A static mixer nozzle is a disposable part that sits on a two-component cartridge or dispense valve and blends resin and hardener as the material passes through fixed internal elements. It has no moving parts and no drive. Every version you can order is defined by exactly four things: the interface that attaches it, the element geometry and count inside, the bore and length of the housing, and the ratio family of the cartridge feeding it. This page maps those four dimensions and points to the detail page for each one, so a part number stops being a code and becomes a set of decisions.

The four orderable dimensions

Suppliers describe mixers with long attribute lists, but a buyer only ever commits to four values. Everything else — colour, packaging, whether the housing is natural or opaque — follows from the material choice or from the line’s preferences.

The four dimensions and who constrains each one

Rows are orderable choices, not quality grades. The third column is usually fixed before the mixer is discussed at all.

Read the table top to bottom and note that the constraints narrow as you go down. By the time you reach the ratio family, the decision has usually already been made by whichever cartridge the plant buys. That is why specifying a mixer from the material backwards tends to produce a part that mixes well but does not fit.

Interface: the one dimension you cannot fix later

The interface is a mechanical and sealing decision, not a mixing one. It determines whether the mixer stays on the cartridge under dispense pressure, whether it can be rotated to a comfortable angle, and whether it can be removed without damaging the outlet.

Two families cover most two-component dispensing work. Bayonet-style inlets twist and lock onto a matching cartridge hub and are the common format on 1:1 and 2:1 cartridges in the 200–400 ml range. Luer-style inlets rely on a taper to seal and are common where a specified dispense tip has to be fitted downstream of the mixer. The two are not interchangeable, and neither is improved by adding thread tape, an o-ring, or a clamp.

The interface is also where a mismatch usually shows up first. A mixer that does not seat fully will leak at the joint long before any mixing problem appears, and the leak is often misread as an adhesive or pressure fault. If material is escaping at the cartridge–mixer joint rather than inside the elements, the leaking mixing nozzle troubleshooting guide works through the usual causes in order.

The interface system also has its own naming conventions — A, B, C and F systems, and the MA / MB / MC / MCX families that follow them. Those codes describe which cartridge a mixer will seat on, and they are worth reading properly rather than assuming equivalence from a similar-looking hub. Two mixers that look identical from the outside can differ by a fraction of a millimetre at the locking lugs.

If your question is which system code matches which cartridge, the A, B, C and F interface selection guide walks through the classification, and the MA / MB / MC / MCX interchangeability guide lists which mixer formats seat on which cartridge. Both are more reliable than matching by photograph.

Element geometry: helical or square

Inside the housing, the elements split the stream, rotate it, and recombine it. Two geometries do most of the work in cartridge dispensing. Helical elements form a twisted path that continuously rotates the material around the axis. Square, or quadro, elements use angled plates that repeatedly divide and re-orient the flow through a rectangular cross-section.

The practical difference is not “which mixes better” in the abstract. Helical mixers generally deliver a given mixing quality in a shorter length, which matters when the mixer has to fit inside a nozzle recess or a robot envelope. Square mixers tend to produce a more uniform residence pattern across the cross-section and are often chosen where the bead is wide and the flow is slow. The trade-offs show up as waste volume, pressure loss, and sensitivity to the element-to-housing fit.

If you are choosing between the two for a specific adhesive, the comparison in helical versus quadro static mixers sets them against waste and length rather than against a generic performance claim, and the full selection guide covers how geometry interacts with diameter and cartridge volume.

Element count is a mixing target, not a maximum

Element count is the number buyers ask about first and understand last. More elements mean more splitting and recombining steps, so mixing improves — up to the point where the two streams are already uniform. Past that point the extra elements mostly add pressure drop, dead volume, and purge waste.

Two variables move that point. The first is the ratio: a 1:1 system has two streams of similar volume entering the first element, while a 10:1 system introduces a small B stream into a much larger A stream, and the first few elements have to distribute that small stream before any homogenisation can happen. The second is viscosity difference between the two components. A large mismatch needs more elements than the ratio alone would suggest.

