In the PC071+PMRV090, the motor drives the PC071 helical pre-stage, where a helical pinion meshes with a helical gear at a ratio of approximately 2.93-3:1. The intermediate shaft connects directly to the worm shaft of the PMRV090 stage. Total combined ratio = i_PC | i_PMRV. Because the helical stage operates at motor speed and carries lower torque, its components can be smaller while still transmitting full motor power efficiently. This architecture yields significantly better overall efficiency than an PMRV-PMRV two-stage configuration for the same total ratio.

Q: Why choose PC071+PMRV090 over a single-stage PMRV at the same ratio?

A: The PC071 helical pre-stage operates at ~97% efficiency, so overall efficiency of PC071+PMRV090 is higher than an equivalent two-worm-stage configuration. This reduces heat generation and allows higher input power at similar output ratios.

Q: How is lubrication managed across two stages?

A: The PC071 helical stage uses a separate oil compartment (CKC150 / ISO VG32). The PMRV090 worm stage uses ISO VG320. Each compartment has dedicated fill/drain plugs and must be serviced independently.

Q: Can additional ratios be achieved beyond the catalogue range?

A: Yes | contact our engineering team for ratio combinations outside the standard catalogue. Different PC input ratio variants enable custom combinations.

Q: What motor sizes are compatible?

A: The PC071 pre-stage accepts motor frames from 63B5 (PC063) to 90B5 (PC090). Refer to the PC-PMRV combinations table and motor mounting dimensions for exact compatibility.

Q: Is the output shaft the same as a standalone PMRV?

A: Yes. Output shaft dimensions of PC071+PMRV090 are identical to the standalone PMRV090, ensuring full compatibility with existing couplings, sprockets, and pulleys.

🇩🇪 Germany

Application: Automotive assembly conveyor systems

The PMRV series arrived precisely to spec. The aluminium die-cast housing is impressively rigid, and after 18 months of 3-shift operation we have had zero failures. Our procurement team now uses this supplier exclusively.

🇺🇸 United States

Application: Food-grade packaging line drives

Synthetic oil fill and the smooth surface finish made FDA audits straightforward. The gearboxes run quietly and maintain ratio accuracy even after 10,000 operating hours.

🇮🇳 India

Application: Textile spinning frame drives

We replaced three competitor brands with PMRV063 units and saw maintenance calls drop by over 60%. The torque arms for hollow-bore units were also well-engineered and simple to fit.

🇮🇹 Italy

Application: Bottling machine conveyor drives

IEC flanges aligned perfectly with our Siemens motor range. The broad ratio selection meant we could standardise on one gearbox family across our entire machine lineup | a huge inventory simplification.

🇧🇷 Brazil

Application: Agricultural irrigation pump drives

Despite harsh outdoor conditions | high humidity, dust, UV | the sealed aluminium housing and quality seals kept lubricant in and contamination out. Highly recommended for outdoor industrial duty.

🇦🇺 Australia

Application: Mining conveyor belt tensioning systems

The two-stage PMRV-PMRV units gave us the extreme reduction ratios we needed without resorting to expensive custom gearboxes. The technical support team helped with selection | very responsive.