Bagpipes are a folk instrument that is typically associated with Celtic culture. They produce a unique sound that is not commonly used in orchestral music. Additionally, bagpipes are quite loud and can be difficult to balance with other instruments in an orchestra.
As a result, bagpipes are not often used in orchestral music. There are a few notable exceptions, such as the works of Scottish composer Sir Alexander Mackenzie, who incorporated bagpipes into some of his orchestral compositions. However, these instances are relatively rare.