Flexible metallic strip wound tubes are manufactured from a helically wound pre-formed strip, generally with right-hand lead where the turns, with or without packing, are connected together by single or double overlapping. The flexibility is obtained by sliding adjacent turns on each other.

There are three types of strip wound tubes distinguished by their principle of manufacture and sealing characteristic:

• leak proof tubes: suitable in applications for pressure (pressure tubes),
  

• tubes with limited leak profess: suitable in applications with low pressures and permissible leakage loss of fluid (extraction and exhaust tubes),
  

• non-leak proof tubes: suitable in applications without pressure (protective tubes).
  

MATERIAL
Flexible metallic tubes usually in heavy-duty conditions. In comparison with rigid tubes, they have less thickness of wall and therefore shall have superior anti-corrosive. The ideal materials to be used in the manufacture of flexible metallic tubes must meet the following requirements:

• working ability by plastic deformation,
  

• good strength properties,

• optimum thermal stability,

• anti-corrosive properties,
  

• reliability in operation.
  

In principle, there is no material which will ideally meet all these demands. The materials, used for our range, cover a large variety of needs occurring in practice.

Flexible metallic strip wound tubes are in a standard manner made of the following materials:

• stainless steel AISI 304 to ASTM A 167 (DIN 17440) W.Nr. 1.4301, NF A 35-572 Z6 18.09 to JUS C. 4580),

• carbon steel C. 0148 to JUS C. B4. 016 (DIN 1623 W.Nr.1.0338.6) galvanized in Gal Zn3 to JUS C.T7.111.