These are companies that act as subcontractors to steel fabricators and other construction players. They often receive drawings of the parts to be produced from detailing offices outside the company. They can also act as steel suppliers for their customers. They manufacture parts of all kinds, even if most they are often simple parts that pass through cutting and drilling machines and do not require additional operations. The optimization of steel is crucial for this type of company so they must be rigorous in the management of scraps. In addition, the algorithms for bar and plate nesting are essential and must allow them to mix the different projects on a nesting. The respect of deadlines is also an important aspect, so production must be planned as precisely as possible. The organization of the production is all the more necessary as the customers are numerous and the business represents multiple contracts to manage.