Mechanical Loading Arms
Loading arms are flexible piping systems used to transfer chemicals to railcars, trucks, tankers,
ships, and barges. If the loading arm is going to be used for transportation systems such as trucks or railcars, they will either be top-loading or bottom-loading. For ships and barges, marine loading arms (also known as mechanical loading arms – MLA) are used.
These loading arms have swivels joints, which is what enables the piping system to be flexible. The swivel joints typically have, a split flange design to make it easy to swap product seals without having to disassemble the entire swivel joint. The swivel joints are usually made of stainless steel, while the mechanical seals used are polymeric or elastomeric.
In many designs you will find a nitrogen drying system included. This consists of a cavity located between two the product seals into which nitrogen is injected. The purpose of the nitrogen is to prevent the product from being contaminated by moisture from the atmosphere.
For more information on Cryogenic seals check out the following posts from the Advanced EMC Technologies Blog: