描述
Telescopic / Sliding
Splined Shafts
Engineered for axial sliding while transmitting torque — driving PTO shafts, suspension articulation, telescopic steering columns and adaptive driveline geometry across Australia’s agricultural, automotive and heavy-vehicle sectors.
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Few driveline components solve as many design problems at once as the telescopic splined shaft. By engaging an external (male) splined member with a matched internal (female) sleeve, the assembly transmits full rated torque while still permitting axial extension or retraction — accommodating thermal growth, suspension travel, articulation between tractor and implement, or service-friendly disassembly without disturbing surrounding components.
Ever-power has produced telescopic and sliding splined shaft assemblies for the Australian market for over 22 years, supporting agricultural OEMs across the Riverina, automotive driveshaft rebuilders in Adelaide, and heavy-vehicle manufacturers in Brisbane and Perth. Custom envelope, custom stroke, custom torque rating — drawn, built and inspected to your specification.
Where Telescopic Splines Earn Their Keep
Length Variation Without DecouplingWhen the angular alignment between two driven components varies during operation — tractor drawbar pivot, semi-trailer fifth wheel, IFS suspension travel — a telescopic spline absorbs the length change without breaking the torque path. |
Service & Assembly ConvenienceCompressing the telescopic section allows the shaft to be fitted between two pre-installed flanges, eliminating the need to disturb engines, gearboxes or final drives during installation or replacement. |
Tolerance & Stack-Up AbsorptionManufacturing variation in chassis length, gearbox mounting position and axle location accumulates to ±10 mm or more — easily absorbed by a sliding spline while a fixed-length shaft would bind or pre-load the bearings. |
Vibration & Thermal ManagementHardened spline interfaces under controlled clearance damp resonance and accommodate thermal expansion of long shaft runs — a 3-metre steel driveshaft grows roughly 1.4 mm per 40 °C temperature swing. |
Specification Range
| Parameter | Standard Range | Notes |
|---|---|---|
| Spline Profile | Involute / parallel-side / triangular | DIN 5480 / DIN 5463 / SAE J498 — drawing-driven |
| Outer Diameter | Ø20 mm – Ø180 mm | Larger sizes available on enquiry |
| Collapsed Length | 300 mm – 2400 mm | Customer-specified per chassis envelope |
| Stroke / Plunge | 50 mm – 600 mm | Sized to allowed length variation plus 25% margin |
| Material | 42CrMo4 / 4140 / 20MnCr5 | Through-hardened or case-carburised |
| Spline Hardness | 52 – 58 HRC (induction) | Case carburised 58 – 62 HRC, 0.8 – 1.5 mm CHD |
| Sliding Coating | PTFE / phosphate / nylon | Reduces sliding friction by up to 70% under load |
| Backlash | 0.05 – 0.20 mm circumferential | Tighter classes available with selective fit |
| Torque Rating | Up to 18,000 N·m | Dependent on diameter, profile and material spec |
| Sealing | Nitrile / Viton boot or wiper seal | IP65 dust and water resistance achievable |
Manufacturing Workflow
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01
Forging & NormalisingBar stock cut to length and upset-forged where stepped diameters reduce machining waste. Normalising at 870 °C produces uniform pearlite-ferrite grain structure prior to spline cutting. |
02
Spline Hobbing or RollingExternal splines hobbed on Liebherr or Mitsubishi machines for short runs, cold-rolled on two-die rotary mills for high-volume automotive batches — gaining 30% fatigue improvement. |
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03
Female Spline BroachingInternal sleeve splines broached on horizontal machines, achieving DIN 5480 quality 8h or 9h fit class. Push-broaching for short engagement, pull-broaching for through-bored sleeves. |
04
Induction HardeningSpline flanks selectively induction-hardened to 52–58 HRC to a controlled depth of 2.0–3.5 mm, leaving the core tough at 28–32 HRC for impact resistance. |
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05
Friction CoatingPTFE-impregnated nylon coating sprayed and cured on female spline ID, or manganese phosphate dip on male flanks — selected against duty-cycle, sliding speed and ambient contamination. |
06
Functional Test & PackEach assembly tested for sliding torque (typically < 25 N·m at 50 N·m transmitted load), static breakaway, and rotational backlash before VCI bagging and crating. |
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Application Domains
Agricultural PTO DrivesStandard 540 / 1000 RPM tractor PTO shafts for balers, harvesters, slurry tankers and rotary cutters. Lemon, triangular and 6-spline interfaces per ISO 500 and ASABE standards. |
Heavy Vehicle DriveshaftsSlip-yoke driveshafts for 4×4, 6×6 and 8×8 trucks — accommodating up to ±100 mm suspension articulation while transmitting up to 12,000 N·m peak torque to differential. |
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Construction EquipmentArticulated dump trucks, motor graders, telehandlers and concrete pump trucks — telescoping driveshafts compensate for chassis pivot motion and fully loaded ride-height changes. |
Steering ColumnsTilt-and-telescope automotive steering columns absorb crash energy through controlled spline collapse — qualified to ECE R12 and ANCAP frontal-impact protocols. |
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Mining EquipmentContinuous miners, longwall shearers and load-haul-dump units — rugged telescoping shafts survive Pilbara and Hunter Valley duty cycles with case-carburised splines. |
