Spur Gear

Features & Benefits

• Simple, cost-effective design
  Straight-tooth cylindrical geometry is the simplest gear form, making spur gears economical to design and produce while still providing precise motion.

• High efficiency
  Spur gears have minimal sliding friction compared to some other gear types and can reach efficiencies of roughly 94–99% for typical ratios, which helps reduce energy loss and heat generation.

• Accurate, constant speed ratio
  In involute spur gear pairs, the velocity ratio remains constant as long as teeth are correctly designed and manufactured, providing predictable kinematics for gearboxes and motion systems.

• High torque capability at moderate speeds
  Spur gears can transmit significant torque for low to medium pitch-line velocities (often recommended up to around 25 m/s for standard designs), making them suitable for many industrial and machinery applications.

• Small-module precision for emerging industries
  DD Gear focuses on small-module spur gears with tight control of tooth profile, pitch, and runout according to ISO/DIN tolerances, supporting compact EV, robotics, AGV and medical devices where space and precision are critical.

• Design flexibility
  Spur gears can be made as external or internal gears, in standalone gear pairs or as part of compound trains and planetary sets, giving engineers flexibility in packaging and ratios.

Technical Specifications

Final data will be defined according to the customer’s drawing and EV duty cycle.

Applications

Spur gears are used in an extremely wide range of industries thanks to their simplicity and high efficiency:

• Industrial gearboxes & machinery – Parallel-shaft gear pairs in reducers and gearmotors for conveyors, mixers, pumps, and general automation equipment.

• Agricultural and construction equipment – Spur gear trains in power take-off drives, auxiliary gearboxes, winches and material-handling systems.

• Robotics, AGVs & automation – Small-module spur gears in actuators, indexing devices, and compact gear trains where high positioning accuracy and efficiency matter.

• Power generation & energy – Drives in small wind/hydro equipment and auxiliary systems where robust, efficient power transfer is needed.

• Medical & instrumentation – Small precision spur gears in medical devices, analytical instruments and mechatronic assemblies requiring controlled motion.

• Textile, packaging and printing machinery – Gear trains to synchronize rollers, feeds and cutting mechanisms.

Gear Manufacturing Process

Every spur gear is produced under a controlled gear manufacturing route designed for precision and durability. A typical process flow is:

1. Forging or bar cutting of shaft blanks

2. Lathe machining of shaft diameters and reference surfaces

3. Hobbing or shaping of gear teeth

4. Drilling, milling, and other CNC machining operations

5. Heat treatment (such as carburizing, quenching, tempering, nitriding)

6. Shot blasting and stress relief as required

7. Finish machining and grinding of journals and critical surfaces

8. Gear grinding (profile or worm grinding) where accuracy demands it

9. Cleaning and rust prevention treatment

10. Final inspection and packaging for shipment

Precision Gear Customization Process

To support custom spur gear projects, DD Gear follows a clear, eight-step customization process:

Step 1 – Requirement Collection
Customers provide design requirements, 2D drawings, 3D models, or physical samples, together with basic duty cycle information (torque, speed, life, installation).

Step 2 – Drawing Design & Optimization
Based on the provided drawings or samples, DD Gear prepares or optimizes detailed manufacturing drawings and shares them with the customer for confirmation.

Step 3 – Quotation
After the drawings and technical points are confirmed, we issue a precise quotation covering tooling, piece price, lead time, and quality requirements.

Step 4 – Tooling & Fixture Preparation
Once the price is confirmed, we arrange tooling and fixture production. Any tooling cost is agreed with the customer in advance and can be offset or refunded after mass orders, according to the commercial agreement.

Step 5 – First Sample Approval
After tooling and fixtures are ready, we manufacture the first sample batch—typically within about 30 days—and ship it to the customer for testing.The customer inspects and validates the samples in their gearbox or test bench and provides feedback on dimensions, performance, and any required adjustments.

Step 6 – Mass Production
When the sample is approved, we start mass production according to the agreed production plan and quality standards.

Step 7 – Finished Product Inspection
After production, we inspect hardness, dimensions, runout, tooth accuracy, and other critical characteristics to ensure full compliance with the drawing and standards.

Step 8 – Shipping Arrangement
Once inspection is passed and shipment is approved by the customer, we arrange booking, packaging, and delivery to the specified destination.

Quality Assurance & Inspection

DD Gear applies the same quality philosophy to spur gear and all precision gears:

• Quality management systems based on ISO 9001 and IATF 16949

• Process control from incoming material to final inspection, including:

  • Material certification and chemical composition checks

  • Hardness and case depth verification after heat treatment

  • Gear measurement for profile, lead, pitch, and runout

  • Surface roughness testing on gear flanks and journals

  • Dimensional inspection with calibrated gauges and CMMs

• Traceability for each batch with inspection records and reports

• Optional documentation such as PPAP/FAIR packs on request

Packaging

Usage & Installation Notes

• Ensure correct center distance and shaft alignment to maintain proper contact pattern and avoid edge loading or premature wear.

• Set backlash according to design and accuracy class; too little backlash may cause overheating, while too much increases noise and positional error.

• Use appropriate gear lubricant (oil or grease) with the recommended viscosity and additives; good lubrication is critical to achieve high efficiency and long life.

• Avoid continuous running above the designed pitch-line velocity for standard spur gears; for very high speeds or stricter NVH targets, consider helical or other gear types.

• During maintenance, inspect the flanks for pitting, scoring and wear, and watch for changes in noise or vibration as early indicators of misalignment or overload.

Company Strength – DD Gear

• Specialized in small module, high-precision gears and shafts for EVs, humanoid robots, AGVs, and intelligent automation.

• Integrated manufacturing from forging and machining to heat treatment and gear grinding.

• Quality systems aligned with automotive standards, with experience supporting OEM and Tier 1 projects.

• Engineering support covering concept feasibility, DFM reviews, and failure analysis feedback.

• Global export capability with experience serving customers in multiple countries.

Q1: What information do you need for a spur gear quotation?
We normally need 2D drawings (PDF) and ideally 3D models; gear type (external/internal), module, tooth number, face width, material and heat-treat requirements, duty cycle (torque, speed, hours), and expected annual volume.

Q2: When should I choose spur gears instead of helical gears?
Spur gears are often preferred when you need simple, cost-effective, highly efficient transmission at moderate speeds, and when noise is not extremely critical. Helical gears are better for higher speeds and lower noise, but they are more complex and create axial thrust.

Q3: Do you supply complete gearboxes or only gears?
DD Gear focuses on precision gears and shafts. We typically supply spur gears and related components; housings, bearings and complete gearboxes are assembled by our customers or their system partners.

Q4: How efficient is a spur gear stage?
Well-designed spur gear meshes can reach about 94–99% efficiency, depending on ratio, lubrication, load and speed.

Q5: Are spur gears always noisier than helical gears?
At higher speeds, spur gears usually generate more noise because of sudden tooth engagement and single-line contact, while helical gears engage gradually and run more quietly. For moderate speeds or well-enclosed systems, spur gears may still meet your NVH targets with proper design.