Torque specifications for track shoe bolts. Description

Transcription

1 VN AS Issued Mauro ettini Approval Paolo iolchini :Revised 1. PURPOSE This specification define the assembly criteria and bolt torque to be applied on track shoe for clawer machine applications. 2. ASSEMLY PROCEDURE It is very important to fit the pads correctly. Incorrect fitting can cause loosening or loss of torque in screws. Use only new screws and nuts. Used screws, even though they appear in good condition, can become plastically deformed and do not ensure correct tightening. Remove any paint or oxidization from the pad fastening surface. Make sure there are no dents on the area itself and eliminate these if there are. Make sure the holes on the link are clean and that the screw can be freely fitted. Remove any paint or oxidization on the link nut seat. A.Track Shoe assembly position Single Grouser shoe Double Grouser shoe Assembly Direction Pin oss side Triple Grouser shoe Flat shoe Assembly Direction.Track Nut Position Pin oss side

2 VN AS Issued Mauro ettini Approval Paolo iolchini :Revised Square Nut Exagonal Nut Mail ox Nut.Procedure to tighten the The torques to be applied for each screw depend on the type of tightening selected: Final torque tightening Corner torque tightening Corner torque tightening is used to eliminate the various friction coefficients between the parties. For heavy-duty applications, the use of a corner torque is preferable. Final torque tightening Apply the tightening torque according to the diameter and the resistance class of the screw. Initially tighten with a wrench and reach the final torque using a specific torque measuring device. Always keep stringently to the figures shown on the following table. Corner Torque Tightening With this, the screws must be tightened with a first pre-torque as shown on the following table, always according to the diameter and screw class. After this first pre-setting turn the screw by 120 (1/3 turn) using a specific corner measuring device. With this, a specific plastic deformation of the screw can be achieved which ensures the maximum obtainable tightness. Re-Checking the torque Torque must be checked again after the firt 50 hours of use. Track Nut Correct position In both tightening s, follow the fitting sequence alongside.

3 VN AS Issued Mauro ettini Approval Paolo iolchini :Revised. 3. VALUES TO E USED FOR SCREW TIGHTENING WITHOUT UNDER HEAD WASHER Dimension Lbf-ft M10x1 100 ±5 32 ±2 74 ±4 24±1 M12x1 180 ±10 60 ±3 133 ±7 44 ±2 M14x1, ±15 95±5 207 ±10 70±4 M14X1,5 270 ±15 90 ±5 199 ±10 66 ±3 M16X1,5 400 ± ± ± ±7 M18X1,5 590 ±30 290± ± ±11 M19x1,5 710 ± ± ±26 258±13 M20x1,5 810± ± ± ±13 M22x1, ± ± ± ±15 M24x1, ± ± ± ±17 M27x1, ± ± ± ±25 M30X ± ± ± ±34 Dimension Lbf-ft 7/16" 20UNF 130 ±6 45 ±2 96 ±5 33±2 1/2" 20UNF 200 ±10 70 ±4 148 ±7 52 ±3 9/16" 18UNF 290 ±15 103±5 214 ±11 76 ±4 5/8" 18UNF 400 ± ± ± ±7 3/4" 16UNF 700 ±35 352± ± ±13 7/8" 14UNF 1130 ±55 395±20 834± ±15 1" 14UNS 1450 ± ± ±52 413±21 1 1/8" 12UNF 1990 ± ± ± ±30 1 1/4" 12UNF 2780 ± ± ± ±43

4 VN AS Issued Mauro ettini Approval Paolo iolchini :Revised 4. VALUES TO E USED TO TIGHTEN THE SCREWS WITH UNDER-HEAD WASHER Dimension Lbf-ft M18x1,5 690 ±35 340± ±25 251±13 M20x1,5 840 ±45 380± ±30 260±14 M22x1, ±55 425± ±42 313±16 M24x1, ±70 525± ±50 387±19 Dimension Lbf-ft 9/16" 18UNF 310 ± ±5 229 ±11 81±4 3/4" 16UNF 730 ±35 365± ± ±13

5 VN AS Issued Mauro ettini Approval Paolo iolchini :Revised 5. VALUES TO E USED TO TIGHTEN SPLIT-LINK SCREWS SCREWS WITHOUT UNDER-HEAD WASHER Dimension Lbf-ft M12x1 200 ± ±7 M14x1, ± ±12 M16X1,5 450 ±20 332±17 M19x1,5 760 ± ±28 M20x1,5 870± ±32 M24x ± ±48 M27x ± ±70 M30X ± ±161 Dimension Lbf-ft 1/2" 20UNF 240 ± ±9 9/16" 18UNF 330 ± ±12 5/8" 18UNF 450 ± ±17 3/4" 16UNF 750 ± ±28 7/8" 14UNF 1180±55 870±44 1" 14UNS 1550± ±57 1 1/8" 12UNF 2040 ± ±75 1 1/4" 12UNF 2850 ± ±105 SCREWS WITH UNDER-HEAD WASHER Dimension Lbf-ft M14x1, ± ±13 M16X1,5 480 ±20 354±18 M18x1,5 650±30 479±24 M19x1,5 800 ± ±30 M20x1,5 900± ±33 M22x1, ± ±46