Sprayer Depot Blog

Contributed by guest blogger:  Mark Techler, Techler & Associates

What is a fitting?

A fitting is a component that connects pipe, hose, tubing, etc. Most hardware stores sell general fittings for things like residential plumbing, irrigation, etc. Sprayer fittings for use on agricultural, turf and pest control sprayers are unique and should be ordered directly from Sprayer Depot.

There are 4 basic things you need to know about fittings:

COMMON CONNECTIONS                                                                                                                                            Fittings can have male or female threaded connections. In the USA we use NPT (National Pipe Threads) which are tapered and need Teflon tape or pipe dope to seal. Common NPT fittings for sprayers are 1/8” to 3”. The nominal pipe size is loosely related to the inside diameter of Schedule 40 pipe, so you will generally not find any measured dimension on pipe or fittings that exactly matches the nominal size. As the “Schedule” number goes up, the wall thickness of pipe increases but the outside diameter does not.

Fittings can have hose barb connections. Hose is forced over the barb and sealed with a hose clamp. The nominal size of hose is the inside diameter, so the largest diameter of a hose barb is slightly larger than the nominal size of the hose barb. For instance, you will not find a ¼ inch dimension measurement on a ¼ inch hose barb.

COMMON CONFIGURATIONS
There are many fitting configurations.  The most common include:                  

• Adapters have different connections on the ends,  such as male NPT to hose barb

• Elbows change the direction of flow 90 degrees; A “street” elbow is male NPT by female NPT

• Reducer Bushings have a larger male NPT and a smaller female NPT for reducing the pipe size

• Nipples have 2 male NPT connections of one size, like a piece of threaded pipe

• Tees are three way connections

• Crosses are four way connections   

• Plugs stop flow

COMMON MATERIALS

Plastic fittings are generally rated at 150 psi max pressure at ambient temperature Nylon fittings have greater strength but lower corrosion resistance while polypropylene fittings have less strength but will resist corrosion from strong acids, fertilizer (with nitric, phosphoric, or sulfuric acid), and bleach. Steel is an inexpensive way to handle higher pressures, but is the least corrosion resistant material. Brass is widely used for higher pressures, is corrosion resistant to many ag chemicals, and also cost effective. Stainless steel is the premium metal choice for best corrosion resistance and higher pressures.   

 OTHER FITTINGS

Other fittings include cam and groove couplings, which are commonly used with low pressure liquid transfer. Nozzle bodies, which hold ag spray nozzles in place, are available for direct mounting on the pipe that carries the liquid (wet boom) or with hose barb connections (dry boom). Fly-nut fittings are commonly used for ag diaphragm pumps.

Not sure which fitting you need?  Our Customer Service Technicians can help.  Call 800-228-2905 weekdays 8:00am - 5:30pm or CLICK HERE to chat live on our website.