SEAL-RING 4442269 - Caterpillar

A new tightening procedure for the stick cylinder piston locknut is available on the machines listed above. The new procedure applies a new tightening method for the locknut. The new procedure also removes the use of molybdenum grease on the threads of the rod and locknut.This tightening procedure is adaptable to the first production of the machines that are listed above.Refer to the following procedure to tighten the stick cylinder piston locknut.Stick Cylinder Piston Locknut Tightening Procedure
Illustration 1 g06094068
Piston and locknut location on stick cylinder rod
(1) Stick cylinder rod
(2) Piston
(3) Locknut
Remove locknut (3) and piston (2) from stick cylinder rod (1). Refer to Illustration 1.
Illustration 2 g06094113
Piston face locations
(2) Piston
(A) Piston Faces
Illustration 3 g06094159
Locknut face location
(3) Locknut
(B) Locknut face
Thoroughly clean piston faces (A) and locknut face (B) using alcohol or degreaser with a lint free cloth. Refer to Illustrations 2 and 3 for the face locations.
Illustration 4 g06094055
Rod face and thread locations
(1) Stick cylinder rod
(C) Rod face
(D) Rod threads
Thoroughly clean threads (D) and rod face (C) of rod (1) using alcohol or degreaser. Refer to Illustration 4.
Reinstall piston (2) onto stick cylinder rod (1).
Illustration 5 g06094132
Locations not to apply oil
View A-A is section of stick cylinder rod
(1) Stick cylinder rod
(2) Piston
(3) Locknut
(E) Contact area
(F) Contact area
Apply hydraulic oil to threads (D) of stick cylinder rod (1). Do not apply oil to the piston or locknut face in contact area (E) and (F), refer to Illustration 5.
Install locknut (3) and pre torque to 1500 N m (1106.3 lb ft).
Illustration 6 g06094142
Side view of stick cylinder rod
(1) Stick cylinder rod
(2) Piston
(3) Locknut
(G) Torque reference line
(H) Torque reference line
(J) Torque reference line
(K) Torque reference line
Use a paint pen to mark the face of locknut (3) to create torque reference line (G). Create another torque reference line (J) on stick cylinder rod (1). Ensure reference lines (G) and (J) are aligned. Refer to Illustration 6.
Use a paint pen to mark the face of locknut (3) to create torque reference line (H). Create another torque reference line (K) on stick cylinder rod (1). Ensure reference lines (H) and (K) are aligned. Refer to Illustration 6.Note: The reference lines are used to establish the 60 5 degrees turn that is used to achieve the desired clamp load.
Illustration 7 g06094148
Side view of stick cylinder rod
(1) Stick cylinder rod
(2) Piston
(3) Locknut
(G) Torque reference line
(H) Torque reference line
(J) Torque reference line
(K) Torque reference line
Apply the final torque by tightening locknut (3) until reference line (G) on locknut (3) is aligned with reference line (K) on rod face (1), refer to Illustration 7. Once aligned, ensure that the final torque is within the range of 17500 2500 N m (12907.3 1843.9 lb ft). If the final torque is below 15000 N m (11063.4 lb ft) after aligning the reference lines, stop and remove the locknut. Inspect the locknut for burrs, improper pre torque value, or any thread deformation. If the final torque is above 20000 N m (14751 lb ft) before aligning the reference lines, stop and remove the locknut. Inspect the