25 minute read
G Boom Telescoping System
Contents
G-1 Boom (Three-Section Boom)..........1
1. Structure...................................................1
2. Top Slide Plate Installation Procedure.......4
3. Adjustment of Clearance between Boom Sections........................................4
4. Telescoping wire rope adjusting procedure..5
5. Telescoping wire rope readjusting procedure ......................................................6
G-2 Boom (Four-Section Boom)............8
1. Structure...................................................8
2. Notes for Reassembly...............................9
3. Boom Adjustment Procedures.................10
3.1 Top Slide Plate Installation Procedure......10
3.2 Adjustment of Clearance between Boom Sections..............................................10
G-3 Boom (Five-Section Boom)...........12
1. Structure.................................................12
2. Notes for Reassembly.............................13
3. Boom Adjustment Procedures.................14
3.1 Top Slide Plate Installation Procedure......14
G-4 Telescoping cylinder (Three sections boom)......................................16
1. Structure.................................................16
2. Notes for Reassembly of Cylinder Assembly ....................................................17
3. Notes for Reassembly of Telescoping Cylinder .......................................18
G-5 Telescoping Cylinder (Four-Section Boom).....................................19
1. Structure.................................................19
2. Description of Operation..........................22
2.1 Control of Telescoping Sequence.............22
2.2 Shock-Absorbing Mechanism of No. 2 Cylinder...............................................23
3. Notes for Reassembly of Cylinder Assembly ....................................................24
4. Notes for Reassembly of Telescoping Cylinder .......................................25
5. Cautions about Telescoping Wire Rope Adjustment..................................27
6. Telescoping Wire Rope Adjustment Procedure....................................27
6.1 Wire rope adjustment with the telescoping cylinder out of the boom.....................27
6.2 Wire rope adjustment with the telescoping cylinder installed in the boom.............29
G-6 Telescoping Cylinder (Five-Section Boom).....................................30
1. Structure.................................................30
2. Description of Operation.........................33
2.1 Control of Telescoping Sequence.............33
2.2 Shock-Absorbing Mechanism of No. 3 Cylinder..............................................36
3. Notes for Reassembly of Cylinder Assembly ....................................................37
4. Notes for Reassembly of Telescoping Cylinder .......................................39
5. Telescoping Wire Rope Adjustment Procedure....................................41
5.1 Wire rope adjustment with the telescoping cylinder out of the boom.....................41
5.2 Wire rope adjustment with the telescoping cylinder installed in the boom.............42
1. Structure.................................................44
(Three-Section Boom)
There is a case that the appearance and so on differ from the parts for this machine. Although there is not so much difference in functions and disassembly procedures, make sure of the serial number of this machine and the parts sales unit described in the parts catalog before starting disassembling operations.
Notes for Reassembly
1. Apply grease to the boom inside surfaces that rub against slide plates.
2. Press-fit the plain bearings at the base of the boom with their grease grooves on the outside.
3. Bend down the plate on the boom elevating cylinder pivot pin after installing the bolts.
Boom (Three-Section Boom)
4. Before installing the wire rope support on the inside surface of the top boom sectionís top plate, install the retracting wire rope and bend the plates (three places).
Install the wire rope support after installing the retracting wire rope.
6. Check that the support is not upside-down.
5. Install the wire rope support in accordance with the following steos.
(1) Apply thread locking compound (Threebond 1305 or equivalent) to the button bolts and use them to loosely fit the wire support.
(2) Tighten the bolts until the wire rope supportís longitudinal play is eliminated, then lock them in position with nuts.
Verify through the inspection holes that the wire rope support is pressed firmly against the stopper.
(3) Tighten the button bolts to a torque of 24.5 N-m (18.07 ft-lbf).
7. Install the sheave assembly at the rear end of the 2nd boom section after installing the telescoping cylinder in the 2nd boom section.
Install the sheave assembly with the clinched part on the inside.
Install the hexagon soket head bolt after installing the sheave assembly with the pin.
Apply thread locking compound (Loctite 262T or equivalent) to the hexagon socket head bolt. Tightening torque: 13.7 N-m (10.1 ft-lbf).
Boom (Three-Section Boom)
8. Before performing assembly, apply a line of grease of about 40 mm (1.57 inch) in width to the bottom part of the top boom sectionís inside surface in the longitudinal direction (see area marked by ì*î in Fig.)
3. Adjustment of Clearance between Boom Sections
1) Adjust dimension "a" (see Fig. 6) to the following values:
・With boom fully retracted: a =2mm (0.079in.) And it locks with the nut.
・ Over entire boom telescoping stroke : "a" = max 3mm (0.12in.)
