/ http://www.slideshare.net/images/logo.gif / 際際滷Share feed for 際際滷shows by User: AhmedAbseed https://cdn.slidesharecdn.com/profile-photo-AhmedAbseed-48x48.jpg?cb=1551601421 Maintaining pumps, blowers, compressors, conveyors, and crushers. Preparing necessary mechanical spare parts, designs, and modification in order to keep plant at its highest possible production rate. Selecting between various descriptions and costs. collecting data as much as possible so that can choose between alternatives keeping in one hand performance and in the another cost.