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Industrial DriveshaftsConveyor drives, pump shafts, marine propulsion and cooling-tower fan drives — bridging misaligned bearings without imposing parasitic axial loads. |
Why Choose Ever-power
→ Single-Source CapabilityForge bar, hob splines, broach female sleeves, induction harden, coat and assemble — every step under one quality system, eliminating finger-pointing between sub-suppliers. |
→ 22 Years, 38 CountriesEstablished 2003. Over 1.6 million spline assemblies shipped, including more than 280,000 telescopic units to agricultural, automotive and heavy-vehicle clients worldwide. |
→ IATF 16949 & ISO 9001 CertifiedAutomotive-grade quality system, EN 10204 3.1 mill test certificate, dimensional CMM report, hardness curve and PPAP/FAIR available on request — full traceability to heat number. |
→ Defect Rate < 250 PPMThree-year rolling average across telescopic shaft production. Each assembly is functionally tested for sliding torque, breakaway and backlash before packaging. |
→ Australian Logistics SupportChAFTA Form for duty exemption issued with every shipment. FCL and LCL ocean freight to Sydney, Melbourne, Brisbane, Adelaide and Fremantle. DDP option available. |
→ Standard Lead Time 25–35 DaysProduction windows reserved monthly for repeat customers. Expedited 18-day production available for line-down emergencies subject to capacity. |
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Australian Project Case Studies
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Riverina, NSW · Agricultural Implements
Round Baler PTO Shafts — 1,200 UnitsA Riverina agricultural implement manufacturer building large-square balers for export to South-East Asia approached Ever-power after their existing supplier struggled with PTO shaft delivery and field-failure complaints. The specification called for ASABE Category 6 1-3/4 inch 20-spline interface, 540 RPM continuous, 1,800 N·m peak torque, with 350 mm telescopic stroke. Ever-power supplied 1,200 units across the 2025 production season — 42CrMo4 induction hardened, manganese phosphate coated, fitted with overload friction clutch interface. Field returns dropped to under 0.3% within the first 12 months. Outcome: Field failure rate cut by 80%, supplier relationship continued into 2026 model year.
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Adelaide, SA · Heavy Vehicle Driveline
Mining Truck Slip-Yoke DriveshaftsAn Adelaide-based heavy-vehicle driveshaft remanufacturer servicing mining fleets across South Australia and the Northern Territory specified Ø75 mm 16-tooth involute slip yokes with 200 mm stroke and 12,000 N·m torque rating, suitable for 80-tonne haul truck operation in 50 °C ambient conditions. Ever-power case-carburised the male splines to 60 HRC at 1.2 mm CHD, broached the matching female yoke to ISO 8h and supplied 480 paired sets over 18 months, with full PPAP documentation and individual-serial traceability. Outcome: Mean time between failures lifted from 4,800 to 7,200 operating hours.
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Frequently Asked Questions
How do I size the telescopic stroke for my application?Calculate the maximum length variation between the two driven flanges through the full operating envelope (suspension travel, articulation angle, thermal growth) and add 25% as a safety margin. Provide both collapsed and extended length on the drawing — we confirm spline engagement length remains adequate at maximum extension. |
What sliding torque can I expect under load?A typical Ø50 mm involute spline transmitting 500 N·m torque shows 15–35 N·m axial sliding force depending on coating and lubrication. PTFE-impregnated nylon coating reduces sliding force by approximately 60–70% versus uncoated steel-on-steel and is recommended whenever the shaft slides under load. |
Can you supply telescopic shafts to ISO 500 PTO standards?Yes. We routinely supply ISO 500 Type 1 (1-3/8 inch 6-spline), Type 2 (1-3/8 inch 21-spline), Type 3 (1-3/4 inch 20-spline) and the 8-spline metric variants. Overload clutch interfaces, shear-bolt, ratchet and friction-disc options are available. |
What sealing options prevent contamination ingress?Convoluted nitrile or Viton boots provide IP54 protection for indoor industrial use. For outdoor and off-highway applications a wiper seal at the sleeve mouth combined with a vented end-cap reaches IP65. Lubricated for life with NLGI 2 EP grease unless specified otherwise. |
Do you balance assembled telescopic shafts?Yes. Driveshaft assemblies operating above 2,500 RPM are dynamically two-plane balanced to ISO 1940 G6.3 or G2.5 grade depending on application. Balance certificates issued per individual serial number for automotive and heavy-vehicle use. |
What is the typical lead time and minimum order quantity?Standard production lead time is 25–35 working days from drawing approval. MOQ is 50 units for catalogue sizes, 200 units for fully custom designs. Expedited 18-day production available subject to material availability and capacity confirmation. |
Can you reverse-engineer existing telescopic shafts?Yes. Send a sample to our Australian sales contact and we will measure spline geometry, hardness profile, surface coating and overall envelope dimensions, then issue a manufacturing drawing for your approval before tooling. Typical reverse-engineering cycle is 10–14 working days. |
Send Us Your Drawing or Sample
Our engineering team responds to every Australian enquiry within one business day. Quotations include budgetary pricing, indicative lead time, recommended material grade and DFM feedback before you commit to tooling.
Browse the complete spline shaft catalogue from the Ever-power home page.
