Abstract: A downhole valve, such as a safety valve or sub-sea safety valve (SSSV). The downhole valve comprising: a housing; a flow path between a valve inlet and a valve outlet; a valve mechanism; and a piston member; wherein the valve mechanism is operable by actuation of the piston member to selectively open and close the flow path between the valve inlet and valve outlet; and the piston member is actuatable by a pressure differential between an annulus pressure at the valve and a pressure at the valve outlet and/or in a portion of the flow path closest to the valve outlet. The valve can comprise an opening for receiving the annular pressure that is isolated from the valve inlet and valve outlet. The downhole valve can be configured such that it prevents operation of the valve mechanism to open and/or close the flow path by a pressure differential between the valve inlet and valve outlet.

Abstract: An expansion apparatus and a method of manufacturing an expansion apparatus are provided. The expansion apparatus comprises an expandable element having a monolithic wall structure circumscribing a longitudinal axis and enclosing a space for receiving a pressurised fluid for use in inflating the expandable element between a non-expanded configuration and an expanded configuration. The wall structure is formed by additive manufacturing to have an initial non-expanded profile in which a perimeter length of the wall structure is greater than an outer gauge perimeter of the wall structure. Expansion during inflation is achieved by reforming the initial non-expanded profile of the wall structure to increase the outer gauge perimeter.