D2 Tool Steel in Extruder

Hello! I am relatively new to the extrusion world and looking for more information on the use of D2 Tool Steel for food contact surfaces in this type of process. We produce bulk RTE nutritional cereals that are used by our customers in various retail products. I have been told that the different food contact zones are coated in 3 different ways, one being powder cast. The surfaces all appear to rust and they wire wheel them when visible. We have discovered two separate areas on the extrusion screws that are significantly chipped and there is now a crack on the coated food contact surface of the barrel... These are all red flags to me. I have placed the equipment on hold but production obviously wants me to remove that tag! Thank you for your help!