Airblast nozzle bodies

If you are considering switching from disc & core combination nozzles to single-piece moulded nozzles (and I encourage you to do so), you need to know if they will fit your existing nozzle bodies.

A typical brass roll-over style dual nozzle body with Cap and optional check valve.

A typical brass roll-over style dual nozzle body with Cap and optional check valve.

Many sprayers use roll-over, dual nozzle bodies so two nozzles can be mounted in each position for quick-changes from dilute to concentrated applications, or to change the spray distribution from block to block. However, some sprayers (like Turbomist) employ single nozzle bodies. Their technique is double the density of the bodies on the boom, arranged in an alternating A-B pattern. By shutting off each alternate nozzle you can use the A’s or the B’s. This gives the added flexibility to “double-up” in positions along the boom where more spray is required. This strategy isn’t ideal, but in a pinch…

Some sprayers do not use roll-over nozzle bodies. Instead, they double the density of the bodies on the boom for use in an alternating A-B pattern.

Some sprayers do not use roll-over nozzle bodies. Instead, they double the density of the bodies on the boom for use in an alternating A-B pattern.

If your sprayer has roll-over bodies already, you’ll want to check the diameter of the body outlet (where the nozzles rests) and the outlet cap (which secures the nozzle tightly against the body outlet). Check to see if your sprayer uses an unusual diameter nozzle, like older FMC disc & whirls or the older European large-diameter pink ceramic disc & cores. Moulded nozzles won’t fit in those bodies, so you’ll need to replace them.

At this time, the decision to replace nozzle bodies will cost about $50.00 CAD per body. Be aware of the following options and considerations:

  • In North America, you might encounter four inlet thread types: NPT, BSPT, NPS and BSPP. The inlet thread sizes are 1/4” female, 1/4” male and 3/8” male. 1/4” female is not available on the NPS or BSPP inlet thread types.
  • Old FMC with nozzles bodies that do not have check valves. Once the pressure is off, the booms begin to drain through the lowest nozzle. This is a waste of pesticide and unnecessary environmental contamination.

    Old FMC with nozzles bodies that do not have check valves. Once the pressure is off, the booms begin to drain through the lowest nozzle. This is a waste of pesticide and unnecessary environmental contamination.

    The roll-over feature allows you to turn off the nozzle, but it also allows you to reposition the tip +/- 15° from centre. Be aware that moulded nozzles protrude and may hit the edge of the sprayer duct when they are turned. Ensure they’ll clear any possible obstructions.

  • Make sure the bodies you get have diaphragm check valves. They are an option well worth having to prevent the boom from draining when not spraying and improving on-off reaction time. In my opinion, they should be mandatory. If your sprayer doesn’t have them, consider purchasing mesh nozzle strainers with built-in ball valves. You have to be very diligent to keep them clean, but they work well as an alternative to check valves.
  • Nozzle bodies have either single or double outlets. The doubles are very convenient because they allow you to switch between two nozzles quickly and easily. Again, ensure they’ll clear any obstructions with the nozzle installed.
  • Nozzle bodies DO NOT come with the nozzle caps – you have to order them separately. This was an unpleasant surprise the first time I ordered a set. The standard caps are brass hex nut-style but there are also nylon wing-style caps that don’t require a wrench.

Be aware, North American nozzle caps might not fit some European sprayers, like the LipCo.

Old FMC roll-over bodies removed in favour of moulded-nozzle-compatible roll-overs with check valves.

Old FMC roll-over bodies removed in favour of moulded-nozzle-compatible roll-overs with check valves.

National, Pipe Tapered (NPT) single-sided, brass roll-over nozzle body with check valve. Note the shallow cap pictured here.

National, Pipe Tapered (NPT) single-sided, brass roll-over nozzle body with check valve. Note the shallow cap pictured here.

British Standard, Pipe Tapered (BSPT) single-sided, brass roll-over nozzle body with a check valve.

British Standard, Pipe Tapered (BSPT) single-sided, brass roll-over nozzle body with a check valve.

National, Pipe Straight (NPS) single-sided, brass roll-over nozzle body with check valve. Note the deep cap pictured here.

National, Pipe Straight (NPS) single-sided, brass roll-over nozzle body with check valve. Note the deep cap pictured here.

British Standard, Pipe Parallel (BSPP) single-sided, brass roll-over nozzle body with a check valve.

British Standard, Pipe Parallel (BSPP) single-sided, brass roll-over nozzle body with a check valve.

Regarding the cap depths, sprayer operators may be using an optional gasket between the cap and the tip, and hopefully are using strainers between the tip and the body. Those take up room, so a deeper cap may be required. Another reason is because of the nozzle shoulder. For example, TeeJet sells an A and a B option for each moulded hollow cone tip. The B style has a thick shoulder, similar to HyPro-Albuz moulded nozzles. If you have tips with thick (B) shoulders, shallow caps may not thread onto the body outlet. Alternately, if you have a deep cap and a nozzle with thin (A) shoulders, the cap will be completely tightened but will not compress the shoulder against the body outlet to form a seal; spray will escape around the loose nozzle.

Older nozzle bodies can seize in the boom, requiring novel approaches to removing them. In this case, the mechanic is heating the fittings before unscrewing them. I took this picture with a zoom lens so avoid getting too close! If you plan to do this, please be very careful to do so in an open space, using PPE like gloves and a respirator. Years of residue build-up should be anticipated and respected.

Older nozzle bodies can seize in the boom, requiring novel approaches to removing them. In this case, the mechanic is heating the fittings before unscrewing them. I took this picture with a zoom lens so avoid getting too close! If you plan to do this, please be very careful to do so in an open space, using PPE like gloves and a respirator. Years of residue build-up should be anticipated and respected.

Moulded hollow cone nozzles come in the thin shoulder (A-style) or thick shoulder (B-style) varieties. The B-style is the ISO standard and is preferred.

Moulded hollow cone nozzles come in the thin shoulder (A-style) or thick shoulder (B-style) varieties. The B-style is the ISO standard and is preferred.

In an effort to clear up some of the complication, TeeJet now sells the TXR line of hollow cone tips, which meet all ISO standards, including colour coding and the thicker (B) shoulder. They are my preferred TeeJet-brand hollow cone tip if you are considering moulded hollow cones for the first time – don’t go back to their older styles which do not meet ISO standards. If you can find them in North America, Albuz are a great alternative, but presently are more common in Europe.

No matter which moulded nozzle, nozzle body and cap combination you choose, there’s always the possibility for incompatibility. I suggest getting one of each before buying a whole set to ensure there are no issues.