Kinetics Model HSR HVAC fan thrust restraints are spring-based devices engineered to counteract the discharge force generated by fans and air-handling equipment. Installed in pairs across the flexible duct connection, they help control equipment movement while maintaining the intended vibration-isolation performance.
HSR restraints are recommended for fan heads, suspended fans, and base-mounted or suspended air-handling units operating at 2 in. TSP—approximately 500 Pa—or greater. Kinetics Group provides product selection, technical submittals and project support for commercial, healthcare, hospitality, data centre, industrial and infrastructure projects across the UAE, GCC and MENA region.
Engineered for Performance.
Kinetics Model HSR HVAC fan thrust restraints are spring-based devices engineered to counteract the discharge force generated by fans and air-handling equipment. Installed in pairs across the flexible duct connection, they help control equipment movement while maintaining the intended vibration-isolation performance.
HSR restraints are recommended for fan heads, suspended fans, and base-mounted or suspended air-handling units operating at 2 in. TSP—approximately 500 Pa—or greater. Kinetics Group provides product selection, technical submittals and project support for commercial, healthcare, hospitality, data centre, industrial and infrastructure projects across the UAE, GCC and MENA region.
| Selection parameter | Kinetics HSR data |
|---|---|
| Product type | Spring-based HVAC fan thrust restraint |
| Product classification | ASHRAE Type 5 in the Kinetics selection guide |
| Primary function | Counteracts discharge force generated by operating fans |
| Recommended equipment | Fan heads, suspended fans and base-mounted or suspended air-handling equipment |
| Application threshold | 2 in. TSP, approximately 500 Pa, or greater |
| Installation arrangement | Installed in pairs at the fan discharge |
| Rated capacity | 35–1,975 lb / 16–896 kg |
| Rated deflection | 1–2 in. / 25–51 mm |
| Construction | High-deflection, large-diameter, laterally stable steel coil spring with threaded rod and bracket assembly |
| Related equipment | Flexible duct connectors, spring isolators and inertia bases |
Each HSR assembly consists of high-deflection, large-diameter, laterally stable steel coil springs mounted within a threaded rod and bracket assembly. The coil springs are designed to provide stable performance under fan operating conditions, while the threaded adjustment rod allows movement adjustment under normal fan static pressure. The system includes mounting bracket angles, bracket back-up plates, and attachment hardware for fan and ductwork installation.
For HVAC, MEP, and mechanical services projects in commercial buildings, hospitals, hotels, industrial facilities, data centers, and infrastructure developments, HSR Thrust Restraints provide a practical solution for controlling fan thrust, supporting vibration isolation performance, and protecting connected ductwork and equipment assemblies.
Thrust Restraints shall consist of high deflection, large diameter, laterally stable steel coil springs assembled into a threaded rod and angle bracket assembly. Coil springs shall have a lateral spring stiffness greater than 1.0 times the rated vertical stiffness to assure coil stability. Coil springs shall provide a minimum of 50% overload deflection capability to solid and shall be safe when temporarily loaded to solid capacity. Coil springs shall be polyester powder coated for corrosion protection and shall demonstrate successful completion of a 1000 hour salt spray test per ASTM Standard B-117. Thrust Restraints shall feature molded neoprene end load plate assemblies for light capacities or stamped steel end cups for heavier capacities. Thrust Restraints shall include threaded adjustment rod with zinc-plated hardware, and shall include primer painted fan and ductwork mounting bracket angles, bracket back-up plates, and complete fan / ductwork attachment hardware.
Thrust Restraints shall be Model HSR as manufactured by Kinetics Noise Control, Inc.
HSR thrust restraints must be installed in pairs and positioned on the centreline of the fan discharge outlet, bridging the flexible duct connector. The mounting brackets must be secured to the fan and adjoining ductwork or supporting structure in accordance with the approved installation detail.
Final adjustment must be completed while the fan is operating at its normal design static pressure. The selected HSR spring deflection should be coordinated with the equipment’s vibration isolators so the thrust-restraint assembly does not short-circuit the isolation system.
For floor-mounted fans, HSR restraints may be coordinated with a concrete inertia base and spring vibration isolators. Product selection and installation must be based on the fan arrangement, discharge force, operating weight, total static pressure and specified isolator deflection.
