Method for monitoring physical conditions of a roller crusher, and a refitting kit for a roller crusher

A method for monitoring the physical condition of a deflection distributor of a roller crusher, wherein said deflection distributor includes a deflection distributing shaft, thrust rods each having first and second ends and mounts for attachment of said deflection distributing shaft at a first and a second side of a frame of said roller crusher, wherein a first end of each of said thrust rods is attached to said deflection distributing shaft via a lever, wherein a second end of each of said thrust rods is attached to a movable bearing housing of said roller crusher, the method comprising:

• providing at least one load sensor configured to detect material load in the deflection distributor;
• providing at least one positioning sensor configured to detect a parameter pertaining to a distance between a first point and a second point of the roller crusher, wherein at least the first point is defined on the deflection distributor or on one of the movable bearing housings;
• displacing the movable bearing housings with respect to each other such that the deflection distributor is moved from a first identified rigid state at which joint clearance does not affect the deflection distributor, via an intermediate state at which joint clearance affect the deflection distributor, to a second identified rigid state at which joint clearance does not affect the deflection distributor;
• and
• determining, based on output from the at least one positioning sensor obtained at the first and the second rigid states, respectively, a displacement distance indicative of a degree of joint clearance in the deflection distributor.