2) Adjust dimension "b" (see Fig. 6) using shims ･ 1, ･2, ･3, such that the boom's degree of lateral bending and the boom's degree of lateral play comply with the following values:
・ Boom lateral bending: max. 20mm.(0.787in.)
・ Boom lateral play: max. 50mm (1.969in.).
[NOTE]
Boom Adjustment Procedures
Before performing this work, supply grease (TNR) to each slide plate and to each grease cup.
2. Top Slide Plate Installation Procedure
Apply thread locking compound (Threebond 1305 or equivalent) to the button bolts before using them to secure the slide plate. After tightening the button bolts, loosen each of them by half a turn and make sure the slide plate can move longitudinally (see Fig. 5).
Install the slide plates before assembling the boom.
Shim 1 serves to retain the other shims, so it must be installed last.
Boom (Three-Section Boom)
4. Telescoping wire rope adjusting procedure
1) With the top boom sectionís stopper touching the end of the 2nd boom section, use the specified jig to lock the top boom section and 2nd boom section in position. Make sure the telescoping cylinder is fully retracted.
2) Tighten the extending wire ropeís adjusting nut. Tightening torque : 4.9N-m (3.61ft-lbf)
3) Fit the extending wire rope lock nutís locking support.
4) Tightening torque : 37.8 N-m (27.88ft-lbf)
5) Bend the plate of each of the locking supports to prevent the lock nuts from working loose.
6) Remove the jig that was fitted in step 1) to hold the boom sections in their fully retracted positions. The wire ropeís tension will create a clearance between the end of the 2nd boom section and the stopper of the top boom section.
Boom (Three-Section Boom)
7) Fit the assembly formed through step 6) into the base boom section.
8) Tighten the adjusting nut of the boom retracting wire rope until the stopper of the top boom section touches the end of the 2nd boom section.
4) Position the boom horizontally, then extend the 2nd boom section and top boom section by 500 mm (19.68 inch) each.
With the hydraulic motor idling (with a flow rate of approximately 15 L/min.), fully retract the boom and lock the base boom section and 2nd boom section in position. (It is not necessary to lock them in position if pressure remains on the retraction side of the telescoping cylinder.)
Measure dimension ìBî shown in Fig.
Dimension ìBî : approx. 13mm (0.51 inch) (for reference)
9) Tighten the lock nut of the retracting wire rope. Tightening torque : 37.8 N-m (27.88ft-lbf)
5. Telescoping wire rope readjusting procedure
1) Unbend the bent parts of the locking supports on the extending wire ropeís lock nuts.
5) Tighten the retracting wire ropeís adjusting nut until the stopper of the top boom section touches the end of the 2nd boom section. Refer to Fig. in step 4-8).
6) Tighten the extending wire ropeís adjusting nut until the stopper of the top boom section is 4 ñ 5 mm (0.16 ñ 0.20 inch) away from the end of the 2nd boom section.
Refer to Fig. in step 4-1).
2) Remove the extending wire ropeís lock nuts and locking supports.
3) Loosen the retracting wire ropeís lock nut.
7) Once again tighten the retracting wire ropeís adjusting nut until the stopper of the top boom section touches the end of the 2nd boom section.
8) Position the boom horizontally, then extend the 2nd boom section and top boom section by 500 mm (19.68 inch) each.
With the hydraulic motor idling (with a flow rate of approximately 15L/min.), fully retract the boom.
Boom (Three-Section Boom)
Check whether the following boom conditions are satisfied.
- The stopper of the top boom section is touching the end of the 2nd boom section. (The top boom section is fully retracted.)
- Dimension ìBî is the same as when measured in step 4).
9) If the boom conditions stated in step 8) are not satisfied, make adjustments again in accordance with the following steps.
Refer to Fig. in step 4-1) and step 4-8).
- If the stopper of the top boom section is touching the end of the 2nd boom section but dimension ìBî is not the same as when measured in step 4), perform these steps :
(1) Slightly loosen the retracting wire ropeís adjusting nut.
(2) Slightly tighten the extending wire ropeís adjusting nut until dimension ìBî is the same as when measured in step 4).
- If dimension ìBî is the same as when measured in step 4) but the stopper of the top boom section is not touching the end of the 2nd boom section, perform these steps :
(1) Slightly tighten the retracting wire ropeís adjusting nut.
(2) Slightly loosen the extending wire ropeís adjusting nut until the stopper of the top boom section touches the end of the 2nd boom section.
10) Fit the locking supports over the extending wire ropeís lock nuts. If the supports are damaged, replace them with new ones.
11) Tighten the extending wire ropeís lock nuts
Refer to Fig. in step 4-1).
