Pivotal door for adjusting the position of and gaining access to a grinding roller of a pulverizer mill

A mill door opening mechanism for a grinding mill, the door opening mechanism comprising:

• a door assembly configured to pivot with a journal having a grinding roller in communication therewith,
• the door assembly configured to be split into an upper door assembly and a lower door, the upper door assembly pivotal with the journal with the grinding roller mounted thereon;
• the journal is fixed to a journal head which is pivotally connected to a portion of the grinding mill,
• the journal head comprising a shaft receiving hub aligned along a longitudinal axis thereof,
• a trunnion shaft is mounted in the hub and projects outwardly therefrom and into an eccentric trunnion bushing housing, wherein the trunnion bushing housing has a flange extending radially outward from an outboard end thereof, the flange is adjustably secured to the portion of the grinding mill,
• a lever arm fixed to the flange;
• and
• an actuator connected between the lever arm and a mill wall of the grinding mill, the actuator is configured to pivot the upper door assembly and the lower door together about the longitudinal axis and between a closed position and an open position.

A grinding roller adjustment mechanism for a grinding mill, the grinding roller adjustment mechanism comprising:

• an upper door assembly pivotally arranged to the grinding mill, a journal having a grinding roller mounted thereon, the journal is fixed to a journal head pivotally connected to a portion of the grinding mill,
• the journal head comprising a shaft receiving hub aligned along a longitudinal axis thereof, and a trunnion shaft mounted in the hub and projecting outwardly therefrom and into an eccentric trunnion bushing housing, wherein the trunnion bushing housing has a flange extending radially outward from an outboard end thereof, the flange is adjustably secured to the portion of the grinding mill,
• a lever arm fixed to the flange;
• and
• an actuator connected between the lever arm and a mill wall of the grinding mill, the actuator is configured to rotate the trunnion bushing housing to thereby change the position of the longitudinal axis while the upper door assembly is closed, to control the location of the grinding roller relative to a grinding ring disposed in the grinding mill.