Case story


 Fertilizer manufacturing plant


EJMA + EN 14917

Belman has designed and manufactured 7 pcs. two-ply bellows Expansion Joints that meet the special material requirements for installation in a European fertilizer manufacturing plant. Belman has once again demonstrated its expertise in custom design, materials, welding procedures and innovative testing.


Client challenge – complex media composition
The fertilizer manufacturing plant needed an Expansion Joint solution that was corrosion-resistant to handle the aggressive media and would also ensure a long service life. in addition, the client required a solution that could continue to offer trouble-free operation in the event that one ply in the multiple bellows failed. The Expansion Joints were a repurchase as a planned replacement of some old Belman Expansion Joints that has ended their service life.



Two-ply bellows Expansion Joints made from special materials

The two-ply bellows Expansion Joints were a mix of tied Expansion Joint, hinged Expansion Joint and corner relief Expansion Joint solutions designed for the specific locations in the pipeline and its operating data. Due to the critical medium complexity, the Expansion Joints were designed with two-ply testable bellows as per the client’s request for 100% redundancy. The bellows were made from 1.4539 (AISI 904L) with pipe end, flanges and the middle pipe made from 1.4307 (AISI 304L). All these materials were selected to meet the client request of low molybdenum content in the used materials to avoid corrosion.


Two-ply testable bellows

Due to the critical medium, two-ply testable bellows were selected for the design, as they can provide an early warning if a bellow ply fails. Two-ply testable bellows consist of two plies of material with the same thickness. The plies can be made either from the same or different materials. A small space exists between the plies. The bellow is designed in such a way that each ply is able to take up the full load independently. So, if one ply fails/is leaking the other ply will take up the load, operate and ensure pressure integrity alone until the next scheduled shutdown.


Special Welding Procedures (WPS) made due to special material requirements

As the medium in the pipelines where the Expansion Joints are to be installed is a complex chemical composition, special materials were required. The Expansion Joints are made from AISI 904L – and the requirement for them was that they contained a low content of molybdenum, as the combination of the media and molybdenum would corrode the Expansion Joints. This could be avoided by selecting the correct materials and was therefore selected as the solution. Belman is highly experienced in sourcing and working with very special materials, making it the go-to company for many clients who have special requests. Due to the client’s requests for low molybdenum content, special filling material was required as well as special welding procedures. Belman did not have these welding procedures already in place, but as Belman is known for being flexible to meet client needs, we quickly obtained the necessary welding procedures (WPS).


Experienced in the design and manufacture of Expansion Joints made from special materials

Belman is the go-to company for Expansion Joints in special materials. Since 1994, Belman has customised and engineered Expansion Joint solutions for clients in many different industries worldwide. Many of these Expansion Joints are designed and manufactured in special materials. Belman excels in providing Expansion Joint s made from materials such as: Alloy 59, Alloy 188, Titanium (several different grades), Nickel, 254 SMO, Duplex, Superduplex etc.