cranking. When docking sleeve with flange tip and PTFE gaskets should be tightened crosswise in pairs.
Corrugated metal hose
Represent a flexible tube made of stainless steel. Depending on the purpose of the use they made of different diameters and designed for different working pressure, Used in industry and construction. In industrial technique, they play the role of reinforcement, are widely used in ventilation systems as a vent. In addition, these sleeves are applied when using flexible hoses for external protection. Sealed ruffled sleeves are used for pumping water and other liquids.
Buy at best price
The range of metal hoses. implemented by the company «Electrocentury-steel» complies with GOST and international quality standards. We offer the most favorable conditions for wholesale and retail buyers. Deliveries are made from warehouses located on the territory of Russia and Ukraine. High quality, affordable prices and a wide range of products define the face of our company. Becoming our regular customer, You will be able to rely on the system of discount discount. Cooperation with us will help You to implement any engineering plans. Waiting for Your orders on the website evek.org.