Analysis of the absolute and the relative transmissibility on the centrifugal pump

In this paper, we proposed a new technique on the relative transmissibility which are generally only known as the absolute transmissibility or transmissibility. Relative transmissibility is ratio of the relative deflection amplitude of the isolator to the displacement amplitude imposed at the foundation. Absolute transmissibility is ratio of the vibration amplitude of the equipment to the vibration amplitude of the foundation. Centrifugal pump system which is supported by foundation in the form of A36 steel hollow rectangular has one degree of freedom. This method lead to calculate absolute and relative transmissibility ratio both normal pump and damage pump with variation of spring stiffnes and coefficient damping. Relative transmissibility is significant only in an isolator used to reduce vibration transmitted from a vibrating foundation. It is proven theoretically and experimentally that pump with the A36 steel as the foundation has relative transmissibility less than one, which means that system has a good isolation. The minimum value of spring stiffness which is used of isolation system to have a good isolation is 10⁷ N/m. This research opens opportunities for industry in determining type of material used for machine foundation which is related to the value of spring stiffness.