Enerpac HMT Series User manual

Document Number: L4478
Document Revision: A
Document Revision Date: 25-AUG-2020
Document Language: ENGLISH EN
Operation and Maintenance Manual
HMT Modular Tool
Enerpac HMT
To reduce the risk of injury, user must read and understand this document before use.

L4478_a 1
ABOUT US
Enerpac is a global market leader in high pressure
hydraulic tools, controlled force products, portable
machining, on-site services and solutions for precise
positioning of heavy loads. As a leading innovator with a
110-year legacy, Enerpac has helped move and maintain
some of the largest structures on earth. When safety and
precision matters, elite professionals in industries such as
aerospace, infrastructure, manufacturing, mining, oil & gas
and power generation rely on Enerpac for quality tools,
services and solutions. For additional information, visit
www.enerpac.com.
WARRANTY
Refer to the Enerpac Global Warranty document for terms and conditions of the product warranty. Such warranty
information can be found at www.enerpac.com.
NAMEPLATE
AVAILABLE LANGUAGES
L4478 is available in the following languages, visit www.enerpac.com for a copy.
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Tool
Name
Tool
Number
Location of Manufacture ATEX Rating
Compliance Marking
Warning Alert
Read Owner Manual Symbol Pinch Point
Warning
3D
Barcode
Tool Serial Number
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2L4478_a
Contents
1. SAFETY.......................................................................................................................................................... 3
1.1 SAFETY PRECAUTIONS ...................................................................................................................... 3
1.2 ATEX SAFETY PRECAUTIONS............................................................................................................. 5
2. COMPLIANCE STATEMENT(S) .................................................................................................................... 6
2.1 EU DECLARATION OF INCORPORATION ........................................................................................ 6
2.2 ATEX COMPLIANCE STATEMENT....................................................................................................... 6
3. FEATURES & COMPONENTS ...................................................................................................................... 7
3.1 FEATURE DIAGRAM ............................................................................................................................. 7
3.2 FEATURE DESCRIPTION...................................................................................................................... 9
3.3 HOSE CONNECTION .......................................................................................................................... 11
4. TECHNICAL PRODUCT DATA.................................................................................................................... 12
4.1 HMT WITH HLP CASSETTE DIMENSIONAL CALLOUT ART........................................................... 12
4.2 HMT WITH HLP CASSETTE DIMENSIONAL TABLE.........................................................................12
4.3 HMT WITH HSQ CASSETTE DIMENSIONAL CALLOUT ART .......................................................... 13
4.4 HMT WITH HSQ CASSETTE DIMENSIONAL TABLE........................................................................ 13
5. OPERATION................................................................................................................................................. 14
5.1 INITIAL SETUP .................................................................................................................................... 14
5.2 OPERATING HMT WITH HLP CASSETTE ASSEMBLY ..................................................................... 15
5.3 OPERATING HMT WITH HSQ CASSETTE ASSEMBLY..................................................................... 16
6. STORAGE .................................................................................................................................................... 16
6.1 RECOMMENDED STORAGE .............................................................................................................. 16
7. MAINTENANCE........................................................................................................................................... 17
7.1 GENERAL MAINTENANCE................................................................................................................. 17
7.2 PREVENTATIVE MAINTENANCE ...................................................................................................... 17
7.3 FULL MAINTENANCE......................................................................................................................... 17
8. PARTS LIST ................................................................................................................................................. 24
9. TROUBLESHOOTING ................................................................................................................................. 38

