Nexen AIR CHAMP VC500 User manual

1FORM NO. L-21156-E-1207
Single Post Caliper Brake
VC500
®
DIST. AUTORIZADO
MEX (55) 53 63 23 31 QRO (442) 1 95 72 60
MTY (81) 83 54 10 18 [email protected]

2
FORM NO. L-21156-E-1207
In accordance with Nexen’s established policy of constant product improvement, the specifications contained in this
manual are subject to change without notice. Technical data listed in this manual are based on the latest information
available at the time of printing and are also subject to change without notice.
Technical Support: 800-843-7445
[phone]
www.nexengroup.com
Copyright 2007 Nexen Group, Inc.
Nexen Group, Inc.
560 Oak Grove Parkway
Vadnais Heights, Minnesota 55127
ISO 9001 Certified
Read this manual carefully before installation and operation.
Follow Nexen's instructions and integrate this unit into your system with care.
This unit should be installed, operated and maintained by qualified personnel ONLY.
Improper installation can damage your system or cause injury or death.
Comply with all applicable codes.
DANGER
®
DIST. AUTORIZADO
MEX (55) 53 63 23 31 QRO (442) 1 95 72 60
MTY (81) 83 54 10 18 [email protected]

3FORM NO. L-21156-E-1207
Table of Contents
Installation -----------------------------------------------------------------------------------------------------------------------------------------4
Friction Facing Adjustment -----------------------------------------------------------------------------------------------------------------6
Air Connections -------------------------------------------------------------------------------------------------------------------------------7
Lubrication ----------------------------------------------------------------------------------------------------------------------------------------7
Operational Modes -----------------------------------------------------------------------------------------------------------------------------8
Maintenance --------------------------------------------------------------------------------------------------------------------------------------9
Parts Replacement --------------------------------------------------------------------------------------------------------------------------10
Replacement Parts ---------------------------------------------------------------------------------------------------------------------------12
Parts List ----------------------------------------------------------------------------------------------------------------------------------------12
Warranty -----------------------------------------------------------------------------------------------------------------------------------------13
------------------------------------------------------------------------------------------------------------------------------------------------------
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MEX (55) 53 63 23 31 QRO (442) 1 95 72 60
MTY (81) 83 54 10 18 [email protected]

4
FORM NO. L-21156-E-1207
ACTUATOR
NOTE: The Spring Actuator Assembly is designed for
extended service life. Due to this long product life, the
assembly is permanently sealed to protect users from
potentially dangerous spring forces. Do not attempt
to service the actuator or remove the welds on the
actuator bolts.
ALL SERVICE MUST BE PERFORMED BY TRAINED
NEXEN PERSONNEL.
Figure 2
Spring
Actuator
Assembly
INSTALLATION
Dial
Indicator
Figure 1
DIAMETER
mm [inches]
PRODUCT
NO.
QD
BUSHING
TORQUE
Nm [ft-lb]
356 [14] 934202 E 81 [60]
406 [16] 934203 E 81 [60]
457 [18] 934204 J 182.5 [135]
508 [20] 934205 J 182.5 [135]
559 [22] 934206 J 182.5 [135]
610 [24] 934207 J 182.5 [135]
Table 1 (Non-Ventilated Discs)
RETEMAID
]sehcni[mm
TCUDORP
.ON
DQ
GNIHSUB
EUQROT
]bl-tf[mN
]52.81[464 002439 J ]531[5.281
]12[335 003439 J ]531[5.281
]42[016 004439 J ]531[5.281
Table 2 (Ventilated Discs)
DISC
1. Thoroughly inspect the tapered bore of the disc hub
and tapered surface of the Q.D. bushing. Remove
any dirt, grease, or foreign material. Do not use
lubricants for this installation.
2. Insert the Q.D. bushing into the disc hub, aligning
the untapped holes in the bushing flange with the
tapped holes in the disc hub.
3. Insert the pull-up bolts and tighten to the
recommended torque (See Tables 1 and 2).
NOTE: Runout is minimized if a dial indicator is used
as the pull-up bolts are tightened. Place contact tip of
the Dial Indicator on the machined surface of the Rotor
to measure runout. Runout should be less than 0.254-
0.381 mm [0.010-0.015 inches] (See Figure 1).
CAUTION
Exceedingthespecifiedtightening torquecreates
excessive pressures in the hub. Leave a gap
between the flange of the Q.D. bushing and the
disc hub to ensure a proper fit of the Q.D. bushing
onto the shaft or breakage can occur.
4. To remove the Q.D. bushing, remove the pull-up
bolts and reinsert into the threaded holes. Tighten
the pull-up bolts to push the disc off the Q.D.
bushing.
®
DIST. AUTORIZADO
MEX (55) 53 63 23 31 QRO (442) 1 95 72 60
MTY (81) 83 54 10 18 [email protected]

