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HAT 28

Original operating instructions

Information about the operating instructions

About these operating instructions

  • Warning! Read and understand all accompanying documentation, including but not limited to instructions, safety warnings, illustrations, and specifications provided with this product. Familiarize yourself with all the instructions, safety warnings, illustrations, specifications, components, and functions of the product before use. Failure to do so may result in electric shock, fire, and/or serious injury. Save all warnings and instructions for future reference.
  • Image alternative products are designed for professional users and only trained, authorized personnel are permitted to operate, service and maintain the products. This personnel must be specifically informed about the possible hazards. The product and its ancillary equipment can present hazards if used incorrectly by untrained personnel or if used not in accordance with the intended use.
  • The accompanying documentation corresponds to the current state of the art at the time of printing. Please always check for the latest version on the product’s page on Hilti’s website. To do this, follow the link or scan the QR code in this documentation, marked with the symbol Image alternative.
  • Ensure that these operating instructions are with the product when it is given to other persons.

Explanation of symbols used


Warnings alert persons to hazards that occur when handling or using the product. The following signal words are used:
  • Draws attention to imminent danger that will lead to serious personal injury or fatality.
  • Draws attention to a potential threat of danger that can lead to serious injury or fatality.
  • Draws attention to a potentially dangerous situation that could lead to personal injury or damage to the equipment or other property.

Symbols in the documentation

The following symbols are used in this document:
Image alternative Read the operating instructions before use.
Image alternative Instructions for use and other useful information
Image alternative Dealing with recyclable materials
Image alternative Do not dispose of electric equipment and batteries as household waste

Symbols in the illustrations

The following symbols are used in illustrations:
Image alternative These numbers refer to the corresponding illustrations found at the beginning of these operating instructions
Image alternative The numbering reflects the sequence of operations shown in the illustrations and may deviate from the steps described in the text
Image alternative Item reference numbers are used in the overview illustrations and refer to the numbers used in the product overview section
Image alternative This symbol is intended to draw special attention to certain points when handling the product.

Product-dependent symbols

Symbols on the product

The following symbols can be used on the product:
Image alternative Wear a hard hat
Image alternative Wear eye protection
Image alternative Wear protective gloves

Product information

Image alternative products are designed for professional users and only trained, authorized personnel are permitted to operate, service and maintain the products. This personnel must be specifically informed about the possible hazards. The product and its ancillary equipment can present hazards if used incorrectly by untrained personnel or if used not in accordance with the intended use.
The type designation and serial number are printed on the rating plate.
  • Write down the serial number in the table below. You will be required to state the product details when contacting Hilti Service or your local Hilti organization to inquire about the product.
    Product information
    Pull-out tester
    HAT 28
    Serial no.


Safety instructions

Basic information concerning safety Image alternative WARNING! Read all safety precautions and other instructions. Failure to observe the safety instructions and other instructions can result in damage to the tool and/or serious injury.
Keep all safety precautions and instructions for future reference.
Proper preparation of the working area
  • Keep your workplace clean and well lit. Cluttered or poorly lit workplaces invite accidents.
  • Wear personal protective equipment and always wear protective goggles.
  • It is recommended that rubber gloves and non-skid shoes are worn when working outdoors.
  • Keep children clear. Keep everyone clear of your work zone.
  • When working on walls or ceilings, make sure that the surrounding work area is secured. Falling objects or tools could cause serious injury.
  • Avoid unusual body positions. Maintain firm footing and balance at all times. This will give you better control of the product in unexpected situations.
General safety measures
  • Use product, accessories, insert tools, etc. in accordance with these instructions. Take the working conditions and the work to be performed into account. Use of equipment for applications other than those intended can result in hazardous situations.
  • To reduce the risk of injury, use only genuine Hilti tools and accessories.
Requirements to be met by users
  • Follow the instructions concerning care and maintenance.
  • Never tamper with or modify the power tool in any way.
  • The tool is intended for professional use. The tool may be operated, serviced and repaired only by authorized, trained personnel. This personnel must be specially informed of any possible hazards.
  • Do not operate the machine if your full attention is not on the job.