L4478_a 3
1. Safety
1.1 Safety Precautions
Failure to observe and comply with the following
precautions could result in death or serious personal
injury. Property damage could also occur.
• Always wear protective head-wear, ear protectors,
footwear and gloves (at a minimum rigger type
gloves) suitable for safe operation of the tool.
The protective clothing must not interfere with
safe operation of the tool or restrict the ability to
communicate with co-workers.
• Be sure your workplace is safe. Follow the
instructions in your workplace’s standard
operating procedures and be sure to observe all
communicated safety precautions.
• Do not place any part of the body between the
wrench reaction foot and the reaction point.
• Do not place any objects between the wrench
reaction foot and the reaction point. Keep the
hoses away from the reaction points.
• Do not stand in the line of movement of the tool
when it is in operation. If the tool separates from
the nut or bolt during operation it will detach in that
direction.
• Be aware that a nut or bolt that breaks off during
operation of the tool may become a high velocity
projectile.
• Be sure appropriate guards are securely in position
and free from damage.
• Keep your hands away from the fastener being
loosened or tightened. Tightening and loosening
nuts and bolts involves little visible movement.
However, the pressures and loads are extreme.
• Maximum allowable operating pressure for the
HMT-Series torque wrench is 10,000 psi [690 bar].
Do not exceed this pressure setting.
• Always be sure that pump is stopped and
all pressure is fully relieved (0 psi/bar) before
disconnecting or connecting hydraulic hoses. The
sudden and uncontrolled release of pressurized oil
could occur if hoses are disconnected while under
pressure.
• Never attempt to connect or disconnect hoses while
the pump is on and/or the system is pressurized.
• Be certain that all hose couplings are fully
connected at both the pump and wrench ends
before applying any hydraulic pressure. If the
couplings are not fully connected, oil flow will be
blocked, and the wrench could be subjected to
excessive hydraulic pressures. Catastrophic failure
of wrench could result.
WARNING
Read all instructions carefully. Follow all recommended
safety precautions to avoid personal injury as well
as damage to the product and / or damage to other
property. Enerpac cannot be responsible for any
damage or injury from unsafe use, lack of maintenance,
or incorrect operation. Do not remove warning labels,
tags, or decals. In the event that any questions or
concerns arise, contact Enerpac or a local Enerpac
distributor for clarification.
Save these instructions for future use.
If you have never been trained on high-pressure
hydraulic safety, consult your distributor or service
center for information about Enerpac Hydraulic Safety
Courses.
This manual follows a system of safety alert symbols,
signals, words, and safety messages to warn the user of
specific hazards. Failure to comply with these warnings
could result in death or serious personal injury, as well
as damage to the equipment or other property.
The Safety Alert Symbol appears throughout
this manual. It is used to alert you to potential
physical injury hazards. Pay close attention
to Safety Alert Symbols and obey all safety
messages that follow this symbol to avoid the possibility
of death or serious injury.
Safety Alert Symbols are used in conjunction with certain
Signal Words that call attention to safety messages or
property damage messages and designate a degree or
level of hazard seriousness. The Signal Words used in
this manual are DANGER, WARNING, CAUTION, and
NOTICE.
Indicates a hazardous situation that, if not
avoided, will result in death or serious personal injury.
Indicates a hazardous situation that, if not
avoided, could result in death or serious personal injury.
Indicates a hazardous situation that, if not
avoided, could result in minor or moderate personal
injury.
Indicates information considered
important, but not hazard related (e.g. messages related
to property damage). Please note that the Safety Alert
Symbol will not be used with the signal word.
DANGER
WARNING
CAUTION
NOTICE

