Correia, LDC & Jacobs, J 2024, 'Effect of paste pump performance on the transient pressures and forces in an underground distribution system', in AB Fourie & D Reid (eds), Paste 2024: Proceedings of the 26th International Conference on Paste, Thickened and Filtered Tailings, Australian Centre for Geomechanics, Perth, pp. 441-452, https://doi.org/10.36487/ACG_repo/2455_35 (https://papers.acg.uwa.edu.au/p/2455_35_Correia/) Abstract: One of the most important aspects of any paste backfill system is the transport of paste from the paste plant to the underground stopes, referred to as the underground distribution system (UDS). The reliability of the UDS can directly affect both the mining sequencing and the binder consumption; two aspects which heavily influence operating cost. As an integral part of the UDS design, paste pumps are often required either due to the location of the paste plant relative to the orebody, or the geometry of the orebody. Most paste pumps are equipped with a dampening system for suppressing transient pressure surges caused by changes in the flow rate when switching from one piston stroke to the next. The pressure surges can be minimised by limiting the momentum change at the beginning and end of every pump stroke. However, not all dampening systems are created equal, and a poor dampening system design will negatively impact the operation of the UDS. This paper discusses the fundamentals of transient analysis and how the paste pump selection affects both the design and operation of the UDS. The purpose of this paper is to provide the reader with key criteria to be considered before procurement of the paste pump and design of the underground paste pipeline system. Keywords: paste backfill, hydraulic piston pump, piston diaphragm pump, transient analysis, dampening system, underground distribution system, water hammer