Product overview

The composition of shipments can vary.
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  1. Grip
  2. Crank
  3. Coupling
  4. Pressure gauge
  5. Tester housing
  6. Load distribution bridge
  7. Swiveling feet
  8. Adapter X-IE
  9. Slotted button adapter
  10. Threaded button adapter
  11. Scaffold ringbolt adapter
  12. Button adapter
  13. Threaded-rod adapter
  14. Threaded-rod legs
  15. Loading claw foot
  16. Spacer, small
  17. Spacer, large

Intended use

The product described is an application-specific system for testing fasteners. It consists of a mechanical screw jack passing through a hydraulic load cell which directly measures the load applied to the fastener and shows this read-out on the pressure gage.

There is a range of HAT 28 kits. These kits have been specially assembled for testing most small and medium-size fasteners.

Items supplied

Pull-out tester, operating instructions
Other system products approved for use with this product can be found at your local Hilti Store or at:

Overview of spacers for the stud welding application

Stud length (effective thread length)
Spacer used
≤ 25 mm
No spacer needed.
≤ 38 mm
Use small spacer.
≤ 50 mm
Use large spacer.
≤ 100 mm
Use large spacer and small spacer together.

Technical data

HAT 28 M
Maximum displacement
50 mm
50 mm
50 mm
Displacement indicator scale
Weight (without load distribution bridge)
2.5 kg
2.5 kg
2.5 kg
Weight (with load distribution bridge)
4 kg
4 kg
Effective span of load distribution bridge
40 mm
118 mm
118 mm
Test load
Pressure gage 1
0 kN … 5 kN
0 kN … 5 kN
0 kN … 20 kN
Pressure gage 2
0 kN … 25 kN
Ambient temperature for operation
−17 ℃ … 60 ℃
−17 ℃ … 60 ℃
−17 ℃ … 60 ℃
Storage temperature
−20 ℃ … 70 ℃
−20 ℃ … 70 ℃
−20 ℃ … 70 ℃

HAT 28 E
Maximum displacement
50 mm
50 mm
Displacement indicator scale
Weight (without load distribution bridge)
2.5 kg
2.5 kg
Weight (with load distribution bridge)
4.5 kg
Effective span of load distribution bridge
207 mm
40 mm
Test load
Pressure gage 1
0 kN … 30 kN
0 kN … 30 kN
Pressure gage 2
Ambient temperature for operation
−17 ℃ … 60 ℃
−17 ℃ … 60 ℃
Storage temperature
−20 ℃ … 70 ℃
−20 ℃ … 70 ℃


Basic test procedure

The commonly used test procedure is described below

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  1. The load distribution bridge is already mounted on the tester. For HAP 2.5 tests, secure the HAP 2.5 load distribution bridge. Be sure to use longer screws (40 mm) to secure this bridge.
  2. Install the appropriate adapter on the fastener to be tested.
    • (1)
      Use of directly engaged adapters
    • (2)
      Use of button adapters with spacer
  3. Application 1: Pass the adapter through the bridge and engage the head centered in the loading claw foot of the tester.
  4. Application 2: Push the spacer on to the button adapter. Pass the head of the spacer through the bridge and engage the head centered in the loading claw foot of the tester.
  5. Turn the tester to a position in which the pressure gage is easy to read.
  6. Adjust the length of the threaded legs to have all three legs in contact with the supporting surface and have the pull-out movement along the axis of the fastener and parallel to the threaded legs.
    Any misalignment of the tester set-up will result in damage to the test rig.
    Make sure that in the pull-out test, the tensile force is applied exclusively via the crank.
    Load testing with application of the load via the threaded legs is a misuse and can damage the tester or lead to incorrect test results.
  7. Set the red pointer of the gage to zero. Hold the tester by the grip while increasing the load on the fastener by turning the crank clockwise.
    Do not relax your firm hold on the grip as long as the fastener remains under load. As the load on the fastener increases, observe the reading shown by the displacement scale on the pull-out tester. Signs of failure of the fastener can be detected by comparing the current reading on the displacement scale with the original reading.
  8. Increase the load until the minimum specified load is attained.
  9. To relieve the load on the fastener, turn the crank counter-clockwise and push it down until the original state is reached.
  10. Now remove pull-out tester and adapter.

Use of the spacer

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The spacer is used with the button adapters (threaded (A) or slotted (B) ) or for direct testing (without button adapter) of fasteners with a diameter of 16 mm. It consists of a cylindrical section and an M12 threaded rod to which an M12 adapter is mounted. The cylindrical section has a slot into which the adapter for the fastener to be tested fits.
One of the load distribution bridges is required for every test using the spacer.
In exceptional cases (e.g. fasteners on steel (X-CRM)), the adapters (M4, M5, M6, M8, M10, M12) can also be used without the spacer for testing.
Under these circumstances, the procedure is the same as that described in the section below for testing with adapters (M12, M16, M20).
Invariably, however, the desired results can be obtained only if the fastener was set correctly prior to installation of the adapter.

