My freezer is making this high pitch noise, its an industrial Beaufort freezer on wheels

Zaria:
I have the same kind of fridge and it also makes this kind of noises, however, they are on the acceptable level. They sound more like a seal being happy with the new food. It is not all the time but sometimes. I think it is the contraction and expansion of the pipes that cause the noise and is not a sign of any problem. Of course all depends on the level of the noise you have...
Hope it helps. Greg.