Connectors are designed to accommodate tubing of varying hardness (durometer) — from soft and flexible like PVC and silicone, to semi-rigid types like polypropylene, polyethylene, polyurethane and ethylene vinyl acetate (EVA). To accommodate these varying styles of tubing and their respective application needs, different connector types are used, including barbed connectors, check valves, Luer connectors, quick-acting couplings, threaded luer fittings, and tube-to-tube connectors. Of these, the most commonly used tubing connectors are tube-to-tube connectors, Luer fittings, and quick-acting couplings. These basic connector styles can cover a wide range of liquid and air applications in laboratory and industrial environments.
Tube-to-tube connectors — a popular choice for applications that do not require the disconnection of equipment or parts at any point during production or use. Tubing connectors are available in many different configurations, sizes and material options to adapt different tube sizes or styles, reroute the flow direction without kinking, and act as a manifold.
Luer connectors — delivery systems can employ conical or taper seal connectors, called Luers, to link various system components. The male and female components of Luer connectors join together to create secure, yet detachable, leak-proof connections with no O-ring or gasket required. Luer connectors come in a variety of configurations adapting to tube connections, threaded connections (UNF, NPT and metric) and other Luer or quick coupling terminations. Some of those incorporate a tapered UNF thread, similar to a pipe thread, which can also seal on the thread due to interference on the pitch diameter, facilitating directional alignment with tees and elbows.
Quick-acting couplings — allow flexible tubing and equipment to be quickly and safely connected and disconnected. They may be preferred over general connectors for fluid control because they can incorporate built-in shut-off valves that prevent spillage, allow multiple disconnections and faster servicing.
Many of the latest quick coupling designs focus on the user interface and are equipped with intuitively simplistic thumb latch and side latch mechanisms to make handling easier in laboratory and industrial applications. Quick couplings mitigate the prospect of accidental misconnections and create quicker and safer device connections.