Power Transmission Components

Shaft Collars

Precision clamp-type shaft collars in aluminium alloy — from 6 mm to 60 mm bore. Zero shaft damage, field-adjustable, and available with optional keyway for simultaneous axial and rotational locking.

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A shaft collar is one of the most fundamental positioning components in any rotating machine. Fitted to a shaft and secured by a clamping screw, it creates a precise axial stop that holds bearings, sprockets, cams, and coupling hubs at defined positions along the shaft — without threading, welding, or machining the shaft itself.

The GBC SCS series uses a split-clamp design: a single longitudinal slot allows the collar bore to flex radially as the clamping screw is tightened, distributing clamping force uniformly around the full shaft circumference. This eliminates the stress concentration and surface indentation associated with set-screw collars, preserving shaft surface integrity across repeated repositioning cycles.

All collars in the SCS range are machined from aluminium alloy, delivering the strength-to-weight ratio required for dynamic drive assemblies while keeping rotational inertia additions below the threshold that affects system performance. Keyway options follow DIN 6885 Form A for each bore size, enabling the collar to function simultaneously as an axial locator and a full-torque rotational coupling element.

MOQ is 100 pcs per model. Custom bore tolerances, extended face widths, anodized finishes, and steel variants are available — supply your engineering drawing via the GBC enquiry page for a fast quotation.

Series Specifications

Bore range 6 mm – 60 mm
Collar type Split clamp
Material Aluminium alloy
Keyway standard DIN 6885 Form A
Clamping screws M4 / M5 / M6 / M8 / M10
Shaft fit ISO 286 h6
Surface Natural / hard-anodize
MOQ 100 pcs

Browse by Bore Size Group

Select the bore group that matches your shaft diameter. Each size range shares a common OD and clamping screw size, making cross-specification straightforward.

Small bore aluminum clamp shaft collar 6mm to 13mm bore precision instruments

Small Bore — 6 mm to 13 mm

Ultra-compact collars for precision instruments, miniature robotics, CNC accessories, and 3D printer drive shafts. M4 clamping screw. OD range 20–30 mm. Keyway available from 10 mm bore upward (3–4 mm width).

Products in this group
Medium bore aluminum clamp shaft collar 14mm to 20mm for conveyors and servo motors

Standard Bore — 14 mm to 20 mm

The most widely specified bore range, covering IEC servo motor shafts, SFU ball-screw journals, belt conveyor rollers, and printing press ink-train shafts. M5 clamping screw. OD range 35–40 mm. Keyway 5–6 mm.

Products in this group
Medium heavy bore aluminum clamp shaft collar 22mm to 35mm for gearboxes and agricultural machinery

Medium-Heavy Bore — 22 mm to 35 mm

Industrial-grade collars for helical gearbox outputs, agricultural baler drives, heavy belt conveyors, and mining auxiliary shafts. M5 to M6 clamping screw. OD range 45–60 mm. Face width 12–15 mm. Keyway 6–10 mm.

Products in this group
Large bore heavy duty aluminum clamp shaft collar 40mm to 60mm for heavy industrial machinery

Large Bore — 40 mm to 60 mm

Heavy-industrial collars for large gearbox outputs, rotary table drives, ship auxiliary machinery, rolling mill shafts, and rotary kiln drives. M8 to M10 clamping screw up to 35 N·m. OD range 70–95 mm. Face width 18–22 mm. Keyway 12–18 mm.

Products in this group

Why Choose a Clamp-Type Shaft Collar

The split-clamp design offers measurable engineering advantages over set-screw and welded alternatives across a wide range of shaft diameters and duty types.

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No Shaft Surface Damage

Clamping force is distributed uniformly around the full shaft circumference. Set-screw indentation, fretting corrosion, and fatigue-initiating stress concentrations are eliminated, preserving ground and hard-chrome shaft surfaces for the full equipment service life.

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Field-Adjustable Position

Axial position can be changed during commissioning or maintenance using only a hex key — no shaft removal, no bearing housing disassembly, no re-machining. This flexibility is particularly valuable when bearing pre-load or component lateral position must be optimised after initial assembly.

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Dual Axial-Location Modes

A single collar acts as a positive end-stop against a bearing or housing shoulder. A pair of collars sandwiches any shaft-mounted component at a freely adjustable position — effectively replacing machined shaft shoulders without the associated lead time and cost.

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Optional Keyway for Torque Locking

All SCS collars from 10 mm bore upward are available with a DIN 6885 Form A keyway, enabling the collar to transmit rotational torque simultaneously with axial positioning. One component replaces two — reducing part count, assembly time, and the risk of positional errors between separate locking and locating elements.

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Lightweight Aluminium Construction

Aluminium alloy keeps collar mass well below equivalent steel or cast iron designs, minimising the rotational inertia added to dynamic drive assemblies. At bore sizes below 30 mm, the collar mass contribution to total shaft inertia is typically below 0.5%.