4L4478_a
• Never apply more hydraulic pressure to any tool,
hose, fitting or accessory than the maximum
allowable pressure as stated in the manufacturer’s
specifications. The system operating pressure
must not exceed the pressure rating of the lowest
rated component in the system.
• Be sure the operator has completed safety induction
training, specific to the work surroundings. The
operator should be thoroughly familiar with the
controls and the proper use of the tool.
• The operator must be of at least the minimum age
required by applicable local regulations, laws and
the facility standard operating procedures.
• Do not abuse or overstress the hoses in any way.
Do not bend the hoses excessively.
• Take every precaution to prevent oil leaks from
occurring. High pressure oil leaks can penetrate
the skin, resulting in serious injury.
• Never strike the tool while it is pressurized or under
load. Components under tension may become
dislodged, allowing them to become dangerous
projectiles. Uncontrolled release of pressurized
hydraulic oil could also occur.
• Avoid striking the tool at any time, even when it
is not pressurized or under load. Striking the
tool could cause permanent damage to wrench
components and may affect the wrench calibration.
• Use only a high quality non-flammable solvent for
cleaning and degreasing parts during wrench repair
procedures. To reduce the risk of fire or explosion,
do not use flammable solvents.
• Be sure to wear proper eye and hand protection
when using solvent. Always follow the solvent
manufacturer’s safety and use instructions and
any additional instructions included in the standard
operating procedures for your work-site. Be certain
there is adequate ventilation when using solvent.
Failure to observe and comply with the following
precautions could result in minor or moderate
personal injury. Property damage could also occur.
• Always carry the wrench by its housing. Never
carry the wrench using the positioning handle. The
handle could break and the wrench could drop
suddenly. The positioning handle is designed only
as an aid to help position the wrench on the bolt
or nut.
• Be sure that backup wrench (on the opposite
end of nut or bolt being tightened or loosened) is
secured so it cannot drop or become disengaged
during bolting procedures.
• Be sure that the hex socket size corresponds to the
size of the fastener being loosened or tightened.
Failure to observe this precaution can result in
the wrench becoming unstable and can lead to
catastrophic failure of the tool.
CAUTION
• Always position the wrench for maximum stability.
Use the positioning handle to properly position tool
during operation.
• Be sure reaction points are adequate for the forces
at work during operation of the tool.
• Be sure the reaction point is of a suitable shape. If
possible, use an adjacent nut or bolt as a reaction
point.
• When the hex socket is placed on the nut or bolt
a gap may exist between the reaction foot and
the reaction point. When the tool is operated the
reaction foot and point will make forceful contact.
Be sure the wrench is stable before applying
hydraulic pressure.
• Provide adequate support in vertical and inverted
applications.
• The torque required to loosen a nut is variable and
may exceed the torque capacity of the wrench.
Never operate the wrench at above 75 percent of
its rated maximum torque when loosening a nut or
bolt.
• Be sure to minimize torsional and bending stresses
in the wrench, the hex socket and any accessories.
• Bolt lubricants and anti-seize compounds will have
a rated coefficient of friction. Be sure to know the
coefficient of friction for the lubricant or anti-seize
compound that is being used. To ensure proper
tightening of nuts and bolts, always use this
coefficient of friction when calculating required
torque values.
Failure to observe and comply with the following
precautions could result in property damage and/or
void the product warranty.
• Never carry the wrench by its hoses.
• Always use Enerpac pumps and hoses.
• Always use Enerpac replacement parts.
• The maximum torque output of the wrench must
always exceed the torque required to loosen or
tighten the nut or bolt.
• Never operate the wrench with a hydraulic supply
connection to the advance side only as this may
damage the internal parts.
• In severe service conditions, be aware that the
wrench must be inspected, cleaned and lubricated
more frequently than normal.
• Check that the swivel post screws are tight prior
to use.
• If oil leakage is present from wrench, replace seals
as required before placing the wrench back into
service.
• If the wrench is dropped from a significant height,
have the tool inspected and checked for proper
operation before placing it back into service.
• Always follow the inspection and maintenance
instructions contained in this manual. Perform
maintenance and inspection activities at the
specified time intervals.
NOTICE

L4478_a 5
1.2 ATEX Safety Precautions
Reducing the Risk of Explosion
Failure to observe and comply with the following
precautions and instructions could result in
explosion and/or fire. Death and/or serious personal
injury could occur.
• To help reduce the risk of explosion, be certain
to use the HMT-Series torque wrench only in the
specific explosive atmospheres for which it has
been tested and certified. Refer to the beginning
of this section for ATEX classification information.
• The HMT-Series torque wrench is generally not
considered as a potential source of ignition.
However, proper operation and maintenance of
the tool is essential in order to help ensure that no
sparks are generated that could cause an ignition
of an explosive gas or dust mixture (which might be
present in the environment). Complete operation
and maintenance instructions must be provided to
all personnel in advance of operating or servicing
the wrench.
• Hot surfaces can be a major source of ignition.
To help prevent the possibility of ignition resulting
from excessive surface temperatures, do not use
the wrench in an environment with an ambient
temperature of above 104°F [40°C].
• Enerpac has designed and constructed the HMT-
Series torque wrench to minimize the possibility
of an incendiary spark that may be caused by the
impact of aluminium components with corroded
steel. However, to reduce the chance of an
incendiary spark, use of the wrench with corroded
steel structures or components should be avoided
whenever possible. Be especially careful to avoid
accidental impacts with the wrench and corroded
steel.
WARNING
To help prevent a mechanical spark hazard,
no components containing a magnesium content
greater than 7.5 percent have been used in the HMT-
Series torque wrench (in accordance with standard EN
13463-1).
• Take extreme care to prevent the HMT-Series
torque wrench from being dropped on the floor or
onto any other metallic surface that might cause
mechanical sparks at impact. Also, take every
precaution to prevent other tools (or other metallic
objects) from dropping onto the HMT-Series torque
wrench.
Electrostatic Discharge
• Electrostatic discharge is a potential source of
ignition and can result in electrostatic build-up
on isolated conductive parts. Isolated conductive
parts create capacitive poles which can become
charged. Electrostatic discharge risk is minimized
by the hydraulic hoses, which have multiple layers
of steel braiding, resulting in electrical continuity
between the torque wrench and the grounded
hydraulic pump.
• Non-conductive polyester labels could be a site
for electrostatic build-up. However, electrostatic
build-up is prevented by the close proximity of the
grounded torque wrench body.
NOTICE

