tips fig9 is a schematic side view of a thermomechanical tmp refiner system 60 such as is described in us patent application publication 2006 0006265 entitled u201c high intensity refiner plate with inner fiberizing zone u201d a chip feed system 62 steams the wood chips and applies a pressure to the slurry of steamed wood chips a steaming vessel 64 may be used to steam the chips at high pressure wherein high pressure steam is introduced to the steaming vessel the chip feed slurry may be at a high pressure of for example 15 to 25 psig pounds per square inch gauge the high pressure chip feed slurry is fed via a high pressure chip feed tube 65 to a high consistency primary refiner 66 that has relatively rotating disks the disks are housed in a casing 68 of the primary refiner 66 a pair of disk oppose each other in the casing such that the array of stator plates face the array of rotor plates and both arrays are coaxial a narrow gap separates the bars of the stator plate and bars of the rotor plate the casing is operated at a high pressure e g 1 to 6 bar for tmp and 6 to 8 bar to mdf a refiner feed device 71 such as a ribbon.