Streaks and uncured patches are not always an element-count problem, though, and adding elements to fix one can make the bead worse. The practical fixes for the defects that actually appear on the bench are collected in tips for effective epoxy mixing with nozzles.

What each additional element buys — and costs

Directions, not values. The actual trade-off depends on bore, formulation and dispense rate, and has to be measured on your own material.

The element count question has its own dedicated treatment: how many static mixer elements you really need works from mix ratio, and element count, mix quality and waste compares the count against what it costs in retained material.

Bore and length are pressure decisions

Bore is the internal diameter of the housing. It sets the flow area, and flow area is what converts your dispense rate into pressure loss. A smaller bore gives finer control and a shorter mixer for the same element count, at the cost of a steeper pressure curve. A larger bore flows more freely but needs more length to reach the same mixing quality.

This is where most “the mixer is too stiff” complaints originate. The mixer is often correct and the combination of bore, element count and dispense rate is wrong for the gun. Manual applicators have a comfortable force range; past it, the operator changes technique, which changes the bead. On a valve, the same mismatch shows up as pressure alarms, inconsistent shot size, or adhesive forced past the cartridge piston.

Treat bore, element count and dispense rate as one triple. Changing any one of them changes the other two in practice. The diameter and length section of the selection guide covers how the triple behaves across cartridge volumes, and static mixer back-pressure explains why excess restriction can produce an off-ratio bead even when the cartridge is fine.

Ratio family changes the inlet, not the mixer

Cartridge ratios — 1:1, 2:1, 4:1, 10:1 — describe the volume relationship between the two barrels. They do not describe the mixer, but they do change what the mixer’s inlet sees. In a 10:1 cartridge the B-side outlet is small, and the mixer inlet has to accept that small stream and fold it into the larger one without letting it run down one wall.

This is why a mixer that performs well on a 1:1 cartridge is not automatically right for a 10:1 cartridge of the same volume, even when the interface is identical. The first two or three elements do the distribution work, and their geometry is what the ratio actually constrains.

Ratio also decides how the material behaves after mixing. A 1:1 system has more B component per unit volume, so the same incomplete mixing produces a different defect than it would in a 10:1 system. The volume-versus-weight guide to mixing ratios covers how the ratio is stated and measured, and mixing nozzles for 200 ml and 400 ml cartridges works through sizing and ratio for the two most common package sizes.

Three pairs that get confused

Most specification errors we see are not arithmetic. They are two different parts being treated as one.

Bayonet versus Luer

Both attach a mixer to a cartridge, and both are described as “connections”. Bayonet is a twist-lock mechanical retention with an integrated seal face. Luer is a taper fit, usually used to hold a tip rather than to hold a mixer under full cartridge pressure. A bayonet mixer on a Luer outlet will not seal, and a Luer mixer on a bayonet hub will not lock.

Static versus dynamic

A static mixer has no moving parts and relies on the flow path. A dynamic mixer has a driven element and can handle short pot life, high filler loading, and formulations that set too fast for a passive path. The 2K dynamic mixing nozzle guide covers where the passive approach stops being viable.

Mixer versus dispensing tip

A mixer blends; a tip shapes the deposit. They sit at the same end of the assembly and are often described in the same sentence, but they solve unrelated problems. The comparison of adhesive dispensing nozzles and mixing nozzles separates the two, and the outlet types overview covers what the mixer’s own discharge end controls.

Turning the map into a sample request

Four dimensions plus the material is enough to request a sample without a drawing exchange. The list below is what a supplier needs in order to send something that can actually be trialled, rather than something that looks similar.

What to send with a sample request

The right-hand column is what the supplier cannot infer — if it is missing, the sample is a guess.

With those eight items, a sample can be specified and shipped against a stated purpose. What still has to happen on your side is the trial: a mixer that arrives without a pass condition cannot be accepted or rejected, only discussed. The epoxy mixing nozzle buying guide covers what belongs on the purchase order, and mixing nozzle qualification sets out a production release test that produces evidence rather than an opinion.

Questions that come up before a first order