18CrNiMo7-6 Vaihde- ja ura-akseli

18CrNiMo7-6 Vaihde- ja ura-akseli — The 18CrNiMo7-6 Gear and Spline Shaft combines an M5 Z18 gear and an M2.5 Z28 spline on one 758 mm long shaft. The specified material is 18CrNiMo7-6, with carburizing and quenching to HRC59-63. Integrating the gear and spline on a single component makes the relationship between tooth features, bearing journals and shaft datums especially important for the production drawing and inspection plan.

Product overview

The 18CrNiMo7-6 Gear and Spline Shaft combines an M5 Z18 gear and an M2.5 Z28 spline on one 758 mm long shaft. The specified material is 18CrNiMo7-6, with carburizing and quenching to HRC59-63. Integrating the gear and spline on a single component makes the relationship between tooth features, bearing journals and shaft datums especially important for the production drawing and inspection plan.

For quotation, define the spline as part of the complete mating interface. Tooth geometry, adjacent journals, shoulders, grooves, threads and bearing seats should be dimensioned from functional datums so the finished shaft can be inspected in the same relationship in which it operates. Dimensions not listed on this page are manufactured according to the customer-approved drawing.

Technical specifications

The values below describe this product configuration. Any dimension, tolerance, rating or fit not shown should be stated on the enquiry drawing before production.

Spline geometry and mating interface

The spline cannot be selected from nominal shaft diameter alone. Confirm module or pitch system, tooth count, pressure angle, major and minor diameters, effective engagement, tooth thickness or space-width basis, end relief and the required fit with the mating member. If the connection is intended to slide axially, also state the travel, lubrication method and permissible clearance. If it is fixed, define axial location and the features that carry or react thrust.

Datum relationships matter whenever the spline works with a bearing seat, gear, seal land or locating shoulder. A tooth form may be individually within tolerance yet still produce uneven contact if the spline axis is not controlled relative to the functional journals. Put runout, position or concentricity requirements on the drawing only where they protect assembly performance, and identify the datum used for both machining and inspection.

Material, heat treatment and surface condition

18CrNiMo7-6 is specified here with carburizing and quenching to HRC59-63. Long, multi-feature shafts require heat-treatment and finishing plans that account for distortion and the relationship between several functional diameters. If case depth, core condition, tooth finishing or journal grinding are required, define those characteristics on the drawing and identify their inspection locations.

Material condition, heat treatment and finish should be reviewed as one process chain. Rough machining before heat treatment can leave stock for later finishing; thermal processing can change size or straightness; final grinding or hard finishing may be required only on features whose tolerance or surface condition demands it. State the finished requirement rather than prescribing an unnecessary process unless the process itself is part of the approved design.

Application and duty review

This integrated layout can reduce the number of separate torque-transfer components in a transmission assembly, but the exact application depends on gear geometry, spline fit, bearing support, load path and speed. Provide the assembly drawing or mating parts so gear-to-spline alignment, axial location and runout can be reviewed together.

For a new design, share the expected continuous and peak torque, speed range, duty cycle, shock or reversing load, radial or axial loads that interact with the shaft, lubrication and environmental exposure. For a replacement component, include the mating part and photographs of wear patterns. Fretting, asymmetric flank polish, pitting or looseness can indicate alignment, fit or lubrication issues that should be corrected before a replacement geometry is finalized.

Inspection and quality planning

Inspection should be tied to the characteristics that control assembly and torque transfer. Depending on the drawing, this may include functional spline gaging, analytical tooth measurement, CMM checks, measurement over pins or balls where applicable, runout inspection, surface-roughness measurement and hardness testing. The measurement method should match the tolerance definition so supplier and customer evaluate the same feature in the same way.

For heat-treated shafts, identify the hardness location and whether the requirement concerns surface hardness only or also case depth and core condition. For integrated gear-and-spline parts, plan inspection of the relationship between tooth systems and journals rather than checking each feature in isolation. First-article reports should focus on the critical drawing characteristics that demonstrate fit and functional alignment.

