Case story



South America


Belman received a request from a producer of ammonium nitrate used for mining explosives in South America for two same-design replacement Gimbal Expansion Joints. Belman designed and produced an updated version of the Expansion Joints to meet the latest design code version.


The client contacted Belman as it had two Expansion Joints with leaking Bellows and was looking to replace them. After many years of reliable operation, the Expansion Joints had reached the end of a long service life. The client was happy with the Expansion Joint solution and wanted to continue using the same design. The client was therefore looking for a manufacturer that was able to update the existing design to meet the prevailing design code version of EJMA and also produce it. Although Belman was not the original manufacturer of this solution, the client turned to us for the new Expansion Joints.


BELMAN SOLUTION – bringing a design up to date with the latest design code version
Belman updated the design of the Gimbal Expansion Joints with double bellows from EJMA 8 to EJMA 10, which resulted in some minor changes, mainly in the supporting parts. The Expansion Joints were still designed for the same amount of movement, the same number of cycles and in the same size and length as well as for the same design temperature and design pressure. The spring rates of the new design were much lower than in the original design. Belman ensured that the updated design was able to absorb the same amount of angular movement as its predecessor. Besides the updated design the client requested the same materials as in the original Expansion Joints.


Materials resistant to the harsh environment and media
As the Expansion Joints work as discharge joints for the acid storage tanks (sulfuric acid), the materials need to be highly resistant to the harsh surroundings and the acid media. The Bellows are therefore made from Incoloy 825, which is a material with a high nickel content for long-lasting resistance to stress corrosion cracking in the harshest of environments. The inner sleeve is made from 1.4307 (AISI 304L) as this is preferred for nitric acid applications as well as other severely corrosive media. The other parts on the Expansion Joints are made from the materials 1.4307 (AISI 304L) and 1.4571 (AISI 316Ti).


Belman – expertise in Expansion Joints for mining
Belman has been supplying mining facilities around the world with Expansion Joints since 1994. Having this vast experience enables us to design and manufacture sound and cost-efficient Expansion Joint solutions for the mining industry, irrespective of client needs or application. This also includes same-design Expansion Joints and/or updating same-design Expansion Joints to the latest standard. Read more on our webpage: Expansion Joints for the mining industry