Nexen AIR CHAMP FMBS-875 User manual

(i)
Flange Mounted Spring Engaged
Brake
Model FMBS-875
FORM NO. L-20206-A-0601
AIR CHAMP PRODUCTS
User Manual

(ii)
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
Nexen Group, Inc.
560 Oak Grove Parkway
Vadnais Heights, Minnesota 55127
ISO 9001 Certified
Copyright 2000 Nexen Group, Inc.
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.
WARNING

(iii)
TABLE OF CONTENTS
Introduction---------------------------------------------------------------------------------------------------------------------------------------- 1
Installation ---------------------------------------------------------------------------------------------------------------------------------------- 1
Air Connections-------------------------------------------------------------------------------------------------------------------------------- 1
Lubrication---------------------------------------------------------------------------------------------------------------------------------------- 2
Troubleshooting ---------------------------------------------------------------------------------------------------------------------------------3
Parts Replacement ----------------------------------------------------------------------------------------------------------------------------3
Replacement Parts ----------------------------------------------------------------------------------------------------------------------------7
Parts List -------------------------------------------------------------------------------------------------------------------------------------------7
Warranties-----------------------------------------------------------------------------------------------------------------------------------------8

1FORM NO. L-20206-A-0601
INTRODUCTION
Read this manual carefully, making full use of its explanations and instructions. The “Know How” of safe, continuous,
trouble-free operation depends on the degree of your understanding of the system and your willingness to keep all
components in proper operating condition. Pay particular attention to all NOTES, CAUTIONS, and WARNINGS to avoid
the risk of personal injury or property damage. It is important to understand that these NOTES, CAUTIONS, and
WARNINGS are not exhaustive. Nexen cannot possibly know or evaluate all conceivable methods in which service may
be performed, or the possible hazardous consequences of each method. Accordingly, anyone who uses a procedure
that is not recommended by Nexen must first satisfy themselves that neither their safety or the safety of the product will
be jeopardized by the service method selected.
INSTALLATION
FMBS-875 MOUNTED ON A NEMA C-FACED
MOTOR (See Fig. 1)
1. Insert customer supplied key into motor shaft keyway.
2. Slide FMBS-875 onto motor shaft and secure with
customer supplied socket head cap screws.
3. Tighten customer supplied socket head cap screws
to 12 ft. lbs. [16 N•m] torque.
4. Install Housing Guard.
FMBS-875 MOUNTED BETWEEN GEAR REDUCER
AND NEMA C-FACED MOTOR (See Fig. 1)
1 Insert Nexen supplied Key (Item 26) into FMBS-875
output shaft.
2. Slide FMBS-875 output shaft into gear reducer.
3. Secure FMBS-875 to gear reducer, using customer
supplied socket head capscrews and lockwashers
4. Tighten customer supplied socket head cap screws
and lockwashers to 12 ft. lbs. [16 N•m] torque.
5. Mount NEMA C-Faced motor (See FMBS-875
MOUNTED ON A NEMA C-FACED MOTOR).
6. Install Housing Guard.
FIGURE 1
Input or
Motor End
Output or
Gearbox End
Nexen Supplied
Key
AIR CONNECTIONS
Although Nexen’s FMBS-875 is spring engaged and air
disengaged with a maximum operating air pressure of 80
PSI, use only enough air pressure to insure proper disen-
gagement for the application. Operating air pressures over
80 PSI will eventually cause bearing and seal damage.
For quick response, locate the control valve as close as
possible to the FMBS-875.
Align air inlet port to the six o’clock down position to
allow condensation to drain out of the exhaust port.

