Performance of the 1-meter models of the 70 mm aperture quadrupole for the LHC low-beta insertions

Following the successful testing of the first 1-metre model of the 70 mm aperture quadrupole for the LHC low-beta insertions, two further 1-metre magnets have been built. All magnets feature a four-layer coil wound from two 8.2 mm wide graded NbTi cables and a four-way split yoke supporting structure. In this paper we review the training history of the three magnets performed at 4.3 K and 1.9 K in several tests. All magnets surpassed the operating gradient required for the LHC, with the third magnet reaching 260 T/m, its short-sample gradient at 1.9 K. The peak temperatures in the superconductor at various operating conditions are reported and a summary of magnetic field measurements is given.