Pin puller assembly and methods

A column assembly for use in a pin puller assembly, the pin puller assembly being operable to pull a pin from a machine, the machine having a frame supporting the pin, the pin puller assembly including a piston-cylinder unit including a cylinder having a first cylinder end and an opposite second cylinder end and defining an axis extending therebetween, the cylinder defining a chamber and having a port communicating with the chamber, and a piston defining an axial passage and having a piston end, the piston being movably supported by the cylinder, fluid passing through the port, causing movement of the piston relative to the cylinder, a pull rod positionable through the axial passage and having a first rod end positioned proximate the first cylinder end and a second rod end positioned proximate the second cylinder end, the second rod end being connectable to the pin to be pulled, and a reaction member engageable between the pull rod and the piston, the column assembly being positionable between the cylinder and the frame, the column assembly comprising:

• a first column member connectable to the cylinder and having a first length along the axis, and
• a second column member releasably lockable to the first column member and having a second length along the axis;
• wherein each of the first column member and the second column member has a cylinder end positionable toward the cylinder and an opposite frame end positionable toward the frame, and wherein a first locking member is proximate the frame end of the first column member and a second locking member is proximate the cylinder end of the second column member, the second locking member being engageable with the first locking member to releasably lock the second column member to the first column member.

A method of assembling a pin puller assembly to pull a pin from a machine, the machine having a frame supporting the pin, the method comprising:

• positioning a piston-cylinder unit relative to the frame, the piston-cylinder unit including a cylinder having a cylinder end facing toward the frame and defining a chamber and a port communicating with the chamber, and a piston movably supported by the cylinder, the piston defining an axial passage and having a piston end opposite the cylinder end, fluid passing through the port causing movement of the piston relative to the cylinder;
• positioning a pull rod through the axial passage;
• engaging an end of the pull rod with the pin to be pulled;
• engaging a reaction member on the pull rod;
• positioning the reaction member on the pull rod against the piston end;
• installing a column assembly between the cylinder end and the frame, installing including
• positioning a first column member against the cylinder end,
• locking a second column member to an opposite end of the first column member, and
• engaging an end of the second column member against the frame.