Be careful not to deform the locking supports. Tightening torque : 37.8N-m (27.88 ft-lbf)
12) Bend the plate of each of the supports to prevent the nuts from working loose.
Refer to Fig. in step 4-1).
13) Tighten the retracting wire ropeís lock nuts. Tightening torque : 37.8N-m (27.88 ft-lbf)
There is a case that the appearance and so on differ from the parts for this machine. Although there is not so much difference in functions and disassembly procedures, make sure of the serial number of this machine and the part sales unit described in the parts catalog before starting disassembling operations.
1. Base boom section
2. 2nd boom section
3. 3rd boom section 4. Top boom section 5. Grease nipple 6. Cap 7. Cover 8. Flange bolt 9. Pin 10. Retaining ring 11. Plain bearing 12. Slide plate 13. Button bolt 14. Flange bolt
15. Cover 16. Plate 17. Pin 18. Bolt 19. Grease nipple 20. Pin 21. Retaining ring 22. Bolt 23. Nut 24. Roller assembly 25. Pin
Nut 27. Set screw
28. Slide plate
2. Notes for Reassembly
1. Apply grease to the boom inside surfaces that rub against slide plates.
2. Press-fit the plain bearings at the base of the boom with their grease grooves on the outside (see Fig. 2).
29. Shim
30. Shim
31. Shim
32. Slide plate
33. Sheave
34. Pin
35. Retaining ring
36. Pin
37. Roller assembly
38. Hexagon socket head bolt
39. Spring washer
40. Slide plate
41. Bolt
42. Slide plate
43. Spring washer
44. Button bolt
45. Slide plate
46. Roller assembly
47. Pin
48. Cover
49. Nameplate
3. Bend down the plate on the boom elevating cylinder pivot pin after installing the bolts.
4. After installing the telescoping cylinder, turn back the bolt at the bottom of the telescoping cylinder until all play in the telescoping cylinder pivot pin on the 2nd boom section side is eliminated. Then, lock the bolt in position with the nut.
5. Install the wire rope support in accordance with the following steps (see Fig.):
Apply thread locking compound (Threebond 1305 or equivalent) to the button bolts and use them to loosely fit the wire rope support.
Tighten the bolts until the wire rope support's longitudinal play is eliminated, then lock them in position with the nuts. Verify through the inspection holes that the wire rope support is pressed firmly against the stopper.
Tighten the button bolts to a torque of 24.5 N-m (18.1 ft-lbf).
3. Boom Adjustment Procedures
Before performing this work, supply grease (TNR) to each slide plate and to each grease cup.
3.1 Top Slide Plate Installation Procedure
Apply thread locking compound (Threebond 1305 or equivalent) to the button bolts before using them to secure the slide plate. After tightening the button bolts, loosen each of them by half a turn and make sure the slide plate can move longitudinally (see Fig. 5).
3.2 Adjustment of Clearance between Boom Sections
1. Adjust dimension "a" (see Fig. 6 on next page) to the following values:
With boom fully retracted: a = 2 mm (0.08 in.)
Over entire boom telescoping stroke : a=max 3 mm (0.118in.)
2. Adjust dimension "b" (see Fig. 6 on next page) using shims-1, -2, and 3 such that the boom's degree of lateral bending and the boom's degree of lateral play comply with the following values:
Boom lateral bending: max. 35mm (1.38 in.)
(see Fig. 8 on next page)
Boom lateral play: max.80mm (3.15in.)
(see Fig. 9 on next page)
[NOTE]
Install the slide plates before assembling the boom. Shim-1 serves to retain the other shims, so it must be installed last.
Max 35mm (1 38 in )
Boom ( Four-Section Boom )
Boom fully retracted
Boom fullyextended
Adjustment of boom lateral bending
IW536-043002E
Max. 80mm (3.15 in.)
10kgf (22.1 lbf) 10kgf (22.1 lbf)
Boom fully extended
Adjustment of boom lateral play
IW536-0990E03
312-026-30100
There is a case that the appearance and so on differ from the parts for this machine. Although there is not so much difference in functions and disassembly procedures, make sure of the serial number of this machine and the part sales unit described in the parts catalog before starting disassembling operations.
