You are here: Home > News Overview > News
News: Further links on this topic
PDF Download
SEW-EURODRIVE launches versatile girth gears

Specialist drive engineering company SEW-EURODRIVE has developed a flexible range of girth gears to assist with the transfer of drive torque from the gearmotor to the rotary cylinder, which simplifies manufacturing, transport and installation.


SEW-EURODRIVE general manager for sales and engineering Conrad Pilger notes that the company provides entire drive packages, including girth gears. This includes the basic gear units, as well as the drive pin-ions, a base, housing, and any other parts that are required.


"When supplying girth gears, the process involves machine designers and users, in order to determine the best technical and economic solu-tion for the desired application. SEW-EURODRIVE specialists support the process from the consulting stage right through to the assembly and start-up," he explains.


Girth gears are used to drive large, rotating systems such as dryers, rotary kilns or horizontal mills. They are installed around the circumfer-ence of these systems and transfer the drive torque from the gear motor to the rotary cylinder.


Pilger states that traditional girth gears generally consist of two to four segments that are assembled together for processing. "This requires large and expensive machines for production, handling and heat treat-ment. The size of component parts also creates disadvantages with re-gard to casting and heat treatment."


In contrast, SEW-EURODRIVE girth gears are split into several identical segments in order to keep the component parts short and easy to han-dle. "SEW-EURODRIVE uses Austempered Ductile Iron (ADI) for girth gears, which boasts unmatched tensile strength compared to other ma-terials," he adds.


The decreased size of the girth gear segments reduces the cost for the scrapping of blanks. These blanks can be used without additional weld-ing or oversizing. In addition, the use of ADI lowers the weight of the girth gears and features an above average contact fatigue strength thanks to its cold work hardening properties.


Pilger observes: "These cold work hardening properties, when com-bined with an appropriate girth gear size, allows for a more compact and lighter gear design than traditional solutions. This low weight is im-portant for the handling and assembly of the girth gear, as well as for achieving circumferential velocity."


The segmented design simplifies handling at the construction site. Due to this design, there is no need for special transportation. The segment-ed design also guarantees an initial pitch accuracy of ISO 8, which min-imises the vibrations of the girth gears.


Pilger points out that a benefit of the segmented design is that if a seg-ment or part is damaged, it can easily be replaced without the need for dismantling the entire ring. In addition, with the correct dimensioning, alignment, load and lubrication, an ADI girth gear is almost wear-free.


"The SEW-EURODRIVE girth gears are suitable for use in a variety of sectors. These include; the energy sector, the pulp and paper industry, mining, the steel sector, and the cement industry," concludes Pilger.

The girth gears was launched at Electra Mining, which was hosted at the Nasrec Expo Centre in Johannesburg in September 2014.




Connect with SEW-EURODRIVE on Facebook to receive the company's latest news:


Media Contact

Kelly Farthing

NGAGE Public Relations

Phone: (011) 867-7763

Fax: 086 512 3352 Cell: 079 367 7889




Browse the Ngage Media Zone for more client press releases and photo-graphs at