A device to provide a seal between a housing (11) for a moving element (10) such as a drill chain, piston or the like and the moving element. The device comprising a storage well (13) to retain seal material, the block having an outlet connecting with an aperture in a housing enabling seal material to flow into the space between a housing and the moving element (10) and form a seal, the device further including an inlet port (16) enabling seal material precursor to be added into the block, newline pressurising means (14) to pressurise the seal material precursor and force it out of the aperture.

An apparatus (102) for replacing equipment at a wellsite, the wcllsitc having a subsea stripper (104), in use, installed proximate a subsea borehole, which apparatus comprises:

at least one seal assembly portion (130) positionable in the subsea stripper and replaceable therefrom, the at least one seal assembly portion (130) comprising a packer extendable within the subsea stripper (104) to form a seal thereabout;

at least one seal replacement arm (204) for replacing the at least one seal assembly portion (130) through a door of the subsea stripper (104); and

an actuator (208) for remotely actuating the at least one seal replacement arm (204) to engage the at least one seal assembly portion (130) whereby the at least one seal assembly portion is remotely replaceable.

A wiper device is provided comprising a container (1) having a central opening (4) through which the well string may pass. A pair of opposed wiper pads (9) disposed in a horizontal attitude are mounted in spaced vertical relationship within the container (1) for longitudinal movement toward each other, to engage the vertical string. A double-acting pneumatic cylinder (25) actuates each pad. Each cylinder (25) is mounted in the plane of the pad (9), said cylinder being connected at its front end with the rear portion of the wiper pad and being pivotally connected at its rear end with a support member. The front end of the cylinder (25) is thus adapted to rotate in a horizontal plane about its pivot connection, to accommodate transverse movement of the attached wiper pad (9). The container side walls (3) are spaced from the wiper pad edges to permit such transverse movement to take place. Arrays of anti-friction rollers (8) support each of the pads. The spacing of the walls (3), pivoting capability of the cylinder (25) in a horizontal plane, and provision of the anti-friction means (8) combine to permit transverse movement of the wiper pads (9). The head ends of the cylinders (25) are interconnected by a line to enable air, displaced from one cylinder, to move to the other, to permit of longitudinal movement of the pads. The head ends of the cylinders (25) are also connected with a pulsation tank, so that if both cylinders are simultaneously contracted by passage of an enlargement through the pads (9), there is little change in wiping pressure. Thus the pads (9) can free-float with the well string, while maintaining a substantially constant wiping pressure.

The disclosure relates to a sleeve (200) for fitting around a spooling drum : the sleeve comprises at least a groove (202) for receiving a conveying element to be spooled around the drum, is made of flexible material and is configured so as to be able to take a first configuration in which the sleeve forms a flat sheet, the groove extending in a direction, called spooling direction, and a second configuration in which the sleeve forms a cylinder, with the groove is situated on an external face of the cylinder.