1. Base boom section
2. 2nd boom section boom
Spacer
Cover
Plate
Pin
Bolt
2. Notes for Reassembly
1. Apply grease to the boom inside surfaces that rub against slide plates.
2. Press-fit the plain bearings at the base of the boom with their grease grooves on the outside.
31. Shim
32. Shim
33. Shim 34. Slide plate 35. Sheave 36. Pin 37. Grease nipple 38. Pin 39. Roller assembly 40. Hexagon socket head bolt 41. Spring washer 42. Pin 43. Retaining ring 44. Spring washer 45. Slide plate
46. Bolt
47. Button bolt
48. Slide plate
49. Slide plate
50. Roller assembly
51. Pin
52. Plate
53. Slide plate
54. Nameplate
3. Bend down the plate on the boom elevating cylinder pivot pin after installing the bolts.
4. After installing the telescoping cylinder, turn back the bolt at the bottom of the telescoping cylinder until all play in the telescoping cylinder pivot pin on the 2nd boom section side is eliminated. Then, lock the bolt in position with the nut.
Boom ( Five-Section Boom )
5. After installing the telescoping cylinder, turn back the bolt at the bottom of the telescoping cylinder until all play in the telescoping cylinder pivot pin on the 2nd boom section side is eliminated. Then, lock the bolt in position with the nut. (see Fig. on back page)
6. Install the wire rope support in accordance with the following steps (see Fig.4):
Apply thread locking compound (Threebond 1305 or equivalent) to the button bolts and use them to loosely fit the wire rope support.
Tighten the bolts until the wire rope support's longitudinal play is eliminated, then lock them in position with the nuts.
Verify through the inspection holes that the wire rope support is pressed firmly against the stopper.
Tighten the button bolts to a torque of 24.5 N-m (18.1 ft-lb).
3. Boom Adjustment Procedures
Before performing this work, supply grease (TNR) to each slide plate and to each grease cup.
3.1 Top Slide Plate Installation Procedure
Apply thread locking compound (Threebond 1305 or equivalent) to the button bolts before using them to secure the slide plate. After tightening the button bolts, loosen each of them by half a turn and make sure the slide plate can move longitudinally (see Fig. 5).
3.2 Adjustment of Clearance between Boom Sections
1. Adjust dimension "a" (see Fig. 6 on next page) to the following values:
With boom fully retracted: a = 2 mm (0.08 in.)
Over entire boom telescoping stroke : a=max 3 mm (0.118in.)
2. Adjust dimension "b" (see Fig. 6 on next page) using shims-1, -2, and 3 such that the boom's degree of lateral bending and the boom's degree of lateral play comply with the following values:
Boom lateral bending: max. 35mm (1.38 in.)
(see Fig. 8 on next page)
Boom lateral play: max.80mm (3.15in.)
(see Fig. 9 on next page)
[NOTE]
Install the slide plates before assembling the boom. Shim-1 serves to retain the other shims, so it must be installed last.
Max 35mm (1 38 in )
Boom ( Five-Section Boom )
Boom fully retracted
Boom fullyextended
Adjustment of boom lateral bending
IW536-043002E
Max. 80mm (3.15 in.)
10kgf (22.1 lbf) 10kgf (22.1 lbf)
Boom fully extended
Adjustment of boom lateral play
IW536-0990E03
312-029-40100
G-4 G-4
Telescoping cylinder (Three sections boom)
G-4 Telescoping cylinder (Three sections boom)
[NOTICE]
There is a case that the appearance and so on differ from the parts for this machine. Although there is not so much difference in functions and disassembly procedures, make sure of the serial number of this machine and the part sales unit described in the parts catalog before starting disassembling operations.
1. Structure
General View
Thread size and tightening torque
Telescoping cylinder (Three sections boom)
2. Notes for Reassembly of Cylinder Assembly
1. Make sure each seal, O-ring, and plain bearing is correctly aligned.
2. Before fitting the nut, apply adhesive (Loctite 638) to the thread on the rod as shown below.
・ Application area: From third crest to sixth crest (counting from end of piston) (see area marked with ※ in Fig. 3)
・ Nut tightening torque: 98 N-m (72.3 ft-lbf)
Telesco p in g c y linder ( Three sections boom )
3. Before fitting the rod cover, apply rust inhibitor (Threebond 1104 or equivalent) to the thread. Perform this step with each rod cover. (see Fig. 5)
・Tightening torque: 392 - 441 N･m (289- 325 ft-lbf)
4. After installing the cylinder, bend the end of the cylinder down onto the rod cover in one place. Perform this step with each cylinder.
3. Notes for Reassembly of Telescoping Cylinder
1. Install the sheave assembly with the clinched part on the inside.
Pass the extending wire rope through the part that is labeled ìNî in Fig.. Then, apply thread locking compound (Threebond 1305 or equivalent) to the bolts and use the bolts to retain the plate.
Tightening torque : 14 N-m (10.3 ft-lbf)
5. When passing the extending wire rope through the extending wire rope end loop support, be sure to follow these instructions:
Align the extending wire rope's center mark with the center of the extending wire rope end loop support.
