FRAME AS-N/ENG 2Q4099 - Caterpillar

(G) Measurement of Roller Frame Twist
(1) Put short straight-edge (4) on each roller mounting pad as shown. Measure the alignment of each pad, respective to the rear roller mounting pad. The location and amount of twist in a roller frame can be found with this procedure. The maximum difference of each roller mounting from the reference surface should not be more than one turn of the knurled nut. Make a record of the measurements on a data sheet.(H) Measurement of Diagonal Brace Vertical Alignment
(1) Install centering tool (5) in the roller frame as shown. Put level (3) on the shaft of the centering tool and measure the out of alignment dimension, respective to the roller mounting. The diagonal brace should not be out of alignment more than one-half turn of the knurled nut, or 3.6 mm/m (.043" per 12.0"). If the dimension is more than permissible, it is probable that the diagonal brace is bent. However, it is possible that the outer box section is bent down; check for this condition with the 2133 (84") straight-edge.(J) Measurement of Twist in Bearing Bore of Diagonal Brace
(1) Put short straight-edge (4) through the bearing bore. Put level (3) on the straight-edge and measure the amount of twist in the diagonal brace bearing bore, respective to the shaft of the centering tool shown in item (H). The bearing bore should not be out of alignment more than one-quarter turn of the knurled nut, or 1.8 mm/m (.022" per 12.0").(K) Measurement of Idler Support Box Section - Vertical Alignment
(1) Put short straight-edge (4) on the lower surface of the support as shown. Put level (3) on the straight-edge to measure the alignment of the idler support surface, respective to the rear roller mounting. The parallel alignment of the idler supports should be within one turn of the knurled nut, or 7.2 mm/m (.086" per 12.0"), respective to the reference surface. Make a record of the measurements on a data sheet.(L) Measurement of Roller Frame for Straightness
(1) Put straight-edge (2) on the surface of the roller mountings as shown. Check to see if all surfaces are flat and in line. If they are not, measure the difference and make a record of the measurement on a data sheet. The maximum difference in straightness should be no more than 6.4 (.25").(2) Install bolts in all roller mounting pads. Put straight-edge (2) on the bolts as shown to check the centerline of the bolt holes. The centerline of the bolt holes should be in alignment within 1.5 (.060"). If the tolerance is above this dimension, the roller frame is bent either in or out. Make a record of the measurements on a data sheet.Procedure For Straightening Roller Frames
Two different procedures are given in the following instruction for straightening the roller frame. The heat and cool procedure can be used for straightening frames in the field or in small repair shops. The hydraulic press procedure is practical for use in large undercarriage rebuild shops where a