Manufacturing engineers work in manufacturing plants and factories. They design, implement and maintain production and manufacturing processes. They ensure that plants run efficiently with minimal input from human beings. They are also the guys you call when things go wrong.
A day in the life of a manufacturing engineer involves creating designs for new processes, implementing the designs, and maintaining the existing ones. Manufacturing engineers may also design products and oversee quality control of a production plant. As a manufacturing engineer, it's up to you to ensure a 100% efficiency in the plant with zero waste.
Senior manufacturing engineers may also oversee other workers in the plant, and fulfill administrative duties. To become a senior manufacturing engineer, you must have a bachelor's degree in manufacturing engineering, and possibly a master's degree. Employers also favor professionals with years of working experience when filling this role.