Design and construction of a pneumatic transfer control unit for cyclic neutron activation analysis

Abstract

Pneumatic Transfer System (PTS) is an auxiliary system of Ghana Research Reactor -1 (GHARR-1) to transfer sample capsule in and out of the reactor irradiation sites. The PTS controller unit design and construction was carried out because the transfer system was not designed to operate in cyclic Neutron Activation Analysis (NAA) and as a result could not determine radionuclides whose half-lives are equal or less than 100 seconds. In addition, most of the components used to design the present one-short conventional NAA controller unit are outmoded and out of market, posing threat to future maintenance. To address these situations, a Programmable Logic Controller (PLC) has been used to design and construct a control unit to facilitate a cyclic neutron activation analysis for the PTS. The design has been simulated successfully using a LOGO Soft Comfort software, version 8. Function block diagram programming language was used. The constructed control unit has been tested experimentally using 220 AC volts electric bulbs to represent solenoid valves. The results show that the sample- IN and sample-OUT bulbs come ON and go OFF to represent the solenoid valves’ opening and closing for sample transfer. The results obtained from the study would eliminate the difficulty of getting up-to-date components to replace the outmoded ones in the PTS control. The study has shown that the computer based PLC controller unit for PTS is capable of facilitating both cyclic and conventional NAA application for GHARR-1 and especially, the Miniature Neutron Source Reactors