INDUSTRY COMPONENT

Keyway/Spline

Keyway and spline are mechanical components used to transmit torque between shafts and rotating elements like gears, pulleys, and couplings.

Component Specifications

Definition
A keyway is a longitudinal slot machined into a shaft or hub to accommodate a key, which prevents relative rotation. A spline consists of multiple longitudinal ridges (teeth) on a shaft that mesh with grooves in a mating hub, allowing torque transmission while permitting axial movement. Both are critical for secure power transmission in mechanical systems.
Working Principle
Keyways work by inserting a metal key into machined slots on both the shaft and hub, creating a positive mechanical lock against rotation. Splines operate through interlocking teeth between shaft and hub, distributing torque across multiple contact surfaces for higher load capacity and allowing controlled axial sliding motion.
Materials
Typically made from alloy steels (AISI 4140, 4340), carbon steels (1045, 1144), or stainless steels (304, 316). Surface treatments include hardening (case hardening, induction hardening), nitriding, or plating for wear resistance.
Technical Parameters
ParameterTypical rangeNotes & selection driver
Fit ClassANSI B92.1, DIN 5480, ISO 4156
Keyway TypesSquare, rectangular, Woodruff, Gib-head
Module/Pitch0.5-10 mm
Spline TypesInvolute, straight-sided, serrated
Pressure Angle30°, 37.5°, 45°
Tolerance GradeIT5-IT9

Ranges are indicative industry figures for RFQ preparation, not a supplier commitment. Confirm every value and standard with the legal manufacturer before ordering.

Standards
ISO 4156, DIN 5480, ANSI B92.1, JIS B 1601

Parent Products

This component is used in the following industrial products

Engineering Analysis

Risks & Mitigation
  • Shear failure under overload
  • Wear and fretting corrosion
  • Improper fit causing vibration
  • Stress concentration at keyway corners
  • Misalignment during assembly
FMEA Triads
Trigger: Insufficient material strength or improper heat treatment
Failure: Shear failure of key or spline teeth under torque overload
Mitigation: Use appropriate material grades with proper hardening, conduct torque capacity calculations, implement overload protection devices
Trigger: Poor manufacturing tolerances or improper fit
Failure: Excessive backlash, vibration, and accelerated wear
Mitigation: Adhere to ISO/DIN standards for tolerances, use proper gauging during manufacturing, implement quality control checks
Trigger: Inadequate lubrication in sliding spline applications
Failure: Galling, seizing, and excessive wear of spline teeth
Mitigation: Specify proper lubricants, design lubrication channels, implement maintenance schedules for re-lubrication

Industrial Ecosystem

Compatible With

Typical Suppliers & Equivalents

Compliance & Inspection

Tolerance
ISO 286 for shaft/hole fits, ISO 4156 for spline dimensions, typical fits: H7/h6 for keyways, 5H/5h for precision splines
Test Method
Coordinate measuring machines (CMM) for dimensional verification, surface roughness testing, hardness testing, torque testing for load capacity validation

Procurement Evaluation Criteria

A practical evidence checklist for RFQ preparation and supplier evaluation.

Technical documentation
Request current drawings, revision history, and a signed specification sheet.
Manufacturing capability
Verify equipment lists, process limits, capacity, and representative production evidence.
Inspection readiness
Confirm test methods, calibrated equipment, sampling plans, and traceable reports.
Supplier transparency
Check the legal entity, factory address, ownership, certifications, and direct contacts.

CNFX does not score or rank suppliers. Buyers must verify all claims and documents with the legal manufacturer before ordering.

Manufacturers of Keyway/Spline

Manufacturer profiles associated with Keyway/Spline.

Sourcing Keyway/Spline from China?
Tell us your specification and target quantity — we will match it against manufacturer records and come back with the factories that fit.
Request manufacturers We manufacture this

Manufacturer listings support early research and capability understanding. They are not certification, ranking, or transaction guarantees.

Share this page

Related Components

Upper Tool (Punch)
Upper Tool (Punch) is the active forming component in metal plate bending machines that applies precise downward force to create bends in sheet metal.
Main Frame
The main frame is the primary structural component of a hydraulic press, providing rigidity and stability to withstand high compressive forces during metal forming operations.
Shaft Bearing
Precision component supporting rotating shafts in vibration motors to reduce friction and maintain alignment.
Seal Groove
Precision-machined groove in aluminum bearing housings designed to accommodate sealing elements for fluid containment and contamination prevention.

Frequently Asked Questions

What is the difference between keyway and spline?

Keyways use a single key for torque transmission with fixed positioning, while splines use multiple interlocking teeth that allow axial movement and distribute loads across more surface area.

When should I use splines instead of keyways?

Use splines for higher torque capacity, applications requiring axial movement (sliding connections), or when precise angular positioning is needed. Keyways are simpler and cost-effective for fixed connections with moderate loads.

What are common failure modes for keyways and splines?

Common failures include wear, fretting corrosion, shear failure of keys, tooth deformation in splines, and improper fit leading to backlash or vibration.

Data Basis

Editorial classification, named public sources where available, and source-reviewed manufacturer records. See the editorial policy.

Preliminary Technical Classification
This page supports structured research, RFQ preparation, and supplier evaluation. It does not replace buyer-led supplier qualification, standards review, or technical approval.

Request Manufacturing Insight for Keyway/Spline

Thank you. Your request has been sent. We'll respond within 1–3 business days.
Sorry, we couldn't send your message. Please try again, or email us at [email protected].
Yoke Bracket
Get QuotesChat