2FORM NO. L-20206-A-0601
LUBRICATION
Pneumatically actuated devices require clean, pressure regulated, and lubricated air for maximum performance and
long life. The most effective way to lubricate the FMBS-875 is with an air line lubricator, which injects an oil mist into
the air chamber.
Locate lubricator above and within ten feet of the FMBS-875, and use a low viscosity oil such as SAE-10.
NOTE: Synthetic lubricants are not recommended.
LUBRICATOR DRIP RATE SETTINGS
1. Determine CF(See Table 1).
2. Multiply CFby 1.32 ( the Average Air Chamber
Volume) to determine cu. in. / min..
3. Divide cu. in. / min. by 1728 to determine cu. ft. /
min. (SCFM).
4. Multiply cu. ft. / min. (SCFM) by cycles per minute.
NOTE: Nexen recommends one drop of oil every 20
SCFM.
5. Divide twenty by the result of Step 4to determine
time in minutes between drops of oil formed in the
Lubricator Sight Gauge.
SPLINE
Although the Hub Spline has been lubricated at the
factory with a high temperature, anti-seize lubricating
compound, Nexen recommends periodic lubrication of
this component to insure smooth brake engagement and
disengagement.
TABLE 1
0 102030405060708090100
P.S.I.
1
2
3
4
5
6
7
8
C
f
BEARINGS
All bearings are pre-lubricated and sealed, therefore
lubrication of the bearings is not recommended.
NOTE: Brake must be disassembled to lubricate Hub
Spline.

3FORM NO. L-20206-A-0601
TROUBLESHOOTING
MELBORP ESUACELBABORP NOITULOS
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PARTS REPLACEMENT
FRICTION FACINGS
1. Remove Socket Head Cap Screws (Item 14), then
separate Air Chamber and Male Pilot Assembly from
Housing (See Fig. 2).
2. Align Holes of Splined Disc (Item 9) with Flat Head
Machine Screws (Item 12) and remove Machine
Screws (See Fig. 3) holding Split Friction Facing
(Item 11)
NOTE: If removal of Machine Screws (Item 12) is
difficult, strike end of screwdriver with a
hammer to break the crystalline structure of
the thread locking compound before attemp-
ting to remove Machine Screws (Item 12).
3. Remove Split Friction Facings (Item 11).
4. Install new Friction Facings.
5. Apply Loctite®222 or equivalent to threads of
Machine Screws (Item 12) and tighten Machine
Screws to 22 in. lbs. [2.5 N•m] torque.
6. Apply Loctite®222 or equivalent to threads of
Socket Head Cap Screws (Item 14).
7. Using Socket Head Cap Screws (Item 14), Secure
Air Chamber and Male Pilot Assembly to Housing.
8. Alternately and evenly tighten Socket Head Cap
Screws (Item 14) to 27 ft. lbs. [36.7 N•m] torque.
FIGURE 2
FIGURE 3
Socket Head
Cap Screws
(Item 14)
Air Chamber and
Male Pilot Assembly
Housing
Align these
holes with
Machine Screws
(Item 12)
to remove
Machine Screws
and Friction
Facing
(Item 11)

