About fittings

No matter how expensive or sophisticated an analytical system’s valves, columns, detectors, or integrators might be, if the fittings do not make leak-tight seals, the system will not perform properly. The fittings must also be inert relative to the sample components, provide a flow path which does not induce any turbulence or mixing, and add as little volume as possible to the system.

Fitting designs which best address the aspect of added volume allow the tube ends to butt directly to each other or have bores which match the tubing bore, leaving no dead or unswept volume. Such fittings are called zero dead volume fittings.

Our Valco and Cheminert fitting lines excel in all critical areas of the designing and manufacturing of fittings. Quality considerations, which cannot be ignored if an analytical system is to reach and maintain optimum performance levels, include interchangeability, counterbore tolerances, ID/OD concentricity, mixing potential, cleaning procedures, and the method employed to make up the ferrule on the tube.

Valco fittings

Cheminert fittings

Cheminert fittings are ideally suited for applications requiring an inert, biocompatible, metal-free flowpath. Wetted materials are PFA, FEP, CTFE, or PEEK, and uniform flow passages minimize mixing. All connections have zero dead volume.

High pressure Cheminert fittings
The Cheminert line of high pressure fittings is rated at 5000 psi with fingertight nuts, well beyond the burst strength of most PEEK tubing. Our new Nanovolume™ fittings, with 100 or 150 µm bore, are ideal for high resolution capillary chromatography.

Low pressure Cheminert fittings
Cheminert low pressure fittings are ideally suited for flow injection analysis, low pressure liquid chromatography, and stream sampling devices. They may be safely used at pressures up to 500 psi and temperatures to 50°C.