A connecting element for connecting two hollow bodies through which a fluid can flow comprises a first connecting part which can be brought into fluid-tight flow connection with a first hollow body through which a fluid can flow, a sealing element which is arranged at least partially in an inner area of the first connecting part and a locking element which is arranged on an outside of the first connecting part. The locking element can be transferred from an unlocked position into a locked position, wherein the locking element in the locked position acts upon the sealing element in such a way that an inside diameter of the sealing element is smaller than when the locking element is in the unlocked position.

A connecting element for connecting two hollow bodies through which a fluid can flow comprises a first connecting part which can be brought into fluid-tight flow connection with a first hollow body through which a fluid can flow, a sealing element which is arranged at least partially in an inner area of the first connecting part and a locking element which is arranged on an outside of the first connecting part. The locking element can be transferred from an unlocked position into a locked position, wherein the locking element in the locked position acts upon the sealing element in such a way that an inside diameter of the sealing element is smaller than when the locking element is in the unlocked position.

A biocompatible tube and fitting system that can be used in a liquid chromatography system is described. The tube can have a polymer tip and can be used in conjunction with one or more fitting assembly.

A coupling device for coupling to a fluid line includes a coupler body having an end portion with a threaded outer surface and a conical inner surface. A fastener threadedly engages the threaded outer surface of the coupler body. A ferrule includes a rotational driving portion and a clamping portion having a threaded inner surface. When a tube is inserted through the ferrule and the fastener and into the end portion of the coupler body, the fastener threads onto the coupler body and the conical inner surface of the coupler body engages an outer surface of the clamping portion of the ferrule to substantially clamp the clamping portion of the ferrule around the tube. With the fastener tightened, the ferrule is rotatable relative to the fastener and the coupler body and the tube, whereby rotation of the ferrule moves the tube further into the coupler body.

A pipe connecting system for first and second pipe pieces extending along a common longitudinal axis includes a clamp. The pipe pieces each have first end and first clamping surfaces. The clamp has first and second contact surfaces lying against respective clamping surfaces to prevent the clamping surfaces from moving away from one another, while leaving a space between the first and second end surfaces. A retaining ring has a sealing connection attachment to the second pipe piece, and on which a sealing ring is mounted, the sealing ring lying against a circumferential first sealing surface of the first pipe piece. An interior of the first and second pipe pieces between the two pipe pieces is sealed against the surrounding environment by the sealing connection. The two pipe pieces can move towards one another without the first sealing ring moving out of contact with the first sealing surface.

A pipe connecting system for first and second pipe pieces extending along a common longitudinal axis includes a clamp. The pipe pieces each have first end and first clamping surfaces. The clamp has first and second contact surfaces lying against respective clamping surfaces to prevent the clamping surfaces from moving away from one another, while leaving a space between the first and second end surfaces. A retaining ring has a sealing connection attachment to the second pipe piece, and on which a sealing ring is mounted, the sealing ring lying against a circumferential first sealing surface of the first pipe piece. An interior of the first and second pipe pieces between the two pipe pieces is sealed against the surrounding environment by the sealing connection. The two pipe pieces can move towards one another without the first sealing ring moving out of contact with the first sealing surface.

A joint is connected to a tube and includes a joint body, nut, and ring. The joint body has a tube coupling part and a main body thread part. The nut has a nut thread part and a constricted diameter part. The ring is arranged in a space radially inward of the nut thread part. The ring abuts an abutted part of the nut. The ring has a Young's modulus greater than the tube. The ring has a curved surface part at least at a radially inward portion of the ring axially on the joint body side, the curved surface part bulging radially inward of the ring and axially toward the joint body side. A maximum thickness of the ring in a radial direction is defined as 2r, an axial length of the curved surface part of the ring is defined as h, and =h/r being 0.5 to 1.2.

A joint is connected to a tube and includes a joint body, nut, and ring. The joint body has a tube coupling part and a main body thread part. The nut has a nut thread part and a constricted diameter part. The ring is arranged in a space radially inward of the nut thread part. The ring abuts an abutted part of the nut. The ring has a Young's modulus greater than the tube. The ring has a curved surface part at least at a radially inward portion of the ring axially on the joint body side, the curved surface part bulging radially inward of the ring and axially toward the joint body side. A maximum thickness of the ring in a radial direction is defined as 2r, an axial length of the curved surface part of the ring is defined as h, and =h/r being 0.5 to 1.2.

A biocompatible tube and fitting system that can be used in a liquid chromatography system is described. The tube can have a polymer tip and can be used in conjunction with one or more fitting assembly.

An apparatus for coupling together tubular components is described herein. The apparatus includes a coupling assembly with a coupling device having threads and an internal groove. The coupling assembly also includes a retainer clip positionable in the internal groove. The retainer clip is biased to apply a radially outward force against the internal groove when the retainer clip is positioned in the internal groove. The coupling assembly includes a ferrule, coupleable to the coupling device, in contact with the retainer clip when coupled to the coupling device to form an electrically conductive path through the coupling device, the retainer clip, and the ferrule. The retainer clip is configured to prevent movement of the coupling device relative to the ferrule when the retainer clip has an unbiased inner diameter smaller than an outer diameter of the ferrule or the retainer clip is not properly inserted into the internal groove.