Hilti SIW 10-22 3/4 in High-Torque Cordless Impact Wrench

The Hilti SIW 10-22 is a high-torque cordless impact wrench with a 3/4 in through-hole anvil and friction ring, 850 and 1600 Nm maximum torque values and 2000 Nm nut-busting torque. The tool body weighs 2.9 kg and measures 217 x 86 x 235 mm, so it brings heavy bolting capability to a cordless tool a technician can carry up a scaffold.

Heavy bolting and loosening rusted fasteners without a compressor

Applications listed by Hilti include bolting steel for primary and secondary structures, handrails, racking and machinery with high-tensile bolts up to M30, loosening large rusty bolts for maintenance, operation and repair work, setting large HUS anchors in concrete (10 to 16 mm), lag bolting in wood (12 to 20 mm) and bolting structural steel connections and pipe flanges with 1/2 to 1 1/8 in structural bolts.

Two speed settings let the operator move between heavy and lighter work: mode I runs 0 to 1,000 rpm no-load with up to 2,000 impacts per minute, and mode II 0 to 1,250 rpm with up to 2,500 impacts per minute. A brighter LED light, lower vibration and a robust brushless motor are the manufacturer’s listed benefits.

Technical specifications

Flange bolting, torque control and ordering checks

For pipe flanges and structural connections that carry a bolting specification, use the wrench to run the nuts down and finish with a calibrated torque method. The Hilti data carries the warning that impact wrenches must not be used where an exact or maximum torque is specified, because of the risk of over-tightening and damage to the screw or workpiece.

Enquire with the battery and charger you need, impact-rated 3/4 in sockets and, if you want a quick-lock socket retention, ask about the SIW 20-22 which Hilti supplies with its Quick lock system. Compare torque against the bolt grade and diameter, and remember the 2000 Nm figure is a nut-busting value for breaking loose fasteners rather than a tightening value.

Hilti impact wrench range by anvil and torque

Maximum torque values are quoted as printed on the Hilti UAE pages, where footnotes define the test condition of each figure.

Putting the SIW 10-22 into service on site

Before the first job, read the operating instruction and check that the battery pack and charger supplied for the tool match the 21.6 V rating shown in the data above. Inspect the 3/4 in anvil and locking ring for damage, then fit only impact-rated sockets of the correct drive size. A worn or hand-tool socket can split under impact loading, so keep standard chrome sockets out of the impact wrench kit entirely.

Run the wrench briefly with no load in each speed mode so the operator becomes familiar with the difference between mode I and mode II before reaching a live flange or a beam connection. On scaffolds and access platforms, plan how the tool will be tethered or carried, and agree with the site supervisor how bolts will be marked once they have been run down and then torque-checked.

Choosing the right mode and socket for each joint

Lighter fasteners, anchors and lag bolts usually call for the lower mode so the nut is not driven past the point the joint needs. The higher mode is better kept for running long threaded sections and breaking loose seized hardware during shutdown work. Match socket depth to the stud projection on each flange, and avoid long extensions where possible, because every adapter between anvil and nut absorbs part of the impact energy and makes results less consistent.

Working in Omani heat, dust and coastal humidity

Construction sites, refineries and port facilities in Oman and the wider GCC expose cordless tools to strong sun, fine sand and salt-laden air. The operating temperature range printed in the Hilti data should be respected; tools and batteries left on a steel deck or inside a closed vehicle in summer can exceed it quickly. Store the wrench and packs in shade, let a hot battery cool before charging, and avoid charging in direct sunlight.

Fine dust drawn into a tool shortens its life. Blow off the housing with dry, low-pressure air at the end of a shift, keep the anvil area clean and lightly protected against corrosion near the coast, and wipe battery contacts before the pack is fitted. The 100 dB(A) sound pressure figure means hearing protection should be part of the standard kit for every operator.

Routine care and inspection between jobs

Set up a simple check sheet for each tool: housing condition, anvil and ring wear, battery condition, charger cable and plug, and any change in sound or vibration during use. Remove the tool from service if impacts feel weak or irregular and return it for inspection rather than continuing on structural bolting.

Because impact output is not a controlled tightening value, keep calibrated torque wrenches or a tensioning method on hand for final make-up of specified joints, and record final torque on the job documentation. Rotating batteries between tools and keeping spare packs charged in a cool site office helps crews keep bolting work moving through long shifts.

Documents and quotation

The attached PDF is the manufacturer’s operating instruction for the SIW 10-22 in several languages, and it carries the safety instructions and the technical data quoted above. Item numbers, kit contents and voltage or plug versions change, so confirm them against the Hilti product page and in your enquiry to Seven Star LLC, an independent Muscat supplier. See the Material Handling & Lifting Equipment category for other fastening equipment.