United Broach designs and manufactures precision involute and straight-side spline broaches for automotive, tractor, transmission, defence and heavy engineering applications, engineered to DIN 5480, SAE and fully custom drawing specifications.
Since 2005, United Broach has been manufacturing precision spline broaches from its ISO 9001:2015 certified facility in Patiala, Punjab. Our spline broaches are trusted by automotive component manufacturers, tractor OEMs, transmission specialists and heavy engineering units across India and international export markets.
A spline broach is one of the most critical tools in any drivetrain or power-transmission manufacturing line. It is a long, multi-toothed cutting tool that progressively removes material in a single linear pass to generate the internal or external spline profile on a shaft, hub, gear or coupling. Because splines are responsible for transmitting torque between rotating components, the accuracy of the broach directly determines the strength, noise behaviour and service life of the finished assembly.
United Broach manufactures both internal spline broaches and external spline broaches, covering involute spline forms to DIN 5480, straight-side spline forms to SAE and ANSI B92.1, and fully custom profiles built from customer drawings, CAD models or physical samples.
Every broach is manufactured on CNC grinding equipment with in-process and final inspection using profile projectors, gear tooth verniers and precision height gauges, ensuring that tooth form, pitch, lead and surface finish remain within the tightest tolerances demanded by automotive and aerospace-grade specifications.
A spline broach consists of a series of cutting teeth arranged along the length of the tool body, with each successive tooth slightly larger than the one before it. As the broach is pulled or pushed through (or over) the workpiece, each tooth removes a small, controlled amount of material until the final tooth — the sizing tooth — produces the finished spline profile to the exact required dimensions. This progressive cutting action is what allows broaching to achieve far tighter tolerances and far better surface finish than milling or shaping in a single operation.
Spline broaches are typically manufactured from high speed steel (HSS) grades such as M2 and ASP, or from solid carbide for high-volume, abrasive-material production. The choice of material, coating and geometry is determined by the workpiece material, production volume, expected tool life and the specific industry application — automotive components, for instance, demand extremely high-volume tool life with consistent tooth form across tens of thousands of cycles, while defence and aerospace components prioritise dimensional certainty over raw production speed.
Internal spline broaches generate the spline profile inside a bore — for example, inside a gear hub, clutch plate, universal joint yoke or transmission coupling. The broach is pulled through a pre-drilled hole in the workpiece, with each tooth progressively cutting deeper until the bore carries the full internal spline form. Fixture design, pull-force calculation and chip evacuation are critical considerations in internal spline broach design, since the cutting action happens in a confined space with limited visibility and cooling access.
External spline broaches, by contrast, cut the spline profile onto the outer surface of a shaft. These are commonly used on pull-type or push-type broaching machines and are particularly common in tractor PTO shaft manufacturing, steering shaft production and various transmission input/output shaft applications. External broaching tools require precise alignment and rigid workholding to prevent deflection across the length of the cut, particularly on longer shafts.
United Broach manufactures spline broaches to the full range of standards used across global automotive, tractor, defence and aerospace supply chains:
Every spline broach manufactured at United Broach passes through a structured production sequence: raw material selection and heat treatment verification, rough profile grinding, CNC tooth-form grinding, relief and clearance angle generation, heat treatment (hardening and tempering) where required by tool steel grade, finish grinding, and final dimensional inspection. PVD coatings such as TiN and TiAlN are applied where specified to improve wear resistance and extend service life in high-volume production environments.
Our inspection process uses optical profile projectors, gear tooth measuring instruments and coordinate measuring equipment to verify tooth profile, pitch diameter, lead accuracy and surface finish against the approved drawing before any broach is dispatched. This is the same quality discipline that has allowed United Broach to maintain ISO 9001:2015 certification and supply tooling into export markets with strict incoming-inspection requirements.
In any torque-transmitting assembly, the spline connection is a load path. If tooth form, pitch or lead are out of tolerance, the result can be uneven load distribution across the spline teeth, premature wear, backlash, noise (particularly in transmission and steering applications), and in severe cases, fatigue failure of the mating components. This is why automotive and tractor OEMs specify tight tolerance bands on spline broaches and require supplier qualification before approving a tooling source — a process United Broach has successfully completed with numerous domestic and international customers.
