Duty inputs
Operating and dimensional requirements
- Load direction
- Fatigue exposure
- Toughness
- Section size
Alloy steel · Bar to blank
Shafts & pins.
Steel bar stock and machined blanks for shafts, pins and rotating parts, supplied to the agreed drawing and delivery condition.
Supplied forms
Round bar / Q&T bar / Peeled bar / Shaft blanks
Send a specification View supply detailsMachined shaft form
Grade follows duty.
Select shaft and pin stock around the drawing, section size, load direction, fatigue exposure and toughness requirement.
Allow for the next cut.
Specify the starting bar diameter, finished shaft or pin dimensions, and the machining allowance needed at the next operation.
Define the release checks.
Set dimensions, mechanical tests, UT when specified and heat traceability.
Material & specification
Shaft bar grades and supply.
Match the grade and condition to the drawing.
Supply limits are confirmed with the enquiry.
Grades to review
40CrGeneral shaft & pin routes 42CrMo4 / 4140Higher-load routes; review Q&T condition 34CrNiMo6Heavy-duty, toughness-led review 35CrMoSelected strength & heat-treatment routesConfirm the required standard and properties; grade names alone do not establish interchangeability.
Supply specification
- Material form
- Hot rolled or forged bar; cut-to-length material; rough-machined or semi-finished blanks.
- Condition & surface
- Q&T, peeled or turned. Ground where relevant to the agreed route.
- Size & allowance
- Diameter, length, rough and final dimensions, straightness and machining allowance to drawing.
- Inspection
- Chemistry, mechanical properties, dimensions and surface. UT when specified.
- Documents
- MTC and heat traceability. Third-party inspection support on request.
Drawing-based components and forged routes require review. The photograph illustrates a shaft form; final machining and finishing scope must be agreed.
Turn the shaft drawing into an enquiry
State the ordered stock size, the section size at heat treatment and the final shaft or pin dimensions separately. Identify the machining allowance, remaining operations, drawing revision and agreed inspection records.
Technical notes & order checks
Typical parts
Motor, transmission, gear and drive shafts; pins, spindles and rotating mechanical parts. State the part function, load direction, rotation and fatigue exposure.
Order checklist
Include grade and standard, diameter, length, rough and final size, drawing revision, quantity, delivery condition, machining allowance, heat treatment, inspection, packing and destination.
When is Q&T or a forged route worth reviewing?
Review the route for higher loads, larger diameters, fatigue exposure, toughness needs or drawing-based mechanical properties. State the required delivery condition and inspection scope in the enquiry.
Why does machining allowance matter?
It affects starting diameter, surface preparation, cutting plans and dimensional inspection. Share rough and final dimensions when available; agree who handles heat treatment, machining, finishing and release inspection.
Which records should accompany the order?
Agree the MTC, heat number traceability, mechanical test and specified UT records, dimensional and surface inspection, packing list and any third-party inspection records.
Supply requirements
Five details to agree before ordering.
Specify the part, material, delivery condition, inspection requirements and quotation details together.
- 01ComponentShafts & pins
- 02Grade40Cr
- 03ConditionHot rolled or forged
- 04InspectionUT
- 05RFQDrawing + destination
Candidate grades
Steel grades and delivery condition
- 40CrCommon alloy route for shaft and pin requirements.
- 42CrMo4 / 4140Higher-strength alloy route for demanding sections.
- 34CrNiMo6Consider where high loads and specified toughness are key requirements.
- 35CrMoAlternative alloy route after size and duty review.
- Project-specific routeConfirm load, section and fatigue conditions.
Supply and release
Inspection and batch traceability
- Supply stages
- Hot rolled or forged · Q&T · Peeled or turned
- Inspection
- UT · Straightness and dimensions · Mechanical properties
Production handoff
Connect bar condition to the next operation.
The order should state who is responsible for heat treatment, bar preparation, machining allowance, finishing and release inspection.
- Forging route review
- Heat treatment
- Peeling or turning
- Rough machining
Source imagery
See the component context.
Material supply for shaft and rotating component production.
Semi-finished shaft blanks for machining to the final drawing.
RFQ checks
Questions buyers ask first.
Can I enquire about rough-machined shaft blanks?
Yes. Share the shaft or pin drawing, grade and standard, rough and final dimensions, machining allowance and required delivery condition. The quotation should identify which machining and heat-treatment steps are included.
Which dimensions should a shaft-bar enquiry include?
Provide the starting bar diameter and length, the rough-machined dimensions and the final drawing dimensions. State machining allowance and the section size during heat treatment so the starting stock, processing sequence and dimensional checks can be planned together.
How should inspection records identify the supplied shaft bars?
Use the heat number and agreed batch identification to link the supplied bars to their inspection documents and packing list. Specify the material certificate, mechanical results, dimensional and surface records, plus ultrasonic or third-party inspection when required by the order.
Technical references
Technical guides and specifications.
40Cr / 41Cr4 / SCr440 round bar for shaft routesReview the 40Cr grade, delivery condition, machining, and inspection route for shafts, gears, and rotating parts.34CrNiMo6 product pageReview Ni-Cr-Mo alloy steel where shaft toughness, section size, and fatigue exposure need closer discussion.Fatigue and toughness inspectionPrepare fatigue, toughness, UT, mechanical testing, and traceability wording before RFQ.Gear and spline steel bar RFQ checklistTranslate tooth and spline routing, machining allowance, heat treatment, inspection, and drawing revision into the bar RFQ.Pin, bushing, and coupling steel selectionReview load, wear, alignment, section size, surface condition, and machining route before fixing the bar grade.Crankshaft and connecting-rod bar RFQ reviewConnect fatigue-critical geometry, forging or machining route, heat treatment, inspection stage, and traceability to the stock requirement.
Component RFQLock the route before quotation.
Send the shaft or pin drawing, load and fatigue conditions, grade and standard, rough and final dimensions, delivery condition and machining allowance. Include specified inspection records, quantity and destination.
Shaft selection & technical references
Open the guide relevant to your drawing or purchasing requirement.
Choose the material
Define the blank and machining allowance
Agree inspection and delivery records
More shaft references
- 40Cr / 41Cr4 / SCr440 round bar for shaft routes
- 34CrNiMo6 product page
- Fatigue and toughness inspection
- Gear and spline steel bar RFQ checklist
- Pin, bushing, and coupling steel selection
- Crankshaft and connecting-rod bar RFQ review
- Processing routes
- Request shaft bar quote
- Mill-origin and route visibility
- Steel bar processing route checklist
- Centerless peeling vs grinding
- 40Cr vs 42CrMo
- 42CrMo4 vs 4140 vs SCM440
- Diameter tolerance RFQ wording
- Steel bar straightness requirements
- Purchase order wording checklist
- Drawing revision control checklist
Your part. Your specification.
Share the part, grade, sizes, condition, inspection scope, quantity and destination.
Discuss your project
Send your requirements directly to JOTAIN. We will reply to your email.