Hollow cone vs full cone nozzle selection depends on the droplet size your process needs, whether the target’s center requires coverage, and how clean your liquid is.
Both nozzles produce a cone-shaped spray, and a spec sheet comparison alone might suggest they are interchangeable. In practice, the difference in where the liquid concentrates inside that cone, an outer ring versus a fully filled cross-section, drives very different outcomes once you look at droplet size, coverage, and gas-liquid contact. This comparison walks through when each design is the better starting point, using the same kind of side-by-side reasoning as our Spiral Nozzle vs Full Cone comparison.
Quick answer: Choose a hollow cone nozzle when your process needs a fine droplet spectrum and strong gas-liquid contact around the outer edge of the spray, such as gas scrubbing, evaporative cooling, or fine misting, since the ring-shaped pattern concentrates energy into smaller droplets. Choose a full cone nozzle when you need uniform, gap-free coverage across the entire target area, such as washing, coating, or cooling a solid surface, since the filled cross-section leaves no untreated gap in the center. This hollow cone vs full cone nozzle decision ultimately comes down to whether your process values droplet fineness or coverage uniformity more.
The Core Difference: Ring Pattern vs. Filled Pattern
A hollow cone nozzle imparts a strong swirling motion to the liquid inside a whirl chamber before it exits the orifice. Centrifugal force throws the spinning liquid outward as it leaves the nozzle, so droplets concentrate in a thin, ring-shaped shell around the outside of the cone while the center stays largely free of liquid. A full cone nozzle, such as Jeltecn’s BB/BBG vaned series, routes liquid through internal vanes or a core insert that splits and redirects flow to fill the entire cross-section evenly. That structural difference, ring versus filled circle, is the reason the two patterns suit such different applications even though both start from a “cone” spray classification.
The swirl that creates the hollow cone’s ring pattern also does something else: it adds rotational energy to the liquid sheet, which breaks it into finer droplets than the more direct flow path inside a full cone nozzle at the same pressure. This is why hollow cone nozzles are the default choice whenever fine atomization matters, and full cone nozzles are the default choice whenever uniform, complete coverage matters.
If you have an unlabeled nozzle in hand and need to identify which pattern it produces, a quick bench test tells you immediately: run it at a moderate pressure onto a flat, dry surface such as cardboard or a test panel and observe the wetted pattern. A full cone nozzle wets the entire circle or square evenly, while a hollow cone nozzle leaves a visibly dry or lightly wetted center with a distinct ring of heavier wetting around the perimeter. This simple test is worth running whenever nozzles have been removed from their original packaging or labeling and mixed together during maintenance, since installing the wrong pattern in a header can silently reduce process performance without triggering an obvious fault.
Side-by-Side Comparison
| Factor | Hollow Cone Nozzle | Full Cone Nozzle |
|---|---|---|
| Spray cross-section | Ring / annular, empty center | Fully filled circle or square |
| Droplet size at equal pressure | Finer | Coarser |
| Coverage uniformity | Lower in the center of the target | High, even across the full area |
| Best liquid type | Clean to lightly filtered | Clean or lightly filtered; more tolerant of some solids in vaned designs |
| Typical duty | Gas scrubbing, cooling, fine misting, humidification | Washing, coating, cooling of solids, dust suppression over an area |
| Gas-liquid contact area | High for the liquid volume used | Lower per unit volume than hollow cone |
Worked Scenario 1: Flue Gas Cooling Ahead of a Scrubber
A flue gas conditioning tower needs to cool hot gas quickly before it reaches a downstream scrubber or baghouse, and duct length is limited. Fast evaporation matters more than filling every inch of the duct cross-section with liquid, since the gas itself is moving through and mixing with the spray. A hollow cone nozzle is the clear starting point here, since its finer droplets present more surface area per unit of liquid and evaporate faster, cooling the gas within a shorter duct run than a full cone nozzle would need at the same flow.
Worked Scenario 2: Washing a Conveyor or Parts-Washing Tunnel
A parts-washing tunnel needs even, predictable coverage across the full width of a conveyor, with no gaps that let contamination pass through untouched. Here, coverage uniformity is the dominant requirement, and the empty center of a hollow cone pattern would leave a gap unless nozzles were spaced unusually close together. A full cone nozzle, or a flat fan nozzle depending on the geometry, is the better starting point; see our full cone spray nozzle guide for sizing details.
Worked Scenario 3: Fine Mist Humidification in a Textile Plant
A textile finishing area needs to raise ambient humidity without leaving visible moisture on fabric or flooring. Fine, quickly evaporating droplets are essential, and the treated area is large enough that the ring pattern from several hollow cone nozzles overlaps into effectively continuous coverage. A hollow cone nozzle, or an air atomizing nozzle if compressed air is already available, is the better starting point over a full cone design, which would put more liquid into the air than the space can absorb before it settles.
Worked Scenario 4: Cooling a Moving Steel or Glass Surface
A rolling mill or glass line needs to cool a moving solid surface evenly across its full width, and any untreated strip left uncooled by an empty spray center would show up as a defect or a hot spot. A full cone nozzle, arranged in a header with overlapping patterns, is the standard choice; see Flat Fan vs Full Cone Nozzle for how these compare against flat fan alternatives in cooling duty.
