The present invention provides a non-return valve for a resin injection system, especially for use in electrical cable joints, comprising: a valve housing which includes an outlet for a fluid flowing through the valve; and a valve body which is held by the valve housing and is freely movable between a closed position, in which the outlet is substantially sealed or closed to fluid flow by the valve body, and an open position, in which the outlet is substantially open to fluid flow. Thus, with the present invention, the valve body can be loosely held by the valve housing and the valve need not include any spring means to bias the valve body to the closed position. The invention also provides a resin injection system for sealing a localized breach in an object, such as an electrical cable joint.

According to the present invention a sheet handling apparatus is provided which comprises a rotary drum with openings at its peripheral wall. A strip with perforations formed therein spirals circumferentially over an outer surface of the drum in a circumferential spiralling direction, such that a screen is formed over the drum. A suction system controls a flow of air through the perforations thereby to attract sheets towards the drum. The strip is biased by means of a tensioning assembly, which exerts a tensioning force on the strip substantially parallel to the circumferential spiralling direction of the strip.

According to the present invention a sheet handling apparatus is provided which comprises a rotary drum with openings at its peripheral wall. A strip with perforations formed therein spirals circumferentially over an outer surface of the drum in a circumferential spiralling direction, such that a screen is formed over the drum. A suction system controls a flow of air through the perforations thereby to attract sheets towards the drum. The strip is biased by means of a tensioning assembly, which exerts a tensioning force on the strip substantially parallel to the circumferential spiralling direction of the strip.