Use of the threaded button adapters (M4, M5, M6, M10, M12)

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For testing threaded fasteners (for example stud anchors, threaded stud fasteners).
As a rule, an M16 nut or bolt head fits directly into the loading claw foot without the need for a threaded button adapter. In exceptional cases (e.g. X-CRM fastener on steel), the tester can be used with the M4, M5, M6, M8, M10 or M12 threaded adapters without spacer or load distribution bridge. Remove the tester from the bridge by removing the 4 mm screws that secure the tester to the bridge. Screw the adapter on to the projecting thread of the fastener and slip the loading claw foot of the tester underneath the flange of the threaded button adapter
If the projecting threaded length is long enough, the fastener can be tested without removal of the fastened item. In this case, however, the load possibly applied to the fastener by the fastened item has to be taken into account (e.g. deadweight), because it acts on the fastener in addition to the load applied by the pull-out tester and increases the probability of fastener failure under test.
When installing the adapter, make sure that a full-surface connection is established between adapter and threaded head.

Use of the slotted button adapter (4.5 mm, 5.5 mm, 6.5 mm, 8.5 mm, 10.5 mm, 12.5 mm)

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For testing fasteners that require a connection to be made to the bolt or anchor head.
Fasteners achieve the desired / required load values only if specified tightening torques, if applicable, were complied with on installation. The 6 slotted button adapters are suitable for testing fasteners in the 4 to 12 mm diameter range.
These adapters are fitted under the head of the bolt or anchor in place of the item usually fastened. They can also be used to test sleeve anchors. In the latter case, however, after being set correctly the anchor has to be backed off slightly to accommodate the adapter. After being correctly retightened with the adapter in position, the anchor can be tested.
This method is not recommended, however, because slackening the anchor can reduce its load value.
Make sure that the adapter is not damaged by being pressed against an uneven surface. We recommend inserting a large washer or a steel plate between the adapter and the surface.

Use of the threaded rod adapters (M5, M6, M8, M10)

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The adapters for M5 and M6 are primarily for testing wall ties.
On account of their special shape, the M5 to M10 adapters can be used without the button adapter

Use of the threaded rod adapters (M12, M16, M20)

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For testing anchors with external thread or internal thread.
For testing an anchor with external thread, the adapter is screwed on to the correctly installed anchor. Screw-in depth: at least equal to thread diameter. The adapter can then be connected directly to the tester.
For testing an anchor with internal thread, a threaded rod is first screwed into the anchor. Then the adapter is screwed on. Screw-in depth: at both ends at least equal to the thread diameter. The adapter can then be connected directly to the tester.

Use of the adapter for X-IE

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  1. Remove the thermal insulation around the fastener.
  2. Install the pull-out tester together with the adapter. Slip the adapter over the head of the insulating element between the two plates of the X-IE adapter in such a way that the shank of the insulating element engages completely in the hole in the bottom plate.
    The threaded legs have to be set to an adequate length to facilitate testing.

Testing in restricted spaces

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  1. Unscrew the crank grips.
  2. You can now turn the crank with a 22 mm ratchet (supplied as part of each kit).
    • This facilitates operation when working close to a wall, for example, where there not enough space to turn the crank.

Test of scaffold anchorages

Basic configuration (HAT 28 master kit)

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  1. Unscrew the swiveling feet from the threaded-rod legs.
  2. Remove the threaded-rod legs.
  3. Screw the 100-mm hex legs into the bridge and tighten until hand-tight.
  4. If necessary, screw the 50-mm hex legs into the 100-mm hex legs and tighten until hand-tight.
  5. Screw the swiveling feet to the ends of the legs.
  6. Check that the pin of the ringbolt adapter is secured with the chain to the adapter itself.
  7. Screw an M12 threaded button adapter or the M12 locking adapter on to the threaded rod of the ringbolt adapter and engage the latter in the loading claw foot of the tester.
  8. If the surface is uneven, compensate by precision-adjusting the legs before proceeding with the test.

Use of the scaffold ringbolt adapter

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  • Remove the pin from the adapter and position the adapter over the scaffold ringbolt. Reinsert the pin into the adapter and through the scaffold ringbolt.