4FORM NO. L-20206-A-0601
HOUSING BEARING REPLACEMENT
1. Remove Socket Head Cap Screws (Item 14), then
separate Air Chamber and Male Pilot Assembly
from Housing (Item 1) (See Fig. 4).
2. Remove Housing Guard (Item 27) (See Fig. 4).
3. Remove Retaining Ring (Item 3 (See Fig. 4).
Special attention should be exercised when
working with Retaining Ring. Always wear
safety goggles when working with spring or
tension loaded fasteners or devices.
4. Fully supporting Housing (Item 1), press Bearing
(Item 2) out of Housing (See Fig. 4).
NOTE: Do not reuse Bearing. Applying force on
inner bearing race to remove bearing held
by outer race causes damage to bearing.
5. Clean Bearing Bore of Housing with fresh safety
solvent.
FIGURE 4
Air Chamber
& Male Pilot
Assembly
Ring
Guard
(Item 27)
Bearing
(Item 2)
Retaining
Ring
(Item 3)
Housing
(Item 1)
Socket Head
Cap Screws
(Item 14)
6. Apply Loctite®601 or equivalent to outer race of
new Bearing, then press new Bearing into Bore of
Housing.
7. Install Retaining Ring (Item 3).
MALE PILOT BEARING REPLACEMENT
1. Remove Socket Head Cap Screws (Item 14), then
separate Air Chamber from Male Pilot Assembly
(See Fig. 5).
2. Remove Retaining Ring (Item 25) (See Fig. 5).
Special attention should be exercised when
working with Retaining Ring. Always wear
safety goggles when working with spring or
tension loaded fasteners or devices.
4. Fully supporting Male Pilot (Item 21), press Shaft
(Item 24) out of Male Pilot (See Fig. 5).
5. Using a Bearing Puller, remove Bearings (Item 20)
(See Fig. 5)
NOTE: Do not reuse Bearing. Applying force on
inner bearing race to remove bearing held
by outer race causes damage to bearing.
6. Clean Bearing Bore of Male Pilot with fresh safety
solvent.
FIGURE 5
Bearings
(Item 20)
Shaft
(Item 24)
Air Chamber
Retaining
Ring
(Item 25)
Male
Pilot
(Item 21)
Socket Head
Cap Screw
(Item 14)
7. Apply Loctite®601 or equivalent to outer race of
one new Bearing, then press one new Bearing into
Bore of Male Pilot. that faces the Air Chamber
(Item 13).

5FORM NO. L-20206-A-0601
PISTON BEARING, COMPRESSION SPRING, AND
O-RING SEAL REPLACEMENT
1. Compress Piston (Item 15) into Air Chamber (Item
13), then remove Retaining Ring (Item 6) securing
Splined Disc (Item 9) inside Piston (See Fig. 6).
Special attention should be exercised when
working with Retaining Ring. Always wear
safety goggles when working with spring or
tension loaded fasteners or devices.
2. Press Splined Disc (Item 9) out of Piston (Item 15)
(See Fig. 6).
3. Slide Piston (Item 15) out of Air Chamber (Item 13)
(See Fig. 7).
4. Remove Compression Springs (Item 17) from
Piston (Item 15), and inspect Compression Springs
for signs of damage.
If Compression Springs show any signs of
wear or damage, they must be replaced.
5. Remove O-ring Seal (Item 16) from Piston (Item 15)
(See Fig. 7).
6. Remove Retaining Ring (Item 3) from Piston (Item
15) (See Fig. 7).
7. Press Bearing (Item 2) out of Piston (Item 15) (See
Fig. 7).
NOTE: Do not reuse Bearing. Applying force to
inner bearing race to remove bearing held
by the outer race causes damage to the
bearing.
8. Clean Bearing Bore of Piston with fresh safety
solvent.
9. Apply Loctite®601 or equivalent to outer race of
new Bearing, then press new Bearing into Piston.
10. Install Retaining Ring (Item 6).
11. Clean O-ring groove of Piston, then apply a thin
coat or O-ring Lubricant to new O-ring Seal (Item 16)
and O-ring contact surfaces of Piston (See Fig. 7).
FIGURE 6
FIGURE 7
Splined
Disc
(Item 9)
Retaining
Ring
(Item 6)
Air Chamber
& Piston Assembly
Air Chamber
(Item 13)
Bearing
(Item 2)
Compression
Spring (Item 17)
Piston
(Item 15)
O-ring Seal
(Item 16)
Retaining
Ring
(Item 3)
12. Install new O-ring Seal (Item 16) (See Fig. 7).
13. Install new Compression Springs (Item 17) (See
Fig. 7)
14. Slide Piston (Item 15) into Air Chamber (Item 13)
(See Fig. 7).
15. Slide Splined Disc (Item 9) into Piston (See Fig. 6).
16. Compress Piston (Item 15) into Air Chamber (Item
13), then replace Retaining Ring (Item 6) (See
Fig. 6).