After passing the extending wire rope through the extending wire rope end loop support, bend down the wire rope guides.
G-5
Telescoping Cylinder (Four-Section Boom)
G-5
G-5
Telescoping Cylinder (Four-Section Boom)
1. Structure
Telescoping Cylinder (Four-Section Boom)
Telescoping Cylinder (Four-Section Boom)
[NOTE]
There is a case that the appearance and so on differ from the parts for this machine. Although there is not so much difference in functions and disassembly procedures, make sure of the serial number of this machine and the part sales unit described in the parts catalog before starting disassembling operations.
7. Hexagon socket head bolt
13. Hexagon socket head bolt
19. Retaining ring
2.
3. Support
4. Nut
5.
6. Sheave assembly
8. Spring washer
9. Support
10. Spring washer
11. Bolt
12. Counterbalance valve assembly (※ )
14. Spring washer
15. Support
16. Bolt
17. Support
18. Sheave assembly
※ For details, refer to "Counterbalance Valve" section in chapter G.
Cylinder Assembly
1.
2. Spring washer
3. Support
4. O-ring
5. Hexagon socket head bolt
6. Roller assembly
7. Retaining ring
8. Plunger
9. O-ring
10. Backup ring
11. Retaining ring
12. Seal
13. O-ring
14. Plain bearing
15. Piston
16. Cylinder
17. Rod
18. Rod cover
19. O-ring
20. Packing
21. Backup ring
22. Dust seal
23. Check valve assembly
24. ----------------------
25. Roller assembly
26. Check valve assembly
27. Stopper
28. Plain bearing
29. Piston
30. Plain bearing
31. Packing
32. Backup ring
33. O-ring
20. Pin
21. Plate
22. Bolt
23. Support
34. Pipe
35. Rod
36. Cylinder
37. O-ring
38. Plain bearing
39. Rod cover
40. Machine screw
41. Slide plate
42. Machine screw
43. Slide plate
Telescoping Cylinder (Four-Section Boom)
2. Description of Operation
2.1 Control of Telescoping Sequence
1. When the No. 1 cylinder has been fully extended, the No.2 cylinder is extended.
2. When the No.2 cylinder has been fully retracted, the No.1 cylinder is retracted.
Telescoping Cylinder (Four-Section Boom)
2.2 Shock-Absorbing Mechanism of No. 2 Cylinder
1. Just before the No. 2 cylinder reaches the end of its retracting stroke, the return flow rate is progressively reduced by four chokes that each have a diameter of 0.04inch. The chokes serve to reduce the retracting speed and to minimize shock at the end of the stroke.
Oil flows at maximum rate.
Oil flows through four chokes.……
Oil flows through three chokes.
Oil flows through two chokes.……
Oil flows at minimum rate (through one choke).
Telescoping Cylinder (Four-Section Boom)
3. Notes for Reassembly of Cylinder Assembly
1. Make sure each seal, O-ring, and plain bearing is correctly aligned.
2. Before installing the pistons of the No.1 and No.2 cylinders, apply adhesive (Loctite 638) to the three consecutive crests of each rod's external thread, starting with the second crest (see the areas marked with "※ " in Fig.3).
Tightening torque: 98 N-m (10 kgf-m)
3. Apply thread locking compound to the items listed below before tightening those items.
For any tightening torque not shown in the drawings, refer to the "Mechanical Elements" chapter in the separate repair manual, "General Cautions".
Check valve mounting bolts (N) (four)
Hexagon socket head bolts (three) and nut (one)
Slide plate mounting bolts (M4) (two)
4. Before fitting the rod cover, apply rust inhibitor (Threebond 1104 or equivalent) to the thread. Perform this step with each rod cover.
Tightening torque: 253-289.1 ft-lb (343-392 N-m)
5. After installing the cylinder, bend the end of the cylinder down onto the rod cover in one place. Perform this step with each cylinder.
Telescoping Cylinder (Four-Section Boom)
6. When reassembling each roller assembly, apply grease to the pin.
4. Notes for Reassembly of Telescoping Cylinder
1. Install the sheave assembly at the rear end of the No.2 cylinder with the clinched part on the inside.
7. Tighten each of the hexagon socket head bolts on the top of the cylinder assembly to a torque of 17.3 ft-lb (23.5 N-m)
2. Install the sheave assembly at the front end of the No.2 cylinder with the clinched part on the outside.
3. Before installing the extending wire rope, install the retracting wire rope end loop support and the plate.
Telescoping Cylinder (Four-Section Boom)
4. When passing the extending wire rope through the extending wire rope end loop support, be sure to follow these instructions:
Align the extending wire rope's center mark with the center of the extending wire rope end loop support.
