On-Site Service. Successful inspection of 2 ply testable bellows in the Middle East
In two ply testable bellows each ply is designed for the full operating conditions (pressure, temperature and movements). If a hole or stress crack develops in the inner ply during service, the outer ply takes over without exposing operators to increased risk or creating the need for an unscheduled shutdown.
The objective of this test is to confirm that there are no leaks in the outer ply or in the inner ply and that there is no leaking in the connection welds either. The test is carried out pressurizing the existing space between layers, and observing that there is no decrease in pressure. If the bellows fails to maintain pressure, a soapy bubble check on the exterior surfaces and welding attachments can be performed to determine the location of the leak.
On this occasion, our engineers provided our client with an exhaustive inspection and check of a large number of 2 ply testable bellows installed at his plant in the Middle East.
The life of the expansion joints varies with the design, storage conditions, installation practices, application, and service. Appropriately timed inspections, repairs, and/or replacement of critical joints will ensure the reliable operation of the associated equipment and of the whole plant.