Abstract: A suction diffuser comprising a housing 12 and a strainer element 11. The element 11 is arranged within the housing 12 with its axis in line with the direction of inlet flow into the strainer so that, in operation, incoming contaminated liquid flows first into the interior of the element 11 and then out through the element to the exterior thereof. Particles suspended in the liquid are retained within the element, where there is more space, and sink to the base of the element where they may be removed via a drain plug 15 in the housing 12. In this way the restricted space between the element and surrounding body of the strainer is kept free of material thus avoiding any resultant restriction of the flow.

Abstract: An array processor consisting of a plurality of sections (S1, S2-S9), with switching means (24,26,30,32) selectively operable to by-pass any one of the sections so as to effectively remove it from the system. One of the sections normally acts as a stand-by, and is by-passed. However, if one of the other sections fails, that section is by-passed and the stand-by is returned to service. The currently active sections are allocated sequential addresses.