Indicative manufacturing range for spline broaches produced at United Broach. Exact specification is finalised against customer drawing.
| Parameter | Specification Range |
|---|---|
| Spline Type | Internal & External, Involute & Straight-Side |
| Standards Supported | DIN 5480, SAE, ANSI B92.1, Custom Drawing-Based |
| Module Range | 0.5 to 6 module (custom ranges on request) |
| Broach Length | Up to 2000 mm (application dependent) |
| Tool Material | HSS (M2, ASP grades), Solid Carbide |
| Coating Options | Uncoated, TiN, TiAlN (PVD) |
| Tolerance Class | As per drawing / AGMA & DIN tolerance grades |
| Surface Finish | Ra 0.4 µm and finer on cutting profile |
| Pull/Push Type | Both configurations manufactured |
| Reconditioning | Available — see Broach Reconditioning Services |
Spline broaches manufactured by United Broach are deployed across critical torque-transmission components.
Internal spline broaching of gear hubs and synchroniser components for manual and automatic transmissions.
External spline generation on steering input and output shafts requiring precise torque transfer.
Straight-side spline broaching for tractor power take-off shafts to SAE specifications.
High-precision spline broaching for military vehicle transmission and drive system assemblies.
Close-tolerance internal splines for aerospace actuator and coupling assemblies.
Custom spline profiles for industrial gearbox couplings and rotating machinery.
Spline broaching solutions trusted across critical manufacturing sectors.
Two decades of precision spline broach manufacturing, backed by ISO certification and export-grade quality systems.
Quality management systems audited and certified to international standards.
Drawing, CAD and reverse-engineered spline profiles manufactured to exact specification.
Profile projector and gear tooth vernier verification on every batch before dispatch.
Tooling supplied to international customers under strict incoming inspection norms.
Structured production planning for consistent, on-time delivery schedules.
Full reconditioning and re-sharpening service to extend broach service life.
A closer look at the tooling and finished spline profiles coming off our production line.
PVD-coated cutters ready for high-volume spline and gear production.
Precision-ground external spline teeth ready for shaft manufacturing applications.
Close-up view of a finished, coated spline broach tooth profile.
Common questions about our spline broach manufacturing capability.
A spline broach is a precision multi-tooth cutting tool used to generate internal or external splines on shafts, hubs and gears. It produces the mating spline profile in a single linear cutting pass, giving accurate tooth form, pitch and surface finish for torque-transmitting components in automotive, tractor and transmission assemblies.
United Broach manufactures spline broaches to DIN 5480 involute spline standards, SAE straight-side spline standards, ANSI B92.1, and fully custom drawing-based spline profiles supplied by the customer, including non-standard pressure angles and module sizes.
Our spline broaches are manufactured from HSS (High Speed Steel) grades such as M2 and ASP and from solid carbide for high-volume and abrasive-material applications, depending on the production volume, workpiece material and tool life requirement of the customer.
Yes. We design and manufacture fully custom spline broaches based on customer drawings, sample components, or 2D/3D CAD files, including reverse-engineered profiles for replacement and obsolete tooling.
An internal spline broach cuts splines inside a bore, such as in a gear hub or coupling, by being pulled or pushed through the hole. An external spline broach generates splines on the outer surface of a shaft. Both require precise tooth geometry, but tool design, holding fixtures and relief angles differ significantly between the two.
Yes. We offer PVD coatings such as TiN and TiAlN on spline broaches to enhance wear resistance, reduce friction and extend tool life, particularly for high-volume automotive and tractor production runs.
Our spline broaches are used across automotive transmission and steering systems, tractor PTO shafts and gearboxes, defence vehicle drivetrains, aerospace actuation components, and heavy engineering equipment requiring precision torque-transmitting spline connections.
Lead time depends on broach length, profile complexity and current production load, but typical custom spline broach orders are completed within a few weeks of drawing approval. Contact our technical team with your specification for an accurate delivery timeline.
Share your drawing or sample component and our technical team will respond with a manufacturing quote.
Send us your spline broach requirement for a technical evaluation and quotation.