Customization and drawing checklist

Ever-Power can evaluate custom geometry from a controlled drawing or a dimensioned interface definition. To prepare a quotation, please include the items below that apply to your assembly:

• 2D drawing with revision level, datums and the complete spline definition
• Mating hub, sleeve, gear or yoke geometry and the required fixed or sliding fit
• Material grade, heat-treatment condition, hardness and functional surface-finish requirements
• Torque, speed, shock or reversing load, duty cycle, lubrication and operating environment
• Critical runout, concentricity, axial location and bearing or seal interface requirements
• Order quantity, prototype or first-article requirement and requested inspection documentation

For this configuration, please also confirm: Gear pressure angle; spline pressure angle; gear form; spline fit; effective lengths; bearing journals; datum and runout requirements; torque and speed; application drawing.

Compare related options in the Vaihde- ja ura-akselit range or use the spline shaft drawing checklist before submitting the RFQ.

Installation, maintenance and failure-risk checks

Before assembly, confirm that both mating members are clean, undamaged and dimensionally compatible. Do not force a spline connection that binds during engagement; investigate burrs, alignment, fit and lead before applying assembly force. Where lubrication is required, use the lubricant and service interval specified for the machine or drivetrain rather than selecting a lubricant from the shaft material alone.

During service, inspect for fretting debris, pitting, abnormal flank polish, corrosion, looseness and changes in backlash. These symptoms can originate in the shaft, the mating member, support bearings or assembly alignment. Replacing only the visibly worn part without checking the mating connection can allow the same failure mechanism to continue.

Design review notes for repeatable production

Repeatability depends on more than a nominal spline callout. Keep the drawing revision, mating component, datum scheme and agreed inspection method under configuration control. If the mating hub, bearing arrangement, heat treatment or operating duty changes, review the interface again because a shaft that fits physically may not preserve the same contact pattern, clearance or load distribution.

When several features are produced on one shaft, tolerance allocation should follow function. Bearing seats normally control rotation, shoulders control axial location, and spline or gear features transfer torque. The drawing should make those relationships visible so the manufacturing plan can use stable datums and the inspection plan can reproduce the assembly logic. This is especially important after heat treatment, when straightness or feature relationship may change and final finishing may be needed on selected surfaces.

For procurement, avoid specifying process details that do not protect a functional requirement. A supplier may choose different tooling or machine sequences while still meeting the same finished geometry. Focus the RFQ on measurable acceptance criteria: material, heat treatment, hardness, tooth geometry, fit, runout, surface finish, dimensions and required reports. This keeps quotations comparable while allowing an efficient process route.

Production drawing requirements

For production, define the complete mating interface rather than only the nominal spline size. The drawing should show the tooth system, effective engagement, total length, adjacent journals and shoulders, datum references, required runout, material condition and any functional surface finish. If the part must replace an existing shaft, identify which dimensions were measured from unworn features and provide the mating hub, sleeve, yoke or gear information when available.

Also state the operating information that affects the engineering review: transmitted torque, rotational speed, reversing or shock load, lubrication, contamination, temperature, axial movement and expected assembly method. These inputs help align the manufacturing and inspection plan with the actual connection. Critical inspection characteristics should be identified on the drawing so the same acceptance basis can be used for first articles and repeat orders.

Usein kysytyt kysymykset

These questions cover the information most often needed to turn a spline-shaft enquiry into a manufacturable and inspectable drawing.

Request a quotation

• Controlled drawing and revision
• Mating spline/interface information
• Material and heat-treatment requirement
• Operating duty and environment
• Quantity and inspection documentation

Send the drawing and application details through the enquiry form below. The technical review will focus on the mating interface, material condition, functional datums, operating duty and inspection requirements so the quotation is based on the actual component definition.