Steel compensators are composed of one or several multilayer, corrugated steel bellows and appropriate connections such as flanged, weld-in or other connections. To form the bellow, a couple of adjacent sheet metal layers is shaped into corrugations. A single stainless steel sheet metal piece is e.g. from 0,2 to 0,5 mm thick. This multilayer design of the bellow ensures much higher flexibility than the single layer design with the same overall thickness and height of corrugations – as, for instance, in the case of corrugated steel hoses. Therefore, the corrugated steel hose cannot substitute the compensator – it cannot accommodate comparable deformation with the same flexibility.

The steel compensators are divided according to the type of pipeline displacement into the following types:

• axial compensators, intended to absorb longitudinal displacement, parallel to the axis of the pipeline and minor lateral displacement. The permissible axial movement is directly related to the number of corrugations. The compensators are simple and compact with one corrugated bellow. Small installation length and easy assembly are the advantages that make these compensators very popular and inexpensive solution used to compensate for displacement of the pipeline, especially due to temperature changes. The pipeline, though, must be secured with supports and pipe guides to carry the stress that occurs in the compensator.
• general purpose compensators, designed to compensate for axial and lateral displacement of the pipeline; two corrugated bellows are separated with a straight section. They do not have any tie rods or hinges.
• lateral compensators, single or double bellow, intended to absorb movements perpendicular to the pipeline axis in all directions. Equipped with expansion limiters – tie rods fitted to the connecting parts or hinge tie rods.
• angular compensators, intended to compensate for angular deflections, equipped with straight hinges (enable angular rotation in one plane – hinged angular compensators) or equipped with Cardan support – gimbal compensators (enable angular rotation in any plane).

The steel compensators are available with an internal steel sleeve to guide the fluid flow. The bellows and internal sleeves are made of the following types of steel: 1.4541 (AISI 321), 1.4571 (AISI316Ti) and other. Flanges and connecting parts are made of carbon steel, stainless steel, acid-resistant steel and other materials. Working temperature range: from -270°C to 600°C. Working pressure: from full vacuum up to several tens of bar. Nominal diameter range: from DN40 to DN6000.

SaniComp compensators are far more effective in absorbing displacement than U-shaped pipelines used in some cases. They are essentially designed for sanitary installations, where hygiene plays an important role. SaniComp compensators are certified by EHEDG – European Hygienic Engineering Group (SaniComp compensators can be applied in utility installations all across Europe). Working temperature up to 200°C (80°C as standard).