I think the simplest way to achieve this would be to use a ramdisk.
You can look this up on google but the idea is that some part of your filesystem is backed by RAM instead of an HDD. So loading from a file in this part of your filesystem would be loading from RAM directly.
That being said it sound weird that loading takes so long.
How big is your network? Is it really the torch.load call which is slow? Or something else?