After passing the extending wire rope through the extending wire rope end loop support, bend down the two wire rope guides.
6. Tighten each of the support mounting bolts shown in Fig.13 to a torque of 14.5 ft-lb (19.6 N-m)
5. When passing the retracting wire rope through the retracting wire rope end loop support, be sure to follow these instructions:
Align the retracting wire rope's center mark with the center of the retracting wire rope end loop support.
After passing the retracting wire rope through the retracting wire rope end loop support, apply thread locking compound to the machine screws and use the machine screws to install the wire rope guides.
7. When installing the telescoping cylinders in the boom, align as shown in Fig.14 the groove (marked with a "A") in the outside of the sheave at the rear end of the No.2 cylinder.
8. Apply grease to the surface that rubs against the slide plate (the bottom surface of the No.2 cylinder) (see Fig.4). At the same time, apply grease to the top surface of the No.2 cylinder.
Telescoping Cylinder (Four-Section Boom)
5. Cautions about Telescoping Wire Rope Adjustment
1. To prevent the nut of the extending wire rope from hitting the sheave ass'y-6 and the nut of the retracting wire rope from hitting the sheave ass'y-18, adjust the wire rope so that the projecting length of the extending wire rope is 4.25 in. or shorter and the one of thhe retracting wire rope is 2.83 in. or shorter (See the Fig.15)
2. Attach the extending wire rope-2 and retracting wire rope-5, and fold the four wire rope guides. Then attach the two wire guide supports-26 after applying screw locking agent to the threaded portion of the machine screw-27.
6. Telescoping Wire Rope Adjustment Procedure
6.1 Wire rope adjustment with the telescoping cylinder out of the boom
1. Fully retract the telescoping cylinder. At this time, maintain pressure on the retraction side of the telescoping cylinder to prevent dimension "D" (see Fig. 16) from changing.
Dimension D: 6 in.
3. With the heads of the extending wire rope adjusting bolts pressing firmly against the adjusting bolt mounting surface, adjust dimension "E" (see Fig.18) to 4.72-4.76 inch.
At this time, make sure the most external flats of the adjusting bolts are horizontal as shown in Fig.18.
4. With the heads of the retracting wire rope adjusting bolts pressing firmly against the adjusting bolt mounting surface, tighten the adjusting bolts until the plate is slightly separated from the cylinder support.
At this time, make sure the most external flats of the adjusting bolts are horizontal as shown in Fig.19.
Telescoping Cylinder (Four-Section Boom)
8. After secure the nuts-4 and 28 using the lock nuts.
9. After adjustment is completed, thrust the adjusting bolt locking support against the horizontal face of the extending wire rope adjusting bolt and secure the support using the hexagon head bolts-13 and the spring washers-14. (see the Fig.21)
5. Use the specified jig to retain the top boom stretch support in the position at which dimension "C" (see Fig.20) is 11.57 inch.
10. After adjustment is completed, thrust the adjusting bolt locking support against the horizontal face of the retracting wire rope adjusting bolt and secure the support using the hexagon head bolts-13 and the spring washers-14. (see the Fig.22)
6. With the jig still fitted, tighten the extending wire rope adjusting nut and lock it in position using the lock nut. (see Fig.20).
Adjusting nut tightening torque：
3.6 ft-lb (4.9 N-m) (If the length of the wire rope projecting from the adjusting nut is too short to tighten the nut using the jig, tighten the extending wire rope adjusting bolts on the right and left close to the boom head equally.)
Adjusting bolt tightening torque：
7.2 ft-lb (9.8 N-m)
7. With the jig fitted, tighten the retracting wire rope adjusting nut until the jig slightly comes off. (If the length of the wire rope projecting from the adjusting nut is too short to tighten the nut using the jig, tighten the retracting wire rope adjusting bolt close to the boom head.)
Telescoping Cylinder (Four-Section Boom)
6.2 Wire rope adjustment with the telescoping cylinder installed in the boom
3. When F is longer than 4mm Perform the "6.1 Wire rope adjustment with the telescoping cylinder out of the boom" again.
1. Telescope the boom for several strokes and check the dimension of F (clearance between the top boom section and 3rd boom section). If F is 0.08in. or shorter re-adjustment is not necessary.
2. When F is longer than 0.08in. and does not exceed 0.16in.
Remove the top cover. (Take care not to damage the cord on the cord reel.)
Remove the adjusting bolt locking support-15, hexagon head bolt-13 and the spring washer-14, and loosen the extending wire rope adjusting bolts-16 on the right and left fot one turn.(see the Fig.21)
Remove the adjusting bolt locking support-15, hexagon head bolt-13 and the spring washer-14, and tighten the retracting wire rope adjusting bolts until F is 0.08in. or shorter.
