Stopcocks & valves

Start with what the stopcock is built into. For glass apparatus such as separating funnels, burettes or vacuum lines, choose a glass stopcock with a ground-glass or PTFE key, for example the two-way stopcock with PTFE key; matching parts are in ground-joint glassware. For tubing and syringe set-ups, a Luer stopcock is more practical, such as the metal three-way stopcock with Luer lock connections. To empty drums, canisters or IBCs, you need a discharge tap that fits the container's thread. Not sure which one you need? Write to sales@luminixhealth.com.

A PTFE plug needs no grease, so it cannot contaminate your sample and is less likely to seize in the barrel. That makes it the usual choice for routine work with solvents, for example the two-way stopcock with PTFE key. A ground-glass plug gives a very tight seal and is common in high-vacuum work, but it needs a thin film of grease to turn smoothly and seal well. One example is the two-way stopcock with glass key. If grease would interfere with your analysis, choose PTFE. More glass components are in ground-joint glassware.

The tap has to match the container's thread exactly. Many standard IBCs use an S60x6 coarse thread, for example the IBC discharge valve with hose screw connection, S60x6 / 1 inch, which lets you attach a hose without an extra clamp. Canisters often have different threads, so check the neck before you order. Another option is a jerrycan supplied with a matching tap, such as the compact jerrycan and tap set, 5 l, electrically conductive, which avoids fit problems when you work with flammable liquids. Send us your container's thread size at sales@luminixhealth.com and we will confirm the right tap.

Take the plug out after use and rinse plug and barrel with a suitable solvent, then let them dry. Do not leave glass plugs sitting in the barrel during washing or storage, because they can stick. Before you put a glass plug back, apply a thin, even film of grease around the plug, away from the bore, for example the silicone stopcock grease, medium viscosity, 35 g. Do not grease PTFE plugs; just clean them and check that the retaining clip or nut holds them firmly. Replace any plug that is scratched or leaks. Spare parts are in ground-joint glassware.

A stopcock opens and closes a line, or directs it between ports. Glass stopcocks have a ground plug that needs grease or a PTFE key. The bore decides the flow. A two-way and a three-way key are different parts.

Tubing is how a liquid or a gas moves between two vessels without being poured. Silicone stays flexible and survives repeated autoclaving. PTFE resists almost every solvent and is stiff. PVC is the ordinary flexible line for water and for mild aqueous work. The fitting, not the tube, is what usually leaks: the barb, the thread and the stopcock have to match the tube bore. Glass and plastic apparatus around these lines is indexed under ISO laboratory ware.

This shelf belongs to Tubing, hoses & fittings, inside Labware. Luminix Health distributes this range for laboratory use.

The neighbouring shelves are Hose connectors, adapters & fittings, PVC, PTFE & other tubing, Silicone tubing and Tubing accessories. The category above this shelf is Tubing, hoses & fittings.

Luminix Health distributes this range from the heart of Europe. We deliver across the EU in two to five days if in stock. Standard delivery is free from €250 excl. VAT. Cold-chain goods and dangerous goods under ADR are never included in that free delivery. The terms are in the Shipping Policy. Send a quote request, contact the team, or read who we are. The full brand index is on shop by brand.

The seven catalogues are Labware, Lab chemicals, Lab instruments, Lab consumables, Chromatography equipment, Lab safety equipment and Life Science & Microbiology. If the article is not on the shelf, request a quote.