+86 17727725162 jqj014950@topstarltd.com

Home / Low speed 20~28 rpm: Topstar soundproof granulator achieves energy-saving and low-noise processing

Low speed 20~28 rpm: Topstar soundproof granulator achieves energy-saving and low-noise processing

2026/01/23 By le zhan

granulator machine2-2

Noise, dust, and energy waste are not just disruptions in the production process; they represent real costs. When high-speed granulators hum in plastic recycling or production workshops, businesses incur high electricity bills, worker fatigue, and additional cleanup. Topstar’s soundproof granulator, designed with a low-speed (20-28 rpm) cutting approach, effectively addresses this issue. Topstar combines low-speed gear-driven cutting, a hollow-shaft gear motor, and precise acoustic design to effectively reduce noise, conserve energy, and deliver cleaner, higher-quality recycled materials for subsequent processing.

Low Speed ​​20-28 rpm: Advantages of Soundproof Granulator for Cutting Plastic

The function of a soundproof granulator is simple: more precise cutting, not faster. At 20–28 rpm, the rotor (cutter) applies higher torque for a more extended engagement time, altering the material’s behavior during particle size reduction.

Firstly, the low-speed cutting reduces heat generation. High rotational speeds increase friction and shear heat at the cutting interface, softening the polymer, promoting melting, and generating fine powder and dust. For rigid, brittle plastics (such as PC, nylon, and ABS), lower speeds of 20–28 rpm keep the material below its critical softening point during cutting. This results in reduced thermal degradation, improved melt-flow properties during downstream processing, and fewer impurities in the particles.

Secondly, the cut quality is improved. Low-speed, high-torque operation, combined with a gear-driven cutter design and a thicker cutter geometry, produces particles with a more uniform size distribution. This uniformity improves material feeding and metering into the hopper, dryer, and extruder, reducing screen clogging and machine downtime.

Thirdly, noise generation decreases significantly as rotor speed decreases. Aerodynamic and impact noise are proportional to rotational speed and cutting frequency; operating at 20–28 rpm reduces both. In practice, operators will find lower production line noise, less employee fatigue, and a reduced need for large-scale acoustic retrofits.

Hollow Shaft Gear Motor Drive: Compact, Maintenance-Free, and Space-Saving

A key feature of Topstar’s design is its hollow-shaft gear-motor drive. This structure integrates the motor and reduction gears into a single compact component, directly driving the rotor shaft without the separate gearbox and couplings commonly found in traditional pelletizers.

The hollow-shaft gear motor uses sealed, grease-filled bearings and gear sets, designed for lifetime lubrication. This eliminates the need for routine gearbox lubrication and reduces the risk of lubricant contamination, a significant advantage for processing food contact materials or high-purity polymers.

Furthermore, integrating the reduction gears within the motor housing and achieving direct drive via the hollow shaft reduces the overall footprint. For plants requiring a compact unit layout or wishing to install the soundproof granulator near injection molding machines or recycling hoppers, the smaller size simplifies logistics. Simultaneously, the hollow-shaft gear motor provides the high torque required for low-speed, high-resistance cutting while maintaining stable thermal performance. Topstar’s motor selection balances torque output and duty cycle to prevent overheating during continuous operation. These advantages include quieter operation, less vibration transmitted to the frame, and easier direct integration with soundproof enclosures.

TGL-Low-Speed-Sound-Proof-Granulator

Energy Saving and Operating Efficiency

Energy efficiency is more than just an electricity bill. It also determines equipment size, cooling requirements, and long-term operating costs. This soundproof granulator achieves energy savings through several complementary mechanisms.

Higher rotor speeds generate greater air resistance in the cutting chamber and increase friction on the pellet surface, thereby increasing power demand. In contrast, low-speed, high-torque cutting concentrates energy on the mechanical shearing of the material, rather than wasting energy on airflow and heat. The result is a more efficient conversion of electrical input into practical cutting work. In many applications, this translates to a significant reduction in kilowatt-hours per kilogram of recycled plastic compared to conventional high-speed granulators.

Furthermore, matching the rotor geometry, blade profile, and fixed-bed blades is crucial. Topstar engineers designed the cutting head for low-speed operation—a thicker blade body, staggered blade rows, and gear-driven synchronization—ensuring efficient shearing and minimizing rework. Because the rotor is equipped with heavier, stronger blades, grinding is reduced, cutting efficiency is increased, and blade life is extended, reducing energy consumption per cut.

Soundproof Granulator Design: Eliminating Noise Pollution in Factory Workshops

The Occupational Safety and Health Administration (OSHA) and local standards stipulate noise exposure limits; excessive factory noise reduces worker comfort and productivity. Topstar’s soundproof granulators address noise issues on multiple levels, achieving a tranquil granulation process.

The sound energy generated by cutting and impact is closely related to rotational speed. At 20–28 rpm, the primary sources of airborne noise—blade impact, aerodynamic whistling, and bearing harmonics—have significantly lower amplitudes and frequencies than at higher speeds. This reduction in base noise results in smoother acoustic characteristics. Topstar equips low-speed rotors with a carefully designed soundproof enclosure. This enclosure is made of thick steel plates, filled with sound-absorbing foam, and equipped with restraint-layer damping to effectively absorb sound and reduce radiated noise. Elastomer vibration isolation is used at the mounting points to prevent structural noise from propagating to the floor or support platform.

Furthermore, the hollow shaft gear motor provides smooth, continuous torque, avoiding sudden speed changes and coupling backlash, both of which generate pulse noise. The gear profile is precisely cut and balanced to minimize gear squeal. In addition to easier compliance with regulatory standards, a quieter granulator reduces the need for hearing protection and improves communication around the equipment.

Soundproof Granulator Design Eliminating Noise Pollution in Factory Workshops

Achieving Uniform Particles, Minimal Powder, and Long Material Life

The primary function of a plastic granulator is to control particle size and integrity. Topstar’s low-speed plastic granulator offers numerous advantages that translate into superior downstream processing performance.

Low-speed cutting reduces micro-fragmentation and pulverization; thicker blades and gear-driven shearing produce uniform, blocky granules, ensuring a stable feed of material into the dryer and hopper. Uniform granules reduce bridging, improve feeder metering performance, and minimize the generation of fine dust that can lead to flow problems and oxidation.

For complex and brittle materials such as PC, nylon, glass fiber-reinforced composites, and ABS, low-speed, high-torque cutting reduces surface melting and localized heating, thereby preventing stringing or partial melting. This process results in better surface integrity, better filler dispersion, and improved mechanical properties when manufacturers reuse recycled materials in production processes. Furthermore, Topstar offers SKD-11 tool steel or other wear-resistant blade materials suitable for highly abrasive or heavily filled materials. Combined with low-speed grinding, these durable blades extend maintenance intervals and maintain stable particle size control over extended periods of operation.

Injection molding raw materials

Achieving Energy-Saving and Low-Noise Processing

Topstar’s soundproof granulators utilize a low-speed rotor (20-28 rpm) and a hollow-shaft, geared-motor drive, providing a balanced solution for modern plastics processing. It reduces noise pollution, lowers energy consumption, simplifies maintenance, and produces cleaner, more uniform pellets suitable for high-quality recycling and reprocessing.

 

Prev: How to choose the right auto loader to meet the material conveying needs of injection molding?

Next: Not Next

TRENDING POSTS

HOT TOPIC

Get A Quick Quote