5FORM NO. L-21156-E-1207
Figure 3
FRAME
NOTE: The VC500 Spring Actuator Assembly is factory
calibrated to a 12.7 mm [0.500 in] wide brake disc. No
adjustment is necessary when mating a disc of this
size.
If using a thicker or thinner disc, offset shoes will be
required. See the FRICTION FACING ADJUSTMENT
section to readjust for a wider or thinner disc.
1. Release the brake with at least 4.1-4.8 bar [60-70
psi] air pressure.
2. Position the brake shoes on the disc and release the
air pressure to lock the brake in place.
NOTE:Brakeshoesmustbemountedwithapproximately
1.6 mm [1/16 inch] space between the outside edge of
the shoe and the outer diameter of the disc.
2. Align the frame on a support (customer supplied)
so the brake arms are parallel with the brake disc
and the brake shoes are positioned at least 1.6 mm
[1/16 inches] in from the disc edge.
NOTE: The support must be capable of sustaining loads
produced during braking.
If using shims under the Frame (Item 1): Do not to warp
the Frame when tightening the Cap Screws (customer
supplied).
Vertical Mounting only
NOTE: A special Bracket and Screw kit (Items 43 & 42)
is supplied with each VC500 unit to be used in vertical
mounting applications.
If mounting vertically, attach the Bracket before
proceeding with step three:
Secure the Bracket to the bottom of the Actuator
Mount (Item 4) with the supplied Screws. Position the
Bracket with the notch straddling the arm of the frame
to provide support (See Figure 4). Hold the Bracket
tightly to the frame, and tighten the Screws to create
a hard stop.
3. Release the VC500 from the disc.
4. Tighten the Cap Screws (customer supplied) and
the Lock Washers (Item 20) to 67.8 Nm [50 ft-lb]
torque (See Figure 3).
CAUTION
The Cap Screws (Item 17) must sustain the loads
produced by themountingtorque. Thetorquerating
specified in Tables 1 & 2 allows a significant load
safety factor. DO NOT EXCEED TORQUE LIMITS
SPECIFIED FOR THE CAP SCREWS.
Cap Screws &
Lock Washers
(customer
supplied)
Frame
(Item 1)
Spring Actuator
Assembly
Figure 4
Frame
(Item 1)
Frame Arm Actuator Mount
(Item 4)
Cap Screw
(Item 42)
Bracket
(Item 43)
®
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MEX (55) 53 63 23 31 QRO (442) 1 95 72 60
MTY (81) 83 54 10 18 [email protected]

6
FORM NO. L-21156-E-1207
FRICTION FACING ADJUSTMENT
Figure 5
Do not allow air pressure to drop
during brake linkage adjustment.
High spring forces and possible
pinch points require constant air
pressure to prevent operator injury.
Always keep hands and fingers out
of the linkage assembly area when
adjusting and actuating the brake.
NOTE: The VC500 Spring Actuator Assembly is factory
calibrated to a 12.7 mm [0.500 in] wide brake disc. No
adjustment is necessary when mating to a disc of this
size. If using a thicker or thinner disc, offset shoes will
be required.
WARNING
WARNING
Do not wear facings down within 0.762 mm
[0.030 in] of the iron facing shoe. Loss of
clamping force and machine damage will
result. Monitor facing wear closely and
replace before worn to this dimension.
Adjustment of linkage is required for any
disc above or below 12.4 mm [0.500 in]
thick. Loss of torque or failure of the manual
release function may result.
Spacing as
described in
Step 8
Actuator Cap
(Item 10)
Friction Facings
(Item 6)
Cap Screws
(Item 34)
Clevis
(Item 14)
Linkage Assembly
Turnbuckle
(Item 23)
Jam Nut (RH)
(Item 19)
Rod End (RH)
(Item 16)
Rod End (LH)
(Item 17)
Rod End (LH)
(Item 17)
Item 3
Actuator
Face
Jam Nut (LH)
(Item 36)
Jam Nut (RH)
(Item 19)
Jam Nut (LH)
(Item 36)
Rod End (RH)
(Item 16)
See Linkage
Assembly Above
Screw (Item 28) and
Lock Nut (Item 18)
1. If the brake is mounted and clamping on the disc,
apply >4.1 bar (>60 psi) to release the spring
actuator force from the linkage. The brake must be
disengaged and unloaded for linkage adjustment
(See Warning note to the right).
NOTE: Brake shoes and detent pins must be installed
in order to perform the following procedure.
2. Remove the brake guard by removing cap screws
(Item 34) (See Figure 5).
3. Remove only the center rod ends (Item 17 & 16)
from the clevis (Item 14) by removing the locking
nuts (Item 18) and screws (Item 28).
4. Apply >4.1 bar (>60 psi) to the spring actuator.
5. With the air pressure applied rotate the clevis (Item
14) until the rear end is 100.9 mm (3.97 in) away
from the face of the actuator.
6. Insert the center rod ends (Items 16 & 17) back
into the clevis (Item 14) and tighten the locking nuts
(Item 18) to 45.2 Nm (435 in-lb).
Once the rod ends are installed, retighten the clevis
jam nut (Item 19), apply servicable thread locker to
jam nut and torque to 4.5 Nm (40 in-lb).
7. Clevis adjustment is now complete.
8. It is critical that the linkage assemblies are both
equal length. To ensure this, adjust both linkages
by rotating the turnbuckle until the spacing between
the arm (Item 3) and the actuator cap (Item 10) is
equal -- see drawing for clarification. This will create
a starting point for the final facing adjustment.
®
DIST. AUTORIZADO
MEX (55) 53 63 23 31 QRO (442) 1 95 72 60
MTY (81) 83 54 10 18 [email protected]

