More Flux

Resistive magnets, made of many stacked Bitter plates, are made by teams of skilled workers here at the Mag Lab. There's more info on how resistive magnets work here.

The 45-tesla hybrid magnet (so named because it's part resistive magnet, part superconducting magnet) is the most complex powered magnet maintained by our Magnet Science & Technology team. It's also the magnet most in demand by visiting researchers who use the lab's magnets.

We asked Resistive Magnet Shop technician Jim O'Reilly, who knows the hybrid perhaps better than anyone because he put it together, to provide some interesting details hybrid magnet's construction.

Measuring a bitter plate. Click for a larger image

In total, the hybrid is made of 3631 stacked plates and 285 insulators.
Those plates and insulators have a total of 880,000 holes.
There are 10,000 parts in the hybrid resistive coils.
Each coil takes about one week to stack, and there are five coils in the hybrid magnet.
Once the coils are stacked it takes only two days to assemble them, one inside the other, like Russian dolls.
Bitter plates range from 0.29 mm to 1 mm thick. Insulators are 0.15 mm thick.
To move the water necessary for cooling through the Bitter plates, resistive magnets utilize two pumps, each packing a whopping 500 horsepower.