6L4478_a
2. Compliance Statement(s)
2.2 ATEX Compliance Statement
In addition to the CE mark, the Enerpac HMT-Series
torque wrenches carry the ATEX mark and classification:
This classification indicates that the tool is appropriate
for use in a potentially explosive atmosphere.
The testing standards applicable to the HMT-Series
torque wrenches are the standard EN 13463-1:2009,
Non-electrical equipment for use in potentially explosive
atmospheres. Part 1: Basic method and requirements,
and also the draft standard of ISO/IEC 80079-36.
Contact Enerpac if there are any questions regarding the
ATEX classification or questions regarding application
of the HMT-Series torque wrenches in hazardous
environments.
●HMT1500 ●HMT3500 ●HMT7500
Ex II 2 G c T6
2.1 EU Declaration of Incorporation
Enerpac declares that this/ these product(s) has/ have
been tested and conforms to applicable standards and
is compatible to all CE Requirements.
A copy of an EU Declaration of Incorporation is enclosed
with each shipment of this product.
These tools conform with the
requirements for CE.
•HMT1500 •HMT3500 •HMT7500

L4478_a 7
3. Features & Components
3.1 Feature Diagram
Figure 1: Major features and components of HMT Drive Unit
Figure 2: Major features and components of HMT HLP Low Profile Cassette
1
2
3
4
5
6
7
8
1. Swivel Adaptor +
Hose Connections
2. Wrench Body
3. Fixed Pin
4. Rod End
5. Bottom Retaining Pin
6. Lanyard
7. Handle
8. Back Cap
1
6
2
4
5
7
3
8
1
3
4
5
6
2
1. Front Spacer
2. Ratchet Cassette Side Plate
3. Drive Plate
4. Hex Ratchet
5. Drive Pin
6. Bottom Retaining Pin
(part of the HMT Drive
Unit Assembly)
1
2
4
5
3
6

8L4478_a
Figure 3: Major features and components of HMT HSQ Square Drive Cassette
1. Square Drive Cassette Body
2. Drive Pin
3. Body Spacer
4. Drive Plate
5. Reaction Arm Spline
6. Reaction Arm Set Screw
7. Square Drive
8. Reaction Arm
9. Retaining Ring
10. Link Pin Assembly
11. Link Pin Assembly Lanyard
12. Square Drive Socket Attachment
12
8
11
1
2
3
4
5
6
7
9
10
11
6
2
4
5
8
7
3
9
10
12
1

L4478_a 9
3.2 Feature Description
3.2.1 Assembling HLP/ HSQ Cassette
Assemblies onto HMT Drive Unit
The HLP and HSQ cassette assemblies each include
a hook feature as part of the body assembly, this is
inserted around the top retaining pin of the drive. The
cassette assembly rest along the base of drive unit body.
At this point, the bottom retaining pin holes in the drive
unit body and cassette assembly will align, allowing the
bottom retaining pin to be inserted fully to secure the
two together.
3.2.2 Engaging HMT Drive Unit Rod End
with HLP/ HSQ Cassette Drive Plate
Assembly
When assembling the HLP or HSQ Cassette onto the
HMT drive unit body ensure that the rod end of the
drive unit is fully engaged with the drive pin in the drive
plate of the cassette assembly by rotating the ratchet or
square drive ¼ turn back and forth a number of times by
hand until engagement is confirmed.
Failure to ensure correct engagement of
the wrench body and drive plate assembly drive pin
prior to operation will damage the rod end. Resulting
damage will not be covered under warranty.
3.2.3 Using Extended Reaction Arm/
Reaction Paddle with the HMT with HLP
Cassette
To use the HMT with the HLP Cassette, a suitable
reaction surface must be available.
If bolt spacing is such that the reaction surface of the
wrench does not reach a suitable reaction surface such
as an adjacent bolt, use the extended reaction arm or
reaction paddle as depicted. This will allow reaction to
be taken against the side of the flange.
To attach the reaction paddle or extended reaction arm,
remove the standard bottom retaining pin, align the
holes of the reaction paddle or extended reaction arm
with that of the reaction surface of the wrench, insert the
long retraining pin to secure.
Ensure the reaction paddle or extended reaction arm
extends in the appropriate direction: right for tightening;
left for loosening.
CAUTION
Figure 4: Connecting HLP Cassette and HMT Drive
Unit
Figure 5: Connecting HSQ Cassette and HMTDrive
Unit
Figure 6: Installing Reaction Paddle
Figure 7: Installing Extended Reaction Arm

