A cold box for the forced cooling systems of superconducting magnets

A cold box, which does not have temperature expanders, designed for a forced cooling system is described. The cold box can be used to maintain superconducting magnets at 4.5 − + 5 K for a long period of time. Tests on the cold box have shown that the mass flow rate of forced cooling flow is 6 + − 10 kg h −1. For this flow rate, 1.1 – 1.3 kg h −1 of liquid He from the transport dewar is required.