Nexen AIR CHAMP SEM-450A User manual

(i)
Shaft End Mount Element
Models SEM-450A, SEM-600A, SEM-700A
and SEM-800A
FORM NO. L-20105-F-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
Operation ------------------------------------------------------------------------------------------------------------------------------------------ 2
Maintenance and Repair --------------------------------------------------------------------------------------------------------------------- 3
Parts List ------------------------------------------------------------------------------------------------------------------------------------------- 4
Warranties ----------------------------------------------------------------------------------------------------------------------------------------- 5

1FORM NO. L-20105-F-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.
Nexen’s SEM (Shaft End Mount) Element is designed to
mount and operate on shafts ends and motors up to 40
horsepower. When combined with a sheave, the SEM
Element functions as a clutch. With the brake adapter
fastened to a supporting frame, the SEM Element
functions as a brake.
Maintenance is simplified because the single facing and
O-ring are replaceable without removing the SEM
Element from its mounting.
INSTALLATION
SEM ELEMENT
The SEM Element functions either as a clutch or as a
brake. Depending on the mode of operation selected, a
sheave or an adapter is attached to the SEM Elements
pilot with the cap screws (Item 23) supplied. A metric
allen wrench is required.
1 Insert a full length key (supplied by the customer)
into the shaft keyway and slide the SEM Element/
sheave or adapter combination onto the shaft.
NOTE: Shaft insertion must be at least two times
the shaft diameter.
2. Tighten the three set screws (Item 17) (See Table 1
for recommended tightening torques).
3. Secure the brake adapter to a support capable of
sustaining the torque loads produced during braking
(See Figure 1).
TABLE 1
Recommended Tightening Torques
FIGURE 1
Sheave
Brake
Adaptor
-MES A054 -MES A006 -MES A007 -MES A008
wercSteS )71metI( .sbl.tf7.sbl.tf31
*
.sbl.tf32
*
.sbl.tf05
paC wercS )91metI( .sbl.tf11.sbl.tf11.sbl.tf32.sbl.tf14
paC wercS )32metI( .sbl.tf11.sbl.tf32.sbl.tf32.sbl.tf32
NOTE: Metric allen wrenches are required for all cap
screws (Nm = ft.lbs. x 1.3558)

2FORM NO. L-20105-F-0601
AIR CONNECTION
1. Push the flexible tube assembly (Item #25) into the
fitting on the rotary air union (Item #8) until it stops.
2. Connect the 1/8 NPT male fitting end of the tube
assembly to the air supply line. Make sure there is a
slight curve in the tube assembly.
Note: DO NOT USE RIGID PIPE OR TUBING
FOR THIS CONNECTION.
3. To disconnect the tube assembly push in on the
fitting collet and pull out on the tubing.
OPERATION
Before operating, make sure all screws are tightened
securely. See Table 1 for recommended tightening
torques.
Connect the air controls as close to the unit as possible
for fast engagement and disengagement. Use a quick
exhaust valve where long air lines or high cyclic rates are
required.
Pneumatically actuated devices need clean, pressure
regulated air for maximum performance and long life. It is
recommended that a filter, regulator and lubricator be
used on the air line ahead of the air controls.
Check all connections for leaks.
Operating in the Clutch Mode
The drive disc and outer assembly (sheave, housing,
piston, cylinder) rotate independently. When mounted
on a motor shaft, the drive disc rotates continually. The
unit is actuated when air pressure is introduced at the
rotary air union. Air pressure pushes the cylinder/facing
assembly against the drive disc, engaging the outer
assembly. When air exhausts from the cylinder, the return
springs push the cylinder/facing assemblytodisengaged
position.
TABLE 2
LEDOM CSIDEVIRD RETUO YLBMESSA
A054-MESMPR0006MPR0063
A006-MESMPR0054MPR0063
A007-MESMPR0093MPR0003
A008-MESMPR0043MPR0002
Operating in the Brake Mode
When mounted on a continually running shaft, the drive
disc rotates until the unit is actuated. The adapter holds
the outer assembly stationary. Actuating the unit brings
the shaft to a stop.
Maximum Recommended Operating Speed
See Table 2 for maximum recommended operating
speeds for each SEM model.
CAUTION
The outer assembly of the SEM Ele-
ment rotates when operating in the
clutch mode. Install a guard, that will
not restrict the flow of cooling air
around the unit, if it is used where
injury to an operator could occur.