10 L4478_a
3.2.4 Using HSQ Reaction Arm
The HMT with the HSQ Cassette assembly comes
with a reaction arm that is assembled directly onto the
square drive.
Slide the square drive reaction arm over the reaction
arm spline and secured using a socket screw. This is
designed to allow the square drive to move as required
while the reaction stay in place, as shown in Figure 8.
Ensure the reaction arm extends in the appropriate
direction: right for tightening; left for loosening.
Failure to ensure correct engagement of
the wrench body and drive plate assembly drive pin
prior to operation will damage the rod end. Resulting
damage will not be covered under warranty.
3.2.5 Selecting HSQ Cassette Direction
The following diagram illustrates the direction the
square drive should face for loosening and tightening of
a standard right hand fastener:
• For tightening bolts, install the square drive in the
location shown in Figure 9.
• For loosening bolts, install the square drive on the
opposite side of the wrench.
3.2.6 Attaching Handle
Secure the positioning handle with thumb screw or
eyebolt. Handle can be installed on either side of wrench
body (as needed).
Ensure that handle or eyebolt is correctly secured in
place before lifting the wrench.
CAUTION
Figure 8: Installing Square Drive Reaction Arm
Figure 9: Drive Directions for Loosening/ Tightening
Figure 10: Attaching Handle
Left for loosening Right for tightening

L4478_a 11
3.3 Hose Connection
Be sure all hoses and fittings are rated
for at least 10,000 psi [690 bar] operation. Check that
all hydraulic couplings are securely connected before
operating the tool. Failure to observe these precautions
may result in the hoses bursting or disconnecting under
pressure. High pressure oil leakage may also occur.
Serious personal injury could result.
The torque wrench and hydraulic pump are connected
by a 10,000 psi [690 bar] twin-line hose assembly. On
each twin hydraulic hose, one line must be MALE-MALE
and the other line must be FEMALE-FEMALE in order to
ensure a correct interconnection between the pump and
wrench. Ensure the connectors are fully engaged and
screwed snugly together.
NEVER use an even number of hydraulic
twin hoses between the pump and wrench. If so, you
have the high pressure on the retract side and your
wrench is not able to work properly. To avoid tool
malfunction, do not reverse connectors. Do not try to
loosen the swivel assembly at any moment.
Connect hoses to wrench as described in the following
steps:
• Be sure that all pressure in system is relieved and
that pressure gauge indicates zero psi/bar.
• Remove the hose dust caps.
• Connect the hose with the female coupling to the
wrench advance coupling.
• Connect the hose with the male coupling to the
wrench retract coupling.
• At each connection, pull the collar on the female
coupling over the male coupling. Engage threads
and hand tighten the collar.
• Connect the hoses to the pump. Refer to the pump
instruction manual.
WARNING
CAUTION
Figure 11: Hose Connection

