Stainless steel bellows are utilised where either temperature, pressure or media prevent the use of rubber bellows—produced from thin wall tubes with the number of convolutions determining the available movement.
With a bellows unit, only a few convolutions are safely engineered before the unit becomes unstable under pressure.
Additional bellows could be installed for more significant movement requirements, or an alternative system design must be employed.
As specific design criteria are generally the case with each expansion problem, each bellow is designed and manufactured to customers’ requirements, including length, pressure, end termination and movement requirements.
Axial bellows, designed to absorb thermal expansion in straight pipe runs operating below 10 bar, require installation between two anchor points with sufficient guides along the total pipe length.
Double-tied bellows, are positioned 90 degrees to the main pipe run, absorb thermal expansion in a lateral plane, offering greater movement capabilities in two lateral planes. These units also accommodate some axial movement.
Double-hinged bellows, positioned similarly to double-tied bellows, absorb large movements, allowing lateral movement in only one plane due to the hinge brackets. Double-hinged systems are ideal for high-pressure applications or where forces from thermal expansion on anchor points cannot be contained.
Single-hinged bellows, utilizing a two or three-pin system to accommodate substantial expansion, work similarly to double-hinged bellows and are well-suited for high-pressure applications.
End fittings for each bellow include a range of terminations such as fixed or swivel flanges, stub pipes, BSP male and female threads, and copper stubs.
