United Broach manufactures precision keyway broaches for shafts, hubs, gears, pulleys and couplings, engineered for accurate slot width, depth and positional accuracy across automotive, tractor and heavy engineering applications.
United Broach has been manufacturing precision keyway broaches from its ISO 9001:2015 certified Patiala facility since 2005, supplying automotive, tractor, electrical motor and heavy engineering manufacturers across India and export markets.
A keyway broach is a single or multi-pass linear cutting tool used to machine a straight rectangular slot — the keyway — inside a bore. This slot allows a key to be fitted between a shaft and a mating hub, gear, pulley or coupling, locking the two components together so they rotate as a single unit and transmit torque without relative slip.
Unlike spline broaches, which generate a complex multi-tooth profile, keyway broaches cut a single, simple slot — but the precision required is just as demanding. Keyway width, depth, parallelism and position relative to the bore axis must all stay within tight tolerance to ensure correct key fit, even load distribution and long-term assembly reliability.
Keyway broaching is typically performed using a vertical or horizontal broaching press. The workpiece — a gear, hub, pulley or coupling with a pre-machined bore — is mounted over a guide bushing that matches the bore diameter precisely. The keyway broach is then pushed or pulled through a slot in the bushing and through the bore in a single linear stroke (or multiple passes for deeper or harder-material keyways), progressively cutting the keyway to its finished width and depth.
The guide bushing plays a critical role: it keeps the broach centred and prevents it from drifting sideways during the cut, which would otherwise produce a keyway that is off-position relative to the bore centreline. United Broach manufactures matched broach-and-bushing sets, ensuring the customer receives a complete, ready-to-use keyway broaching system rather than a standalone tool that still needs fixture engineering on the customer's end.
Several factors influence keyway broach design and material selection:
Every keyway broach manufactured at United Broach is produced using CNC grinding equipment, with roughing and finishing teeth ground to precise progressive step heights along the tool body. After heat treatment and finish grinding, each broach is inspected for width, depth, straightness and surface finish using optical comparators, height gauges and surface roughness testers before dispatch.
For customers requiring a complete broaching system, we also manufacture the matched guide bushing to the exact bore tolerance specified, eliminating fitment issues on the shop floor and ensuring the keyway is cut accurately on the first production run.
Keyway broaches manufactured by United Broach are widely used across torque-transmission assemblies where a shaft must be positively locked to a rotating component. This includes gear hubs in automotive and tractor transmissions, pulleys and sprockets in industrial power transmission systems, couplings in pump and motor assemblies, and various custom components across heavy engineering and defence manufacturing where a keyed shaft-hub connection is specified on the engineering drawing.
An inaccurate or misaligned keyway can cause uneven load distribution on the key, leading to premature wear, key shear, looseness in the assembly and, in rotating machinery, vibration and noise. For automotive and tractor manufacturers running high-volume production lines, keyway broach accuracy directly affects assembly line yield — a broach producing slightly oversized or undersized keyways can cause downstream rejection of finished components. This is why United Broach maintains strict in-process and final inspection on every keyway broach leaving our facility.
Indicative manufacturing range for keyway broaches. Final specification confirmed against customer drawing.
| Parameter | Specification Range |
|---|---|
| Keyway Width | 2 mm to 50 mm (custom sizes on request) |
| Keyway Depth | As per drawing / standard keyway tables |
| Bore Diameter Range | Up to 250 mm (application dependent) |
| Tool Material | HSS, Carbide-Tipped, Solid Carbide |
| Coating Options | Uncoated, TiN, TiAlN (PVD) |
| Guide Bushing | Manufactured as matched set on request |
| Tolerance Class | As per drawing / standard keyway tolerance grades |
| Surface Finish | Ra 0.4 µm and finer on cutting faces |
| Reconditioning | Available — see Broach Reconditioning Services |
Keyway broaches manufactured by United Broach support critical shaft-hub locking assemblies.
Internal keyway broaching for transmission and gearbox gear hubs.
Keyway broaching for tractor pulleys, sprockets and PTO components.
Precision keyways for motor and pump shaft-coupling assemblies.
Keyway broaching for flexible and rigid shaft couplings in industrial machinery.
Keyway features in automotive driveline and accessory drive components.
Custom keyway broaching for defence vehicle and equipment assemblies.
Keyway broaching solutions across critical manufacturing sectors.
Two decades of precision keyway broach manufacturing experience, backed by ISO certification.
Audited quality management systems across our full manufacturing process.
Complete broaching systems engineered for accurate, repeatable cuts.
Dimensional verification on every batch before dispatch.
Supplying international customers under strict incoming inspection norms.
Structured production planning for consistent delivery.
Full re-sharpening service to extend keyway broach service life.
A closer look at segment broaches and tooling used in keyway and slot manufacturing.
Multi-piece broach sets engineered for keyway and internal profile manufacturing.
Rack and segment broaches manufactured in batches for consistent quality.
Consistent tooth form across every broach ensures repeatable keyway accuracy.
Common questions about our keyway broach manufacturing capability.
A keyway broach is a precision cutting tool used to machine a straight, rectangular slot called a keyway inside a bore. The keyway allows a key to be inserted to lock a shaft and hub together so they rotate as one assembly, transmitting torque without slipping.
We manufacture keyway broaches across a wide range of keyway widths and depths to suit standard metric and imperial keyway dimensions, as well as fully custom keyway sizes specified by the customer drawing.
Keyway broaches are manufactured from high speed steel (HSS) grades for general-purpose applications and from solid carbide or carbide-tipped construction for high-volume or abrasive workpiece material applications requiring extended tool life.
Yes. We design and manufacture keyway broaches and the corresponding bushings for any bore diameter and keyway dimension supplied on a customer drawing, including replacement tooling for legacy and obsolete part numbers.
Most keyway broaching operations use a guide bushing matched to the bore diameter to keep the broach aligned and centred during the cut, ensuring the keyway is positioned accurately relative to the bore axis. United Broach manufactures matched bushing sets along with the broach.
Keyway width and depth tolerances are typically held within a few hundredths of a millimetre, depending on the broach condition, machine rigidity and bushing fit, meeting standard automotive and industrial keyway tolerance classes.
Reconditioning frequency depends on production volume, workpiece material hardness and cutting parameters, but most customers recondition keyway broaches after a defined number of cycles to restore cutting edge sharpness and dimensional accuracy. United Broach offers reconditioning services for this purpose.
Our keyway broaches are used in automotive transmission and engine component manufacturing, tractor gearbox and PTO assemblies, electric motor and pump shaft manufacturing, and general heavy engineering applications requiring shaft-hub locking features.
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