12 L4478_a
4. Technical Product Data
4.1 HMT with HLP Cassette Dimensional Callout Art
4.2 HMT with HLP Cassette Dimensional Table
Model Number
HMT1500 HMT3500 HMT7500
Maximum Operating
Pressure
psi 10,000 10,000 10,000
bar 690 690 690
Minimum Torque lbf.ft 154 354 756
Nm 209 480 1,025
Maximum Torque lbf.ft 1,541 3,543 7,562
Nm 2,089 4,804 10,252
Weight Cassette lbs 4.41 8.82 - 11.02 17.63 - 19.84
kg 2.0 4.0 - 5.0 8.0 - 9.0
HMT lbs 2.2 3.97 7.05
kg 1.0 1.8 3.2
Dimensions A inch [mm]
7.23 [183.72] 5.79 [147.12] 12.16 [308.80]
B inch [mm]
1 1⁄16" - 2 1⁄4" [26 - 57] 1 3⁄8" - 3 1⁄8" [35 - 80] 2 3⁄16" - 3 15⁄16" [55 - 100]
C inch [mm]
0.38 [9.75] 0.50 [12.75] 0.64 [16.30]
D inch [mm]
1.2 [31.5] 1.7 [42.0] 2.1 [52.6]
E inch [mm]
1.94 [49.40] 2.58 [65.50] 3.23[82]
F inch [mm]
4.01 [102] 5.35 [136] 6.70 [170.11]
E
D
B
C
F
A

L4478_a 13
4.3 HMT with HSQ Cassette Dimensional Callout Art
4.4 HMT with HSQ Cassette Dimensional Table
Model Number
HSQ1500 HSQ3500 HSQ7500
Square Drive ¾" 1" 1 ½"
Maximum Operating
Pressure
psi 10,000 10,000 10,000
bar 690 690 690
Minimum Torque lbf.ft 154 354 756
Nm 209 480 1,025
Maximum Torque lbf.ft 1,541 3,543 7,562
Nm 2,089 4,804 10,252
Weight HSQ lbs 5.95 9.04 18.08
kg 2.7 4.1 8.2
HMT lbs 2.2 3.97 7.05
kg 1.0 1.8 3.2
Dimensions A inch [mm]
7.28 [184.83] 8.36 [212.25] 9.64 [245]
B inch [mm]
6.45 [163.94] 8.13 [206.60] 10.08 [256.06]
C inch [mm]
2.34 [49.50] 2.58 [65.50] 3.15 [80]
D inch [mm]
1.19 [30.20] 1.52 [38.50] 1.99 [50.50]
E inch [mm]
2.36 [60] 3.07 [78] 4.33 [110]
F inch [mm]
4.33 [110] 5.83 [148] 8.27 [210]
G inch [mm]
3.36 [85.37] 4.36 [110.80] 6.40 [162.65]
C
G
D
E
F
B
A

14 L4478_a
5. Operation
5.1.2 Inspection Before Operation
• Be sure the nut or bolt to be fastened is clean and
free of loose dust or dirt.
• Be sure the nut threads properly engage with the
threads of the bolt, and that cross-threading has
not occurred.
• Be sure that the threads and the bearing surface
are liberally coated with the correct bolt lubricant
or anti-seize compound.
• Make all torque calculations based on the bolt
lubricant’s (or anti-seize compound’s) stated
coefficient of friction. Failure to do so may result in
the required bolt load not being achieved.
• Be sure that the backup wrench (used to keep the
nut or bolt on the opposite end in place) is correctly
positioned and secured.
Be certain that backup wrench is of the
correct size and that there is an adequate abutment
surface. Personal injury could occur if backup wrench
loosens or dislodges during bolting procedures.
WARNING
5.1 Initial Setup
5.1.1 Setting the torque
After determining the desired torque, use the calibration
certificate supplied with your wrench to determine the
pressure that is necessary to achieve that torque.
1. Connect the tool to the power supply and turn the
pump on.
2. Adjust the pressure on the pump as necessary
to set the torque. Refer to pump manufacturer’s
instruction manual.
3. When the desired pressure is reached, cycle the
tool again to confirm that the desired pressure
setting has been obtained.
Figure 12: Using the Pump

