The ST-IW4040 is a compact, high-performance ½″ drive air impact wrench is Designed for operations in confined or restricted working areas, it features a “stubby” body design (overall length of just ~110 mm / 4.33″) while delivering a maximum torque output of 678 Nm (≈ 500 ft-lb).
Features
:- Stubby overall length (~110 mm / 4.33″)-ideal for tight access points.
- ½″ square drive for standard sockets and tool interchangeability.
- Maximum torque: 678 Nm (500 ft-lb) high capability in its size class.
- Free speed: ~9,500 rpm (as per the catalogue listing) for rapid operation.
- Forward/Reverse lever switch for one-hand operation.
- Three-position torque (and/or speed) setting mechanism to adjust output as needed.
- Protective rubber sleeve (on housing) for durability and operator comfort.
- Rear or handle-exhaust design (depending on model) to help keep work environment clear of air blowback.
- Air inlet: ¼″ PT; recommended hose size: 3/8″ I.D. (for adequate airflow) per spec sheet.
Applications
:- Automotive service and repair (engine bays, wheel wells, under lifts) where space is limited and a powerful impact tool is needed.
- Industrial maintenance and production operations involving large bolts or nuts (for example M16 size or larger) with limited clearance.
- Equipment servicing such as hoists, paint tanks, band saw machines, air tapping machines—any situation where large fasteners must be removed or installed in tight spots.
- Construction or mechanical environments where heavy duty fastening is required but bulk and length of traditional full‑size wrenches would inhibit access.
- Maintenance of manufacturing lines, conveyors, heavy machinery where speed and torque are needed in constrained spaces.
- Any workshop or field‑service scenario where one‑hand operation, forward/reverse switch, multiple torque settings (three‑position torque setting mechanism) are advantageous.
Usage
:- Connect the tool to a properly rated compressed‑air supply per the manufacturer’s specification (check air pressure, hose size, consumption). For ST‑IW4040: 1/4" air inlet, 3/8" hose recommended.
- Choose the correct socket (1/2″ square drive) and ensure it’s impact‑rated for durability under high torque.
- Set the torque setting (three‑position torque setting) if the tool supports selectable torque. The ST‑IW4040 has a three‑position torque setting mechanism.
- Position the socket squarely on the fastener; align, engage, then use the trigger to apply torque. For loosening, switch to reverse and let the jumbo‑hammer mechanism break free the bolt/nut.
- Because this is a stubby impact wrench designed for limited space, you can reach into tight engine bays, machine frames, under equipment, where standard length tools can’t fit.
- After use, release trigger, remove socket, check fastener seating and torque if required. Disconnect air hose if the tool will be idle or for maintenance.
- Ensure proper PPE: eye protection, hearing protection (impact tools are loud), gloves if needed. Ensure the working area is secured and the component being fastened or loosened is stab.