3FORM NO. L-20105-F-0601
FRICTION FACING
1. Inspect the friction facing (Item 5) occasionally and
replace it when it wears to approximately 1/8 inch
thick. The facing is easily replaced without removing
the SEM Element from the shaft.
2. Disconnect the air supply at the rotary air union
(Item 8).
MAINTENANCE AND REPAIR
Periodically inspect all air line connections, making sure they are tightened securely. Inspect all cap screws, making
sure they are tightened to the torques recommended in OPERATION.
NOTE: Metric alien wrenches are required for all screws in the SEM Element.
O-ring (Item 11) Replacement
1. Remove cap screws (Item 19) and slide the piston,
cylinder, rotary air union assembly off the dowel pins.
2. Separate the piston and cylinder.
3. Remove the worn O-ring, lubricate the new O-ring
with O-ring lubricant, and install.
4. Make sure the cylinder bore is clean, and reassem-
ble the piston and cylinder.
3. Remove cap screws (Item 19) and slide the piston,
cylinder, rotary air union assembly off of the dowel
pins (Item 13).
4. Remove machine screws (Item 20) and replace the
worn friction facing. Apply Loctite Threadlocker 271
to the brass machine screws before reinstalling.
O-RING OR ROTARY AIR UNION
If there are noticeable air leaks or loss of torque, determine if the O-rings, hoses, controls or rotary air union are leaking
and replace the appropriate item.
Rotary Air Union Replacement
1. Disconnect the tube assembly (Item 25) by pushing
in on the rotary air union fitting collet and pulling out
on the tube.
2. Remove the screws (Item 10), retaining washer (Item
7), rotary air union (Item 8) and O-ring (Item 9).
3. Lubricate a new O-ring, place it over the new rotary
air union and push the rotary air union into the piston
(Item 51).
4. Replace the retaining washer and screws.
BEARINGS
1. Disconnect the air supply at the rotary air union
(Item 8).
2. Remove set screws (item 17) and slide the SEM
Element off the shaft.
3. Remove retaining ring (Item 16).
4. Press the drive disc (Item 1) out of bearings (Items
14 and 15).
5. Remove retaining ring (Item 22).
6. Push the bearings out of the housing (Item 50).
NOTE: When installing new bearings in the housing,
carefully align each bearing with the housing
bore to prevent slivers of aluminum under the
bearings.
7. Apply Loctite, RC 601, to the outer race of a new
bearing (Item 14) and push it into the housing.
8. Replace retaining ring (Item 22).
9. Support the bearings inner race and press the drive
disc into the bearing. Support the drive disc and
install spacer (Item 2).
10. Apply Loctite, RC 601 to the outer race of a new
bearing (Item 15) and press onto the drive disc and
into the housing.
11. Replace retaining ring (Item 16).

4FORM NO. L-20105-F-0601
REASSEMBLY
1. Install springs (Item 12) on the dowel pins (Item 13).
2. Align the bolt holes in the piston, cylinder, rotary air
union assembly with the tapped holes in the housing
and replace cap screws (Item 19).
3. Tighten the cap screws as recommended in
OPERATION.
PARTS LIST
FIGURE 2
14 22 50 52019
6
51
7
9
8
10
11
1
15
218131221
23
16
17
ITEM DESCRIPTION QTY.
1 Drive Disc 1
2 Spacer 1
51Friction Facing 1
6 Cylinder 1
7 Washer, Retaining 1
81Rotary Air Union 1
9 O-ring 1
10 Screw 3
111O-ring 1
121Spring 3
13 Dowel Pin 1
141Bearing 1
1Denotes Repair Kit Item
2SEM-450A, QTY. 4
ITEM DESCRIPTION QTY.
151Bearing 1
16 Ring, Retaining 1
17 Screw, Set 3
18 Ring, Retaining 1
19 Screw, Cap 6
201Screw, Machine 6
211Bushing, Flanged 3
22 Ring, Retaining 1
232Screw, Cap 6
25 Tube Assembly 1
50 Housing 1
51 Piston 1