L4478_a 15
5.2 Operating HMT with HLP
Cassette Assembly
The position of the tool relative to the nut determines
whether the action will tighten or loosen the nut. The
power stroke of the piston assembly will always turn the
ratchet hex toward the front spacer.
1. Place the ratchet hex on the nut. Make certain it is
the correct size for the nut and that it fully engages
the nut.
2. Position the reaction surface of the wrench against
a suitable reaction surface such as an adjacent nut,
flange or solid system component. Make certain
that there is clearance for the hoses, and swivel
coupling assembly. DO NOT allow the tool to react
against the hoses, or swivel coupling assembly.
If required attach the extended reaction arm or
reaction paddle, as depicted in Figure 13/ 14, to
allow reaction against the side of the flange.
3. Turn the pump on and set up the pre-set pressure
for the correct torque. Use the remote control
advance button to advance the piston assembly.
Ensure that the rod end has engaged with
the drive pin in the HLP cassette assembly prior to use.
4. When the HLP cassette assembly is connected
to the nut and the wrench started, the reaction
surface of the wrench will move against the contact
point and the nut will begin to turn. Once the piston
reaches the end of its stroke, the pressure will rise
rapidly. On the pump use the controls to retract the
tool. There is usually a series of audible clicks as
the tool retracts.
5. Continue this cycling operation of advance and
retract until the nut is no longer turning and the
pump gauge reaches the pre-set pressure.
6. Once the nut stops rotating, cycle the tool one last
time to ensure final torque has been achieved.
CAUTION
Figure 13: Position HMT with HLP Cassette with a
suitable reaction point
Figure 14: Using reaction paddle
Figure 15: Using extended reaction arm

16 L4478_a
5.3 Operating HMT with HSQ
Cassette Assembly
The position of the tool relative to the nut determines
whether the action will tighten or loosen the nut. The
power stroke of the piston assembly will always turn the
square drive toward the body spacer.
1. Before using the HMT drive unit and HSQ cassette
assembly, cycle the wrench two or three times to
ensure that the link is inserted correctly.
2. Select correct socket for bolt to be loosened /
tightened.
3. Ensure the reaction arm contacts a suitable
reaction point at a 90° angle from the square drive,
as per the following image;
4. After having turned the pump on, input the pre-
set pressure for the correct torque, and using the
remote control advance the piston assembly.
Ensure that the rod end has engaged with
the drive pin in the square drive cassette assembly prior
to use.
5. When the socket is connected to the nut and the
wrench started, the reaction surface of the wrench
will move against the contact point and the nut will
begin to turn. Once the piston reaches the end of its
stroke, the pressure will rise rapidly. On the pump
use the controls to retract the tool. There is usually
a series of audible clicks as the tool retracts.
6. Continue this cycling operation of advance and
retract until the socket is no longer turning and the
pump gauge reaches the pre-set pressure.
CAUTION
Figure 16: Position HMT with HSQ Cassette with a
suitable reaction point
7. Once the nut stops rotating, cycle the tool one last
time to ensure final torque has been achieved.
8. To reverse the torque wrench direction, release the
drive retainer and pull out the square drive. Move
the square drive to the opposite side and reinsert
retainer.
6. Storage
6.1 Recommended Storage
Enerpac tools should be stored in a cool, dry place.
Tools should always be cleaned, serviced and lubricated
prior to storage. Ensure that tools are stored in their
designated packing cases.