7FORM NO. L-21156-E-1207
AIR CONNECTIONS
Pneumatically actuated devices require clean, pressure
regulated, and lubricated air for maximum performance
and long life. Your Nexen distributor carries filters,
regulators, and lubricators specifically designed to
operate with Nexen clutches, brakes, and valves.
Piping diagrams are included in this manual for a variety
of braking functions. Refer to OPERATIONAL MODES
for details.
CAUTION
Do not use rigid pipe or tubing when connecting
directly to the Brake.
Prevent unshielded air hoses from rubbing on
metal surfaces or edges, as this will cause rapid
deterioration of the hose.
Actuator is spring loaded
under extreme pressure. Do
not disassemble Actuator.
If Actuator malfunctions,
replace the Actuator
or contact Nexen. The
turnbuckle assembly can be
used to physically release
the spring.
WARNING
FIGURE 6
LUBRICATION
All pivot points on the VC500 Caliper Brake use self-lubricated high PV bearings.
For tension control applications where the disc is held at elevated temperatures for extended periods, use a light
machine oil on Bearings (Items 11, 12, 13, 22, 28, and 37) (See Figure 6).
37
11
13
12
28
22
NOTE: The VC500 Caliper Brake has a .250–18 NPT
air inlet port. A .250–18 NPT (male) and .250 ISO
7/1 (female) adapter is provided for metric plumbing
applications.
NOTE: DO NOT assume the thread lengths are equal
on the rod ends. Use the actuator cap as a reference
to equalize linkage length (as described in step 11).
9. With >4.1 bar (>60 psi) still applied, rotate the
turnbuckles (Item 23) equally until contact is made
between the facings (Item 6) and the brake disc.
Then, back off 1/4 turn on each turnbuckle.
NOTE: The gap between the brake arm (Item 3) and
the actuator cap (Item 10) should be equal on both
sides. If not, continue to adjust turnbuckles until both
arms are equally spaced and the facings (Item 6) are
in contact with the brake disc.
10. Carefully re-tighten the jam nuts (Item 19 and 26) to
ensure that no turnbuckle movement is detected.
Apply serviceable thread lock and torque jam nuts
to 4.5 Nm (40 in-lb).
NOTE: LH jam nuts(Item 36) will have a paint mark to
identify them from the RH thread nuts.
11. Apply a serviceable thread lock to the cap screws
(Items 34) and reinstall the brake guard (Item 24).
®
DIST. AUTORIZADO
MEX (55) 53 63 23 31 QRO (442) 1 95 72 60
MTY (81) 83 54 10 18 [email protected]

8
FORM NO. L-21156-E-1207
OPERATIONAL MODES
Figure 7
NORMAL SPRING ENGAGED MODE
This mode is for occasional duty, non-cyclic applications only. A hold-off pressure of 4.1-4.8 bar [60-70 psi] is used
to compress the spring inside the Actuator canister. A control signal is used to release the hold-off pressure, thus
applying full spring-engaged torque to the brake (See Figure 7).
SPRING ENGAGED-DUAL AIR MODE
This mode allows the selection of any value of spring engaged torque (from zero to full scale) available with a particular
disc size by relieving a percentage of the minimum Hold-Off pressure 4.1 bar [60 psi]. The remaining pressure,
balanced against the spring force, reduces the output of the Actuator (See Figure 8).
EXAMPLE: A standard spring set brake with a 18 inch disc has a full rated spring engaged torque of 3,480 Nm
[30,800 in-lb] when using the minimum hold-off pressure of 4.1 bar [60 psi]. If it is desired to have 60% of this
torque or 2,016 Nm [18,000 in-lb], relieve the hold-off pressure 60 percent or 1.9 bar [36 psi], leaving 2.2 bar [24
psi] hold-off pressure.
Figure 8
NORMAL SERVICE MODE
Below is a standard air brake control circuit. On-off air control is achieved by the 3-way valve. Torque is accomplished
by the regulation of air pressure.
NOTE: Maximum operating pressure is 6.9 bar [100 psi] (See Figure 6).
3-Way Control N.C.
Filter
Lubricator
3-Way Manual
Control
Air Supply
Regulator
Power
Source
3-Way Manual
Control
Air Supply
Regulator
Power Source
3-Way Control N.C.
Power Source
Regulator 3-Way Control
N.C.
Lubricator
Filter
®
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MEX (55) 53 63 23 31 QRO (442) 1 95 72 60
MTY (81) 83 54 10 18 [email protected]