(see the Fig.22)
Attach the adjusting bolt locking support-15, hexagon head bolt 13-and spring washers-14 (both for the retracting wire rope and for the extending wire rope).Then attach the top cover.
G-6
Telescoping Cylinder (Five-Section Boom)
G-6
G-6
Telescoping Cylinder (Five-Section Boom)
1. Structure General View
Telescoping Cylinder (Five-Section Boom)
Telescoping Cylinder (Five-Section Boom)
There is a case that the appearance and so on differ from the parts for this machine. Although there is not so much difference in functions and disassembly procedures, make sure of the serial number of this machine and the part sales unit described in the parts catalog before starting disassembling operations. 1.
※ For details, refer to "Counterbalance Valve" section in chapter G.
46.
48.
Telescoping Cylinder (Five-Section Boom)
1. O-ring 8. Body
2. Spring 9. O-ring
3. Check valve 10. O-ring
4. Rod 11. Hexagon socket head bolt
5. O-ring 12. Plug
6. Backup ring 13. Spacer
7. Cap
Check Valve Assembly (Cylinder Assembly Part24) Detail
2. Description of Operation
2.1 Control of Telescoping Sequence
1. When the No.1 cylinder has been fully extended, the No.2 cylinder is extended.
Telescoping Cylinder (Five-Section Boom)
Telescoping Cylinder (Five-Section Boom)
Telescoping Cylinder (Five-Section Boom)
2.2 Shock-Absorbing Mechanism of No. 3 Cylinder
1. Just before the No. 3 cylinder reaches the end of its retracting stroke, the return flow rate is progressively reduced by four chokes that each have a diameter of 1 mm. The chokes serve to reduce the retracting speed and to minimize shock at the end of the stroke.
Oil flows at maximum rate.
Oil flows through four chokes.
Oil flows through three chokes.
Oil flows through two chokes.
Oil flows at minimum rate …… (through one choke).
Telescoping Cylinder (Five-Section Boom)
3. Notes for Reassembly of Cylinder Assembly
1. Make sure each seal, O-ring, and plain bearing is correctly aligned.
2. Before installing the pistons of the No.2 and No.3 cylinders, apply adhesive (Loctite 638) to the three consecutive crests of each rod's external thread, starting with the second crest (see the areas marked with "※ " in Fig. 3).
Tightening torque: 72.4 ft-lb (98.1 N-m)
3. Before installing the piston of the No.1 cylinder, apply adhesive (Loctite 638) to the four consecutive crests of the rod's external thread, starting with the third crest (see the area marked with "※※ " in Fig.3).
Tightening torque: 72.4 ft-lb (98.1 N-m)
4. Apply thread locking compound (Threebond 1305) to the items listed below before installing the items (see Figs. 4 - 7).
For any tightening torque not shown in the drawings, refer to the "Mechanical Elements" chapter in the separate repair manual, "General Cautions".
Check valve mounting bolts (N) (eight)
Machine screws (M4x2) and button bolts (M6x2) used to mount slide plates at front ends of No.1 and No.2 cylinders
Telescoping Cylinder (Five-Section Boom)
Machine screws (M4x2) used to mount slide plate at rear end of No.2 cylinder
Hexagon socket head bolts (M8x4) on top of No.3 cylinder's front end
Hexagon socket head bolts (M12x8) at rear end of cylinder assembly
5. Before fitting the rod cover, apply rust inhibitor (Threebond 1104 or equivalent) to the thread. Perform this step with each rod cover.
Tightening torque: 253-289.1 ft-lb (343-392 N-m)
6. After installing the cylinder, bend the end of the cylinder down onto the rod cover in one place. Perform this step with each cylinder.
Telescoping Cylinder (Five-Section Boom)
7. When reassembling each roller assembly, apply grease to the pin.
4. Notes for Reassembly of Telescoping Cylinder
1. Install the sheave assembly at the rear end of the No. 3 cylinder with the clinched part on the inside.
2. Install the sheave assembly at the front end of the No.3 cylinder with the clinched part on the outside.
3. Before installing the extending wire rope, install the retracting wire rope end loop support and the plate.
Telescoping Cylinder (Five-Section Boom)
4. When passing the extending and retracting wire ropes through their respective wire rope end loop support, be sure to follow these instructions:
Align the wire rope's center mark with the center of the wire rope end loop support.
After passing each wire rope through the wire rope end loop support, bend down the wire rope guides.