Worked Scenario 5: Dust Suppression at an Enclosed Transfer Point
A conveyor transfer point needs to knock down airborne dust without oversaturating the material or the surrounding floor. A fine, well-atomized mist wets fine particles more effectively per liter of water than a coarser spray, which favors a hollow cone or ultrasonic misting design. If the water source carries sediment, however, clog resistance becomes the priority, and a spiral nozzle may be a more practical starting point than either cone design.
When the Choice Isn’t Obvious
Some applications sit in a gray zone: a process that wants finer droplets but still needs to avoid an untreated gap in the middle of the target, or a coverage-driven application where finer atomization would still be a bonus. In these cases, consider whether you can compensate for a hollow cone nozzle’s empty center through nozzle spacing and overlap, or whether the coverage gap is a hard constraint that rules it out. If distribution precision and center coverage matter at all, default to a full cone nozzle and evaluate whether a finer full cone model or a higher operating pressure gets close enough to the droplet size you want. If you are still unsure, share your target geometry, required droplet size, and coverage tolerance with Jeltecn’s engineering team for a specific recommendation.
Materials, Pressure Range and Thread Compatibility
Beyond spray pattern, hollow cone and full cone nozzles are generally available in the same range of materials, including 303SS, 316SS, brass, and PVDF for corrosive service, so material selection rarely decides between the two designs. Pressure range is a more meaningful difference: hollow cone nozzles typically show a bigger shift in droplet size across their rated pressure range than full cone nozzles do, since pressure directly intensifies the swirl. If your process needs to fine-tune droplet size without changing nozzles, a hollow cone design gives you more adjustment headroom within its rated range. Thread size and connection standards (NPT, BSPT, male or female) are typically interchangeable between the two designs at a given flow capacity, so header piping does not usually need to change if you switch pattern types during the selection process.
Common Mistakes When Choosing Between the Two
- Assuming “cone” means the same coverage. Both are marketed as cone nozzles, which leads some buyers to assume similar coverage. Always check whether the spec sheet or drawing shows a ring or a filled pattern before ordering.
- Sizing hollow cone spacing like full cone spacing. Because hollow cone nozzles leave an empty center, header spacing calculated for full cone overlap will usually leave gaps; recalculate overlap specifically for the ring pattern’s actual coverage diagram.
- Ignoring droplet size in scrubbing duty. Selecting a full cone nozzle purely for its higher flow capacity in a scrubbing application can under-deliver on absorption efficiency if the coarser droplets do not provide enough gas-liquid contact area.
- Overlooking pressure-driven droplet size changes. Assuming droplet size is fixed once a nozzle model is chosen ignores the meaningful shift available by adjusting pressure within the rated range, particularly for hollow cone designs.
Confirming Your Choice Before You Order
Before finalizing a purchase order, verify the following against your process requirements and the manufacturer’s data sheet:
- Required droplet size range and whether it must be adjustable via pressure
- Whether the target area’s center must receive direct spray coverage
- Liquid cleanliness and expected solids content
- Available pressure and flow at the nozzle, not at the pump discharge
- Header spacing and overlap calculated for the specific pattern type you select
- Material compatibility with the liquid’s chemistry and operating temperature
Jeltecn’s engineering team can review your application against both designs and recommend the better starting point, or suggest a mixed-pattern layout if your process would benefit from both.
Frequently Asked Questions
Can a full cone nozzle be adjusted to behave like a hollow cone nozzle?
No. The internal geometry that fills the center of a full cone spray is fixed by the vane or core design; you cannot convert one pattern into the other by changing pressure alone. If you need a hollow cone pattern, specify a hollow cone model.
Which nozzle gives finer droplets, hollow cone or full cone?
At equal pressure and flow, a hollow cone nozzle produces finer droplets than a full cone nozzle, because the swirl chamber that creates the ring pattern also adds rotational energy that breaks up the liquid sheet more thoroughly.
Can I mix hollow cone and full cone nozzles on the same header?
Yes, in some designs this is intentional, for example alternating patterns to blend fine atomization with center coverage. Confirm the combined coverage map with your nozzle supplier before finalizing a mixed layout.
Is a hollow cone nozzle more prone to clogging than a full cone nozzle?
Both vaned full cone and swirl-chamber hollow cone nozzles have a similar sensitivity to solids, since both rely on a relatively narrow internal passage. For liquids with meaningful solids content, an open-channel spiral nozzle resists clogging better than either design.
Which nozzle is better for gas scrubbing, hollow cone or full cone?
Hollow cone nozzles are generally preferred for gas scrubbing and absorption because their finer droplet spectrum and ring-shaped distribution maximize gas-liquid contact area for the liquid volume used. Full cone nozzles are still used in scrubbing where a coarser spray and higher flow capacity are needed.
Does a hollow cone nozzle waste liquid by leaving the center empty?
No. The liquid is simply concentrated where it does the most good for gas-liquid contact or fine misting duty; it is not wasted, just distributed differently than a full cone pattern. For applications that need center coverage, a full cone nozzle uses the same liquid volume more effectively.
How do I convert an existing full cone header to hollow cone nozzles?
In most cases the connection size and thread stay the same, so the header itself may not need modification, but you must recheck nozzle spacing and overlap since hollow cone coverage diagrams differ from full cone diagrams at the same mounting height. Confirm with a coverage test before committing to a full header changeover.
Get a Selection Recommendation
Tell us about your target geometry, required droplet size, and coverage tolerance, and we will help you decide between a hollow cone nozzle and a full cone nozzle. Contact our engineering team, or read the complete Hollow Cone Nozzle Guide and Full Cone Spray Nozzle Guide for detailed specifications.