Calpeda 14012130000 Impeller Nut - M10 x 1 Stainless
The Calpeda 14012130000 is the genuine stainless impeller nut, an M10 x 1 fine pitch hexagon nut 5 mm high with a 17 mm across-flats hexagon, made to UNI 5590. It is the fastener at the very end of the pump shaft that holds the impeller hard against its shoulder, and it is the last thing to go on when a wet end is rebuilt and the first thing to come off when it is opened.
The 17 mm across-flats dimension is worth noting because it is not what most people expect from an M10 nut. A standard M10 hexagon takes a 17 mm spanner too in the metric coarse series, but this is a thin nut in fine pitch, so a spanner that fits does not prove the nut is right - the thread and the height still have to match. Get in the habit of checking the pitch, not the spanner. It is also the reason a substitute picked out of a bin because it screwed on a couple of turns can strip the shaft thread under load.
Stainless is specified because the nut sits permanently in the pumped liquid at the least accessible point of the assembly. When one corrodes in place the usual outcome is a rounded hexagon and a seized thread, and freeing it risks the shaft end that everything else locates from. The sensible habit is to fit a new nut whenever the impeller comes off rather than reusing one that has already been rounded slightly by a previous removal. Assemble on clean threads, use a proper six-point socket or ring spanner rather than an adjustable, and tighten firmly and steadily.
Key Features
- Genuine Calpeda spare part
- Stainless steel construction for permanently submerged service
- M10 x 1 fine pitch thread
- 17 mm across flats, 5 mm high, to UNI 5590
- Clamps the impeller against its shaft shoulder and holds it against hydraulic thrust
- Replaces a nut that has been rounded or corroded, protecting the shaft thread
Applications
- Calpeda centrifugal pumps using an M10 x 1 impeller nut
- Impeller replacement, mechanical seal work and wet-end overhaul
- Replacing a corroded, seized or rounded impeller nut
- Seawater, brackish water and aggressive liquid duties
- Workshop spares stock and rebuild kits
- Marine, dockside, industrial and agricultural pump service
Specifications
- Brand: Calpeda
- Manufacturer: Calpeda Spa
- Manufacturer Part Number: 14012130000
- Part Type: Impeller nut, hexagon
- Thread: M10 x 1 (fine pitch)
- Across Flats: 17 mm
- Nut Height: 5 mm
- Standard: UNI 5590
- Material: Stainless steel
- Condition: New
Frequently Asked Questions
Q: How can I check the pitch on my old nut before ordering?
A thread pitch gauge is the reliable way, and they cost very little. Failing that, count the threads over a measured 10 mm on the shaft - ten threads means a 1 mm pitch, which is what this nut needs.
Q: Is there usually a washer under it?
That varies between pump builds, so note exactly what comes off and in what order before anything is cleaned or set aside. Leaving out a washer changes how far the nut runs down and how the impeller is clamped.
Q: The nut spins but will not come off. What is happening?
Most often the impeller is turning with it because nothing is holding the shaft. Hold the shaft at its flats or at the motor fan end rather than gripping the impeller vanes, which are easily bent and are not designed to take that load.
Q: Can I reuse a nut that only looks slightly marked?
You can, but the flats are what you have to grip next time, and each removal rounds them a little further. Given how little the part costs against the work involved in reaching it, fitting a fresh one is the better habit.
Not sure this is the right part? Send us a Picture of the pump plate on your pump and the CLR Marine team will confirm the correct impeller nut before you order.
CLRMarine
