Disclosed are chromatography systems employing a releasable coupling (100) for holding a fluid tubing to a spigot, the coupling comprising: a cylindrical inner component (110) for accepting a fluid tubing (30), said inner component including a resiliently deflectable portion (118) arranged to urge an outer surface of the tubing toward a spigot; and a cylindrical collar (130) having and internal through-aperture (132) for slideably accepting the inner component, the aperture and resilient portion having complementary surface formations which in a first position of the collar mounted to the inner component provide for said resilient deflection in use, and which in a second different position do not cause said deflection, the coupling being characterized in that the collar comprises a collar flange (134) extending outwardly away from the aperture of a size allowing manual manipulation of the collar between the first and second positions. Chromatography systems employing said couplings is disclosed also.

A sliding sleeve for axially sliding onto an expanded end of an all-plastic pipe or a plastic composite pipe, into which is slid a support body having circumferential external ribs of an connecting element is made of an elastically-deformable polymeric material. The internal surface of the sliding sleeve has an average roughness value R.sub.a in a range starting from 1 μm to half of the average wall thickness of the sliding sleeve. In another embodiment, the inner surface of the sliding sleeve has a plurality of macroscopic irregularities, the depth of which does not exceed half of the average wall thickness of the sliding sleeve.

Disclosed are chromatography systems employing a releasable coupling 100 for holding a fluid tubing to a spigot, the coupling comprising: a cylindrical inner component 110 for accepting a fluid tubing 30, said inner component including a resiliently deflectable portion 118 arranged to urge an outer surface of the tubing toward a spigot; and a cylindrical collar 130 having and internal through-aperture 132 for slideably accepting the inner component, the aperture and resilient portion having complementary surface formations which in a first position of the collar mounted to the inner component provide for said resilient deflection in use, and which in a second different position do not cause said deflection, the coupling being characterized in that the collar comprises a collar flange 134 extending outwardly away from the aperture of a size allowing manual manipulation of the collar between the first and second positions. Chromatography systems employing said couplings is disclosed also.

A hose adapter may include an outer tube, an inner tube, a hose connector, and a hose. An inner peripheral ring protrudes from the inner periphery of the outer tube while an expanding ring portion protrudes from the outer periphery of an end of the inner tube. The outer periphery of the inner tube further has a first peripheral recess, a second peripheral recess, and a first outer thread, and a first O-ring and a second O-ring are respectively disposed on the first peripheral recess and the second peripheral recess. The inner tube is inserted into the outer tube, and the expanding ring portion is abutted against the inner peripheral ring, and the first O-ring is coupled between the outer tube and the inner tube while the second O-ring and the first outer thread are adapted to pass through and be exposed out of the outer tube.

A leak-proof tube fitting assembly structure includes a liquid tube, a liquid tube fitting, and a nut for locking and connecting the liquid tube and the liquid tube fitting. The liquid tube fitting has a first connecting end, a first threaded connecting portion and a second connecting end that are axially arranged in sequence in a forward direction. The first threaded connecting portion has a first external thread. Thereby, the sealing performance of the connection of the liquid tube and the liquid tube fitting is improved to prevent leakage.

A leak-proof tube fitting assembly structure includes a liquid tube, a liquid tube fitting, and a nut for locking and connecting the liquid tube and the liquid tube fitting. The liquid tube fitting has a first connecting end, a first threaded connecting portion and a second connecting end that are axially arranged in sequence in a forward direction. The first threaded connecting portion has a first external thread. Thereby, the sealing performance of the connection of the liquid tube and the liquid tube fitting is improved to prevent leakage.

A load bearing flexible conduit system for use in a body of water and adapted for deployment from a reel located on a water going vessel into the body of water is disclosed. The system comprises a number of lengths of load bearing flexible conduit, each length of load bearing flexible conduit provided with an inner layer having a throughbore and a load bearing outer layer. A joint for connecting the lengths together has a body having a longitudinal axis and a throughbore and at least one flexible coupling to permit at least one of the ends of the respective first and second lengths of load bearing flexible conduit to move relative to the longitudinal axis of the joint.

A fitting for a pipe has a cylindrical sleeve and a spigot fitted concentrically within the sleeve. The sleeve is slidable along the spigot in a proximal direction. The sleeve has a gripper ring cavity with a conical bearing surface with a diameter that is smaller at the distal end and a larger at the proximal end. One or more gripper rings fit within the cavity and slidingly engage the bearing surface. The spigot has an outer surface sized to fit within a proximal end of the pipe. The inner surface of the gripper rings and the outer surface of the spigot define an annular space with a first radial width sized to accept insertion of the proximal end of the pipe. When the sleeve is moved with respect to the spigot in the proximal direction toward a sealed position, the rings are inwardly compressed by the bearing surface to grip an outer surface of the pipe. The end of the pipe is drawn into a space between the sleeve and the spigot with radial width smaller than the first radial width.

Provided is a hose connector that is protected from inadvertent disconnection, and permits any problem with the hose connection to be readily detected. The hose connector (10) includes a connector main body (12), and a lock member (14) fitted on the connector main body. When the lock member (14) is displaced to a locked position, an annular reduced diameter portion (42) of the lock member (14) approaches an annular enlarged diameter portion (24) of the connector main body (12) so that these two portions clamp the wall of the hose. The lock member (12) is held in the locked position by a second engagement portion (38) formed in the inner circumferential surface of the lock member (12) engaging the connector main body (12). When the lock member (14) placed in the locked position is subjected to a twisting force exceeding a prescribed value, a frangible part (49) provided between the second engagement portion (38) and the annular reduced diameter portion (42) fractures, but the connection of the hose is maintained because the second engagement portion supports the annular reduced diameter portion from the rear via the frangible part (49).

An irrigation pipe coupler can engage an open end of an irrigation pipe with its forward end. The coupler has a nipple and an outer collar. The nipple has an outwardly projecting barb and the collar surrounds the nipple and has an inwardly projecting bulge. The collar is slidably moved along the nipple between forward and rear terminal positions while being kept spaced radially outwardly from the nipple via a peripheral gap that is re-defined for each new position of the collar along the nipple. At each such new position, the gap has a narrow region measured in the radial direction where the collar is closest to the nipple and the narrow region gets smaller at least during at least part of the forward movement of the collar along the nipple. A window formed in the collar allows an operator to see an irrigation hose inserted into the gap.