Zoro Select 511-903BC Galvanized Hex Bushing 3 in MNPT x 1/2 in FNPT
Galvanised malleable-iron hex bushing reduces a 3 in male NPT pipe to a 1/2 in female NPT connection for Schedule 40 systems
- Product typePipes, Valves & Fittings
- Galvanized coating resists corrosion for long service life
- Malleable iron body handles Class 150 pressure rating
- 3 in MNPT to 1/2 in FNPT reduces pipe size
- Hex design allows secure wrench tightening during install
- Schedule 40 compatibility fits standard piping systems
Zoro Select Galvanized Hex Bushing
This Zoro Select galvanized hex bushing connects a 3-inch male NPT pipe to a 1/2-inch female NPT fitting. It is built from malleable iron with a Class 150 rating for Schedule 40 piping systems. The component suits plumbers and maintenance crews adapting pipe diameters in water, air or gas lines.
Malleable Iron Construction Handles Pressure
The galvanized malleable iron body resists corrosion and meets the Class 150 pressure rating for Schedule 40 service. Normal operating temperatures in plumbing or compressed-air circuits produce no audible noise from the fitting itself. Power draw is not applicable to this passive mechanical component.
Hex Flats Simplify Installation
External hex flats allow a standard wrench to tighten the joint without damaging the fitting. Male and female NPT threads seal with tape or compound for leak-free connections. The bushing reduces line size in a single step, saving space compared to a coupling and nipple combination.
How it compares
Measured against everything we stock in Bath Accessories & Soap Dispensers, at today’s prices. Recalculated every night.
- Price $14.99
- Cheaper than about 80% of the 1,499 comparable items (median $39.99).
Specifications
| Product | |
|---|---|
| Brand name | ZORO SELECT |
| Product type | Pipes, Valves & Fittings |
Questions about this item
How do I install a 3 in MNPT hex bushing into a Schedule 40 pipe without cross-threading?
Clean both NPT threads, apply PTFE tape or pipe dope to the male side only, hand-tighten the 3 in MNPT end into the female fitting, then use a hex wrench on the bushing flats for one to two extra turns; stop when resistance spikes to avoid stripping the 1/2 in FNPT port.
What maintenance will the galvanized malleable iron bushing need over time?
Inspect the zinc coating annually for white rust or pitting; if the galvanizing wears through on the 3 in MNPT or 1/2 in FNPT threads, replace the fitting — malleable iron cannot be re-galvanized in place.
What pressure limit appears first on a Class 150 bushing under sustained steam service?
The Class 150 rating caps continuous non-shock pressure at 150 psi; sustained steam at higher pressure will exceed the malleable iron body limit before the Schedule 40 pipe wall becomes critical.
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