Bridge installation, HAT KIT HAP 2.5

To test the HAP 2.5 you need the HAT KIT HAP 2.5
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  1. Lay the HAT 28 on its side.
  2. Using the screwdriver supplied, remove the two hex socket screws (length with head 35 mm) that connect the HAT 28 to the standard bridge.
    To avoid loss of the screws, insert them into the holes provided for the purpose in the case.
  3. Lay the standard bridge in the case of the HAT 28.
  4. Remove the large bridge from the case of the HAT KIT HAP 2.5.
  5. Lay the large bridge on its side.
  6. Remove the two longer screws (length with head 50 mm) from the case of the HAT KIT HAP 2.5.
  7. Using the screwdriver, screw the HAT 28 with these longer screws to the HAT KIT HAP 2.5.
    When tightening the screws, make sure that the HAT 28 is seated flat with the silver ring on the bridge.
    If this is not the case, the screws or the thread in the tester could be damaged.
    Also make sure that the opening in the HAT 28 is aligned with the opening in the bridge. Otherwise the tester cannot be used.
  8. Using the screwdriver, tighten the screws until the tester no longer wobbles.
    To avoid damaging the aluminum housing, do not overtighten the screws.

HAP 2.5 tests

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  1. Using the pins and holes in the legs, set the large bridge to the correct height.
    The bridge must be parallel with the working surface.
    At maximum load, the adapter must remain out of contact with the bridge.
    The power cord experiences considerable deformation during the test, so it is important to keep checking repeatedly that the adapter remains out of contact with the bridge.
    If this happens, adjust the legs accordingly.
    Also remember the HAT 28's maximum working travel of 45 mm.
  2. Remove the pin from the adapter.
  3. Position the connecting disk inside the adapter.
  4. Re-insert the pin into the adapter through the connecting disk.
  5. Pass the power cord of the HAP 2.5 over the connector disk.
  6. Push the pin back into the adapter.
    Testing the HAP 2.5 without use of the connecting disk leads to serious damage to the power cord of the HAP 2.5. If this happens the HAP 2.5 can no longer be used and must be disassembled.
    If the HAT 28 will subsequently be used with the small bridge, remove the large bridge and the long screws. In this process support the HAT 28 again so that it cannot tip over and damage the screws.

Test of welded studs

The description of the general test setup is in the section headed: Basic test procedure.
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  1. Screw a threaded button adapter on to the F‑BT stud.
  2. Engage the latter in the loading claw foot of the tester.
  3. If necessary, for a long stud use a spacer see the overview of spacers.

Care and maintenance

  • Carefully remove stubborn dirt from the tool.
  • Use only a slightly damp cloth to clean the casing. Do not use cleaning agents containing silicone as these can attack the plastic parts.
  • Check all visible parts and controls for signs of damage at regular intervals and make sure that they all function correctly.
  • Do not operate the product if signs of damage are found or if parts malfunction. Have it repaired immediately by Hilti Service.
  • After cleaning and maintenance, fit all guards or protective devices and check that they function correctly.
To help ensure safe and reliable operation, use only genuine Hilti spare parts and consumables. Spare parts, consumables and accessories approved by Hilti for use with the product can be found at your local Hilti Center or online at:
Refilling with oil
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  • Frequent removal and reconnection of the pressure gage causes the oil level in the reservoir to drop. In extreme cases this can result in the volume of oil dropping below the level necessary for the pressure gage to show a correct reading.
    Technical data
    > 6 mm … < 15 mm
  • When this happens, it is advisable to bring the tester to a Hilti repair workshop for checking and refilling with oil.

Transport and storage

  • Store the product in a dry place, where it cannot be accessed by children or unauthorized persons.
  • Check the product for damage before use after long periods of transport or storage.


Image alternative Most of the materials from which Hilti tools and appliances are manufactured can be recycled. The materials must be correctly separated before they can be recycled. In many countries, your old tools, machines or appliances can be returned to Hilti for recycling. Ask Hilti Service or your Hilti representative for further information.
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  • Do not dispose of power tools, electronic equipment or batteries as household waste!

Manufacturer’s warranty

  • Please contact your local Hilti representative if you have questions about the warranty conditions.

Further information

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For more information on operation, technology, environment and recycling, follow this link:
This link is also to be found at the end of the documentation, in the form of a QR code.