L4478_a 17
7. Maintenance
7.2 Preventative Maintenance
1. Check tightness of swivel assembly retaining
screws (12) and drive unit body back cap screws
(10) (see Section 7.2).
2. Pressurize the wrench to 10,000 psi [690 bar]
pressure (in both advance and retract), and check
for any signs of leakage.
3. Relieve pressure and disconnect hydraulic hoses.
4. Clean all exposed components with a mild solvent.
7.3 Full Maintenance
7.3.1 Hydraulic Swivel Assembly
Disassembly of Swivel Post and Swivel Assembly
Attachment (Fig 17 + Fig.18)
• Remove the circlip (A) from the top of the swivel
post (E).
• Using a pair of flat blade screwdrivers, gently pry
the swivel assembly (B) from the swivel post (E).
• Remove O-ring (D) from the swivel post (E).
• Remove the socket head capscrews (C) and the
swivel post (E).
• Remove O-rings (F) from the swivel post hydraulic
ports.
• Place the swivel assembly in a vise with soft jaws.
Remove the hydraulic couplings (B1, B2 and B3)
from the swivel assembly (B).
Hydraulic Swivel and Swivel Post Reassembly and
Reinstallation
Hydraulic Fittings:
If removed, reinstall the couplings (B1 and
B3) and adapter (B2) before installing the swivel (B) on
the swivel post (F). Use a vise with soft jaws to hold the
swivel as couplings and adapter are installed.
• Apply Loctite 577 sealant to threads on female
coupling (B3) and adapter (B2). See Fig. 25 for
locations.
• Tighten the couplings (B1 and B3) and adapter
(B2) by hand, until they are each finger tight. Then,
wrench tighten these parts an additional 2 to 3
turns beyond finger tight.
To allow the sealant sufficient time to cure,
wait a minimum period of 3 hours at 68 to 104°F [20
to 40°C], or 6 hours at 40 to 68°F [5 to 20°C] before
pressurizing the wrench.
NOTICE
NOTICE
7.1 General Maintenance
Preventative maintenance can be performed by the
user.
Recommended service intervals are:
• 3 months – Heavy Duty use
• 6 months – Normal use
• 12 months – Infrequent use
Lubrication frequency depends on factors known
only to the user. The amount of contaminants in the
working area is one factor. Wrenches used in a clean
room environment will require less maintenance than
wrenches used outdoors and dropped in loose dirt or
sand.
1. When lubrication is required, lubricate all moving
parts.
2. Springs are used for the drive pawl assembly and
for the accuracy assurance pawl. These springs
can be replaced if necessary.
3. If the piston rod requires disassembly, it is
recommended that the piston rod seals be replaced
at the same time. Seal kits are readily available.
4. Hoses should be checked for cracks and leaks
before, and after each job. Hydraulic fittings can
become plugged with dirt and should be flushed
periodically.
5. Fittings should be kept clean and not allowed to
be dragged along the ground or floor as even small
particles of dirt can cause the internal valves to
malfunction.
6. All structural parts on the tools should be inspected
at least once a year to determine if there are any
cracks, chips, or deformities.
7. Non destructive testing must be carried out if the
tool has been used under severe conditions.
Full maintenance must be performed only by an Enerpac
authorized service center or a qualified and experienced
technician.

18 L4478_a
Swivel Post:
• Apply a small amount of Loctite 243 thread sealant
to the threaded mounting holes in the wrench
housing. See Fig. 11 for locations.
• Install two new O-rings (F) into the ports on the
base of the swivel post (E).
• Place the swivel post (E) onto the wrench (G),
making sure that hydraulic ports are aligned. Be
careful that O-rings (F) do not drop out or become
pinched or cut.
• • Install the degreased socket head capscrews (D)
and tighten to 3.7 Ft.lbs [5.1 Nm].
Swivel Assembly:
• Install a new O-rings (D) into the grooves on the
swivel post (E).
• Coat O-rings (D) with a small amount of silicone
grease. Then, carefully slide the swivel assembly
(B) onto the swivel post (E).
• Reinstall the circlip retainer ring (A).
• Perform hydraulic pressure testing before placing
the wrench into service. Refer to the procedure in
Section 7.2.6
7.3.2 HMT Drive Unit (Fig. 19)
• Disassembly
• Firmly hold the drive unit body (1). Remove bottom
retaining pin (11) and ball end screw (9) from the
drive unit, separate cassette assembly from the
drive unit.
• Unscrew the socket button head cap (18) from the
back cap (2) and remove the bottom retaining pin
lanyard (17).
• Remove the retaining rings (11) and top retaining
pin (6).
• Unscrew the eight socket head cap screws (10)
and remove the back cap (2) and back cap o-ring
(15).
• Unscrew and remove the rod end (4) from the front
of the drive unit body, holding the Piston Rod (3)
with a spanner to prevent rotation.
• Remove piston rod (3) and seals, O-rings and bush
(13, 16, 14, 5) from the drive unit body.
• Check and remove any remaining seals, O-rings or
bush from the drive unit body.
• Remove grub screw (8) and O-ring (20).
• Clean all exposed components with a mild solvent.
• Inspect all parts for damage.
Figure 17: Swivel Post and Swivel Assembly
Figure 18: Exploded Swivel Assembly
B
B2
B3
B1
�
�
✴ Apply Loctite 577 Thread Sealant (thread of B2
and B3)
A
E
D✤
✤D
✤F
C�
✽
G
✽
✽
B
✤ Apply silicone grease
to O-rings.
✽ Apply Loctite 243
Thread Sealant
(inside bolt holes)
󳮢 Tighten to Torque Value
of 5.9 Ft.lbs [8 Nm]