5FORM NO. L-20105-F-0601
WARRANTIES
Warranties
Nexen warrants that the Products will be free from any defects in material or workmanship for a period of 12 months
from the date of shipment. NEXEN MAKES NO OTHER WARRANTY, EXPRESS OR IMPLIED, AND ALL IMPLIED
WARRANTIES, INCLUDING WITHOUT LIMITATION, IMPLIED WARRANTIES OF MERCHANTABILITY AND
FITNESS FOR A PARTICULAR PURPOSE ARE HEREBY DISCLAIMED. This warranty applies only if (a) the Product
has been installed, used and maintained in accordance with any applicable Nexen installation or maintenance manual
for the Product; (b) the alleged defect is not attributable to normal wear and tear; (c) the Product has not been altered,
misused or used for purposes other than those for which it was intended; and (d) Buyer has given written notice of the
alleged defect to Nexen, and delivered the allegedly defective Product to Nexen, within one year of the date of
shipment.
Exclusive Remedy
The exclusive remedy of the Buyer for any breach of the warranties set out above will be, at the sole discretion of Nexen,
a repair or replacement with new, serviceably used or reconditioned Product, or issuance of credit in the amount of the
purchase price paid to Nexen by the Buyer for the Products.
Limitation of Nexen’s Liability
TO THE EXTENT PERMITTED BY LAW NEXEN SHALL HAVE NO LIABILITY TO BUYER OR ANY OTHER PERSON
FOR INCIDENTAL DAMAGES, SPECIAL DAMAGES, CONSEQUENTIAL DAMAGES OR OTHER DAMAGES OF
ANY KIND OR NATURE WHATSOEVER, WHETHER ARISING OUT OF BREACH OF WARRANTY OR OTHER
BREACH OF CONTRACT, NEGLIGENCE OR OTHER TORT, OR OTHERWISE, EVEN IF NEXEN SHALL HAVE
BEENADVISEDOFTHE POSSIBILITY OR LIKELIHOOD OF SUCH POTENTIAL LOSS OR DAMAGE. For all of
the purposes hereof, the term “consequential damages”shall include lost profits, penalties, delay images, liquidated
damages or other damages and liabilities which Buyer shall be obligated to pay or which Buyer may incur based upon,
related to or arising out of its contracts with its customers or other third parties. In no event shall Nexen be liable for
any amount of damages in excess of amounts paid by Buyer for Products or services as to which a breach of contract
has been determined to exist. The parties expressly agree that the price for the Products and the services was
determined in consideration of the limitation on damages set forth herein and such limitation has been specifically
bargained for and constitutes an agreed allocation of risk which shall survive the determination of any court of
competent jurisdiction that any remedy herein fails of its essential purpose.
Limitation of Damages
In no event shall Nexen be liable for any consequential, indirect, incidental, or special damages of any nature whatso-
ever, including without limitation, lost profits arising from the sale or use of the Products.
Warranty Claim Procedures
To make a claim under this warranty, the claimant must give written notice of the alleged defect to whom the Product
was purchased from and deliver the Product to same within one year of the date on which the alleged defect first
became apparent.
Nexen Group, Inc.
560 Oak Grove Parkway
Vadnais Heights, MN 55127
800.843.7445
Fax: [phone]
www.nexengroup.com
ISO 9001 Certified