ICE-Piston Preload Telemetry
The cryogenic ICE-PISTON preload cycle sets the magnets' mechanical baseline; its telemetry defines the reference every strain feature is measured against.
Preload as reference
Before the magnets carry field, the ICE-PISTON cryogenic preload cycle establishes a controlled mechanical clamp on the winding pack and structure. This preload is what lets the REBCO magnets withstand the Lorentz loads at 16.84 T in the breeder and 26.49 T at the burner's plugs. Its telemetry defines the mechanical baseline against which every operational strain is measured.
What the cycle reports
- Cryogenic temperatures through the preload sequence.
- Preload force or displacement as the piston sets the clamp.
- Resulting baseline strain across the magnet gauges.
- Cryostat thermal state, coupled to feedthrough heat leak.
Setting the strain baseline
When the preload completes, the fabric captures the strain state as the baseline for the strain-delta feature. This is why the delta isolates operational load: the static preload has already been subtracted. A preload that lands off-nominal changes the baseline, which the fabric records so later deltas remain meaningful.
A safety-relevant precondition
Because magnet mechanical integrity depends on correct preload, the preload telemetry is a go/no-go precondition, checked before high-field operation. It also enters the thermal budget the twin tracks, since the same cryogenic system cools the magnets and touches the diagnostic feedthroughs. The preload cycle is an engineering design specification for the FOAK machines under construction from Q2 2027.