9FORM NO. L-21156-E-1207
MAINTENANCE
Tomanually release The brake:
1. Remove brake guard (Item 24).
2. Using a thin 3/4" wrench, loosen the four jam nuts
(Item 19) on the rod ends (Items 16 & 17).
3. Using a 1" wrench, rotate the turnbuckles (Item 23)
equally until a noticeable gap is visible between the
facings (Item 6) and the brake disc.
NOTE: Nexen recommends rotatingtheturnbuckles 1/2
turn at a time on each side until the brake is completely
disengaged.
Toreengage The brake:
Follow instruction in friction facing adjustment
section.
MANUAL RELEASE
TABLE 3
GENERAL
1. Adhere to the following bolt tightening torques (See
Table 3).
2. Inspect Actuator exterior.
3. Check tightness of air line connections, and
condition of all air lines. Replace worn or damaged
air lines.
4. Inspect Friction Facings for wear. Replace before
contact is made between shoes and brake disc.
5. Lubricate items requiring lubrication (See
LUBRICATION).
Actuator is spring loaded
under extreme pressure.
Do not disassemble
Actuator. If Actuator
malfunctions, replace the
Actuator or contact Nexen.
WARNING
Figure 9
Jam Nut
Rod End
(Item 16)
Rod End
(Item 17)
Rod End
(Item 17)
Turnbuckle
(Item 23)
Rod End
(Item 16)
Friction Facing
(Item 6)
Brake Arm
(Item 3)
Brake Arm
(Item 3)
Actuator
Cap (Item
10)
Jam Nut
(Item 36, LH)
(Item 19)
(Item 19) (Item 36, LH)
ITEM
No.
DESCRIPTION TORQUE
Nm [ft-lb]
15 Machine Screw
(friction facing)
12-16 [8-11]
19 Jam Nuts (linkage) 20-27 [15-20]
18 Lock Nuts (linkage) 44-57 [33-42]
33 Lock Nut (post) finger tighten,
then bend tab
36 Jam Nuts-LH (linkage) 20-27 [15-20]
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10
FORM NO. L-21156-E-1207
1. Apply >4.1 bar [m >60 psi] to open shoes
or manually release the brake (See MANUAL
RELEASE section for details).
2. Remove the shoe pins (Item 8).
3. Remove the friction facing shoe assembly (Items 5,
6, and 15).
NOTE: The Machine Screws are assembled with an
anaerobic locking compound. To loosen the compound,
insert a properly fitting screwdriver into the head of
the Machine Screw and strike the screwdriver with a
hammer. Never use an impact wrench to remove the
Machine Screws.
Figure 9
Shoe
Pins
(Item 8)
Friction
Facing
(Item 6)
Machine
Screw
(Item 15)
Shoe
Pins
(Item 8)
Friction Facing
Shoe Assembly
(Items 5, 6, and 15)
PARTS REPLACEMENT
FRICTION FACINGS
NOTE: When replacing Friction Facings, inspect the Friction Disc for scoring or grooves. If necessary, the Friction
Disc may be machined. A maximum of 0.76 mm [0.030 in] may be removed from each side of the Friction Disc
before it is necessary to replace the Friction Disc.
4. Remove the old Machine Screws (Item 15) and old
Friction Facings (Item 6).
5. Using new Machine Screws (Item 15), install new
Friction Facings (Item 6) (See Figure 12).
6. Tighten the new Machine Screws (Item 15) to 12-
16 Nm [8-11 ft-lb] torque.
7. Reinstall the Friction Facing Shoe Assembly (Items
5, 6, and 15) and Shoe Pins (Item 8).
8. Perform Friction Facing clearance adjustment (See
FRICTION FACING ADJUSTMENT section for
details).
WARNING
Do not wear facings within 0.762 mm [0.030 in] of the iron facing shoe. Loss of
clamping torque and machine damage will result. Monitor facing wear closely and
replace before worn to this dimension.
Adjustment of linkage is required for any disc above or below 12.4 mm [0.500 in]
thick. Loss of torque or failure of the manual release function may result.
®
DIST. AUTORIZADO
MEX (55) 53 63 23 31 QRO (442) 1 95 72 60
MTY (81) 83 54 10 18 [email protected]