Servo Motor Gearbox Selection Guide: Flange Compatibility & Integration

Quick Answer: Matching a servo motor to a gearbox requires verifying four interface dimensions: bolt hole pitch circle diameter, hole diameter and distribution, shaft extension diameter, and keyway spec. Wuma Drive's WMRV, WR, WK, WF, WS, and WKM series all include a dedicated Input Square Flange Dimension Comparison Table in the product catalog —download it at wumadrive.com/download to confirm compatibility before ordering.

1. The Integration Problem: Why Servo-to-Gearbox Matching Fails

In industrial automation, servo motors and gearboxes must be mechanically mated —yet they come from different standards worlds. Most gearbox manuals only document IEC standard flanges. Servo motors, by contrast, are offered by dozens of brands each with proprietary square flange dimensions —bolt hole pitch circle, hole diameter, shaft extension, and keyway —that differ by brand and frame size.

The result: engineers must manually cross-reference motor dimension drawings against gearbox input specs for every new project. This is slow, error-prone, and a frequent cause of costly assembly rework.

The fix is structural, not workaround-based: a dimension lookup table that maps motor brand and frame size directly to verified gearbox input dimensions.

2. What Dimensions Actually Matter for Flange Compatibility

When evaluating servo motor–gearbox compatibility, four dimensions determine whether the interface will fit and transmit torque reliably:

3. Input Square Flange Dimension Comparison Table

Wuma Drive has added a comprehensive Input Square Flange Dimension Comparison Table to the product catalogs for all six gearbox series: WMRV (worm), WR (helical), WK (helical-bevel), WF (parallel shaft), WS (helical-worm), and WKM (hypoid).

Each table entry maps a specific gearbox model to the verified input interface dimensions for mainstream servo motor brands —covering bolt hole PCD, hole diameter and count, shaft extension OD, and keyway spec. No manual cross-referencing against motor drawings is required.

4. Gearbox Series Selection by Application

Choosing the right series for your servo drive application depends on output torque, shaft direction, noise tolerance, and space constraints. The table below is a quick procurement reference:

For each series, the product catalog includes the corresponding Input Square Flange Dimension Comparison Table. Download the catalog to access all dimension data for your target series.

5. Procurement Checklist: Before You Order

Use this checklist to validate servo motor–gearbox compatibility before placing an order:

If any dimension falls outside the catalog standard, contact Wuma Drive's engineering team for a custom input adapter —we support non-standard motor interfaces across all product series.

FAQ

How do I match a servo motor to a gearbox by flange type?

Identify the motor's square flange bolt hole PCD, hole diameter, shaft OD, and keyway. Cross-reference these against the gearbox Input Square Flange Dimension Comparison Table in the Wuma Drive catalog. No manual drawing comparison is needed.

Which Wuma Drive series support square flange servo motor input?

All six series —WMRV, WR, WK, WF, WS, and WKM —support square flange motor input with verified dimension tables in the official product catalog.

Why is keyway spec the most common hidden mismatch?

The shaft and bore may fit physically, but a keyway width or depth off by 0.1 mm causes fretting under cyclic load. Always verify keyway spec —width, depth, and length —not just shaft OD.

Where can I download Wuma Drive's product catalog?

The full catalog including all Input Square Flange Dimension Comparison Tables is available free at wumadrive.com/download.

Can Wuma Drive handle non-standard motor interfaces?

Yes. For interfaces outside the catalog standard, our engineering team provides custom input adapter solutions. Contact us to confirm feasibility before ordering.