6FORM NO. L-20206-A-0601
FIGURE 8
Housing
(Item 1)
Housing
Guard
(Item 27)
O-ring
Seal
(Item 23)
Air Chamber
& Piston
Assembly
Shaft
(Item 24)
Spring
Pin
(Item 21)
Socket Head
Cap Screw
(Item 14)
Retaining
Ring
(Item 25)
O-ring
Seal
(Item 22) Bearing
(item 20)
Socket Head
Cap Screw
(Item 14)
Lubricate this
area with
NEVER-SEEZ®.
FMBS-875 REASSEMBLY
10. Lubricate splines of Shaft (Item 24) with NEVER-
SEEZ®, then slide into Air Chamber/Male Pilot
Assembly ((See Fig. 8).
11. Apply Loctite®601 or equivalent to outer race of
new Bearing (Item 20) and press Bearing into Male
Pilot (Item 18).
12. Install Retaining Ring (Item 25) (See Fig. 8).
Special attention should be exercised when
working with Retaining Ring. Always wear
safety goggles when working with spring or
tension loaded fasteners or devices.
13. Apply Loctite®222 or equivalent to threads of
Socket Head Cap Screws (Item 14) securing Air
Chamber/Male Pilot Assembly to Housing (See
Fig. 8).
14. Using Socket Head Cap Screws (Item 14), secure
Air Chamber/Male Pilot Assembly to Housing (See
Fig. 9).
15. Alternately and evenly tighten Socket Head Cap
Screws (Item 14) to 27 ft. lbs. [36.7 N•m] torque.
1. Remove O-ring Seal (Item 22) from Male Pilot (Item
18) (See Fig. 8)
2. Clean O-ring groove of Male Pilot, then apply a thin
coat of O-ring lubricant to new O-ring Seal (Item 22)
and O-ring contact surfaces of Male Pilot (See Fig. 8).
3. Install new O-ring Seal (Item 22).
4. Remove O-ring Seal (Item 23) from Air Chamber
(Item 13) (See Fig. 8)
5. Clean O-ring groove of Air Chamber, then apply a
thin coat of O-ring lubricant to new O-ring Seal (Item
23) and O-ring contact surfaces of Air Chamber
(See Fig. 8).
6. Install new O-ring Seal (Item 23).
7. Align Spring Pin (Item 21) with hole in Cylinder, and
slide Male Pilot (Item 18) into Air Chamber (Item 13)
(See Fig. 8).
8. Apply Loctite®222 or equivalent to threads of
Socket Head Cap Screws (Item 14) securing Male
Pilot (Item 18) to Air Chamber (Item 13) (See Fig. 9).
9. Tighten Socket Head Cap Screws (Item 14) to 27 ft.
lbs. [36.7 N•m] torque.

7FORM NO. L-20206-A-0601
REPLACEMENT PARTS
The item or balloon number for all Nexen products is used
for part identification on all product parts lists, product
price lists, unit assembly drawings, bills of materials, and
instruction manuals.
When ordering replacement parts, specify model
designation, item number, part description, and quantity.
Purchase replacement parts through your local Nexen
Distributor.
PARTS LIST
ITEM DESCRIPTION QTY
1 Housing 1
2 Ball Bearing 2
3 Retaining Ring (Int) 2
6 Retaining Ring (Ext) 1
9 Splined Disc 1
10 Slotted Spring Pin 3
11 Friction Facing 1
12 Flat Head Screw 6
13 Air Chamber 1
14 Socket Head Cap Screw 8
15 Piston 1
16 O-Ring Seal 1
ITEM DESCRIPTION QTY
17 Compression Spring 12
18 Male Pilot 1
19 Retaining Ring (Int) 2
20 Ball Bearing 1
21 Slotted Spring Pin 1
22 O-Ring Seal 1
23 O-Ring Seal 1
24 Shaft 1
25 Retaining Ring (Ext) 1
26 Key (Not Shown) 1
27 Housing Guard 1
FIGURE 9
FMBS-875 Exploded Parts Drawing
1
2
327
9
6
21
18
2
12 24
10
14
19 20
25
19
20
22
16
15
17
3
23
14
13
11