Extending wire rope: two wire rope guides
After passing the retracting wire rope through the retracting wire rope end loop support, apply thread locking compound to the machine screws and use the machine screws to install the wire rope guides.
Retracting wire rope: six wire rope guides.
6. When installing the telescoping cylinders in the boom, align as shown in Fig.15 the groove (marked with a "A") in the outside of the sheave at the rear end of the No.3 cylinder.
5. Tighten each of the support mounting bolts shown in Fig.14 to a torque of 14.5 ft-lb (19.6 N-m).
7. Apply grease to the surface that rubs against the slide plate (see Fig.4,Fig.5). At the same time, apply grease to the top surface of the No.3 cylinder.
Telescoping Cylinder (Five-Section Boom)
5. Telescoping Wire Rope Adjustment Procedure
5.1 Wire rope adjustment with the telescoping cylinder out of the boom
1. Fully retract the telescoping cylinder. At this time, maintain pressure on the retraction side of the telescoping cylinder to prevent dimension "D" (see Fig.16) from changing.
Dimension D: 5.75 in.
2. Attach the extending wire rope-2 and retracting wire rope-5, and fold the two wire rope guides. Then attach the two wire guide supports-25 after applying screw locking agent to the threaded portion of the machine screw-26.
4 With the head of the retracting wire rope adjusting bolt pressing firmly against the adjusting bolt mounting surface, tighten the adjusting bolt until the plate is slightly separated from the cylinder support (see Fig.19).
At this time, make sure the most external flat of the adjusting bolt is horizontal as shown in Fig.19.
3. With the heads of the extending wire rope adjusting bolts pressing firmly against the adjusting bolt mounting surface, adjust dimension "E" (see Fig.18) to 4.39 - 4.43 inch.
At this time, make sure the most external flats of the adjusting bolts are horizontal as shown in Fig.18.
5. Use the specified jig to retain the top boom stretch in the position at which dimension "C" (see Fig.20) is 13.31 inch.
Telescoping Cylinder (Five-Section Boom)
6. With the jig still fitted, tighten the extending wire rope adjusting nut and lock it in position using the lock nut (see Fig.20).
Adjusting nut tightening torque: 3.6 ft-lb (4.9 N-m) (If the length of the wire rope projecting from the adjusting nut is too short to tighten the nut using the jig, tighten the extending wire rope adjusting bolts on the right and left close to the boom head equally.)
Adjusting bolt tightening torque: 7.2 ft-lb (9.8 N-m)
7. With the jig fitted, tighten the retracting wire rope adjusting nut until the jig slightly comes off. (If the length of the wire rope projecting from the adjusting nut is too short to tighten the nut using the jig, tighten the retracting wire rope adjusting bolt close to the boom head.
8. After 7., secure the nuts-4 using the lock nuts.
9. After adjustment is completed, thrust the adjusting bolt locking support against the horizontal face of the extending wire rope adjusting bolt and secure the support using the hexagon head bolts-13 and the spring washers-14. (see the Fig.21)
10.After adjustment is completed, thrust the adjusting bolt locking support againt the horizontal face of the retracting wire rope adjusting bolt and secure the support using the hexagon head bolts-13 and the spring washers-14. (see Fig.22)
1. Telescope the boom for several strokes and check the dimension of F (clearance between the top boom section and 3rd boom section). If F is 0.08in. or shorter re-adjustment is not necessary.
2. When F is longer than 0.08 in. and does not exceed 0.16 in.
Remove the top cover. (Take care not to damage the cord on the cord reel.)
Telescoping Cylinder (Five-Section Boom)
Remove the adjusting bolt locking support-15, hexagon head bolt-13, and the spring washer-14, and loosen the extending wire rope adjusting bolts-16 on the right and left for one turn. (see the Fig.21)
Remove the adjusting bolt locking support-15, hexagon head bolt-13 and the spring washer-14, and tighten the retracting wire rope adjusting bolts until F is 0.08 in. or shorter. (see the Fig.22)
Attach the adjusting bolt locking support-15, hexagon head bolt-13 and spring washers-14 (both for the retracting wire rope and for the extending wire rope). Then attach the top cover.
3. When F is longer than 0.16 in.
Perform the "5.1 Wire rope adjustment with the telescoping cylinder out of the boom" again.
G-7 G-7
Counterbalance Valve (Telescoping)
G-7 Counterbalance Valve (Telescoping)
[NOTICE]
There is a case that the appearance and so on differ from the parts for this machine. Although there is not so much difference in functions and disassembly procedures, make sure of the serial number of this machine and the part sales unit described in the parts catalog before starting disassembling operations.
1. Structure
General View
Counterbalance Valve (Telescoping)
Thread size and tightening torque