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Custom Specifications Available

GBC supplies hard-anodized (25 um), electroless nickel-plated, and 316L stainless steel variants for corrosive, marine, and food-grade environments. Twin-screw configurations, extended face widths, and reduced-OD profiles are available. Provide your engineering drawing for a tailored quotation.

Application-Based Selection Guide

Match your application type and shaft diameter to the recommended GBC SCS collar model using the table below.

Application Type Typical Shaft Diameter Recommended Model Key Specification
Precision instrument / optical stage 6–8 mm SCS06 / SCS08 OD 20–30 mm, M4, ultra-compact
CNC router / 3D printer extruder 10 mm SCS10 OD 30 mm, M4, 3 mm keyway option
Ball screw fixed-end support (SFU1605) 16 mm SCS16 OD 35 mm, M5, 5 mm keyway
IEC 90-frame motor output / SFU2005 20 mm SCS20 OD 40 mm, M5, 6 mm keyway
Helical gearbox output / conveyor pulley 25 mm SCS25 OD 45 mm, M5, 8 mm keyway
Agricultural baler / heavy belt conveyor 30 mm SCS30 OD 55 mm, M6, 8 mm keyway
Large gearbox output / rotary table drive 40 mm SCS40 OD 70 mm, M8, 12 mm keyway
Ship auxiliary / large industrial fan hub 45 mm SCS45 OD 80 mm, M10, 14 mm keyway
Large pump / rolling mill roller shaft 50 mm SCS50 OD 85 mm, M10, 3 mm wide slot
Crusher / rotary kiln gearbox output 60 mm SCS60 OD 95 mm, M10, 18 mm keyway

Installation Overview

All GBC SCS clamp shaft collars install with a single hex key in four steps. No adhesive, no shaft modification, and no special tooling required for bore sizes up to 35 mm.

01

Verify Shaft Diameter

Confirm the shaft diameter falls within ISO 286 h6 tolerance using a calibrated micrometer. Degrease the clamping zone and remove burrs.

02

Slide and Position

Slide the collar onto the shaft to the required axial location. Use a depth gauge or spacer as a reference for repeatable placement.

03

Tighten Progressively

Tighten the clamping screw in three incremental steps — 30%, 70%, then full rated torque — checking position after each step. Apply threadlocker for vibration environments.

04

Verify Under Load

Apply the expected axial service load and confirm zero collar movement. Re-check torque after the first full operating shift for vibrating or cyclic-load applications.

Detailed installation torque values and shaft tolerance specifications are listed on each individual product page. For assemblies with bore sizes above 40 mm, a calibrated torque wrench with a hex-bit socket is mandatory — hand-held T-bar keys cannot reliably achieve the rated M8 and M10 clamping torques required at these bore sizes.

Frequently Asked Questions

Common technical and ordering questions about GBC SCS series shaft collars.

What is the difference between a clamp-type and a set-screw shaft collar?
A set-screw collar uses one or two radial screws that bear against the shaft surface at a single point, creating a localised stress concentration that indents the shaft and initiates fretting corrosion. A clamp-type collar uses a longitudinal slot and a single clamping screw to close the bore uniformly around the full shaft circumference, distributing clamping force over a 300-degree-plus contact arc. This eliminates shaft surface damage, allows repositioning without shaft refurbishment, and provides more consistent retention force under vibrating and cyclic-load conditions.
How do I select the correct bore size if my shaft is at the boundary between two models?
Measure the shaft with a calibrated micrometer and compare the result to the h6 tolerance band of the candidate collar. For example, a shaft measuring 13.2 mm is outside the h6 range for SCS13 (13.000–12.989 mm) and should use the SCS14 (14.000–13.989 mm) with a thin shim, or the shaft should be re-ground to 13 mm h6. Never force an undersized collar — distorting the bore reduces holding force and risks cracking the collar body.
Do all SCS collars include a keyway as standard?
No. All GBC SCS collars are supplied as plain bore (no keyway) as the default. The keyway is an option that must be specified at the time of order. Keyway dimensions follow DIN 6885 Form A for each bore size. For SCS06 and SCS08, no keyway option is available due to insufficient wall thickness at these bore sizes. From SCS10 upward, the keyway option is available and must be indicated on your purchase order or engineering drawing.
What shaft surface finish and tolerance is required for reliable clamping?
Specify the mating shaft to ISO 286 h6 tolerance for optimal performance. The h6 tolerance provides a sliding fit before clamping (zero interference) and maximises the radial clamping pressure once the screw is tightened. Surface roughness should be Ra 0.8–1.6 um (ground or finely turned finish). A rough or out-of-round shaft reduces the effective clamping contact area and can reduce axial holding force by 20–30% compared to a correctly toleranced surface.
Can GBC supply shaft collars in stainless steel or with food-grade surface treatment?
Yes. GBC supplies 303 and 316L stainless steel variants of any SCS model on request. For food-contact and pharmaceutical applications where aluminium is acceptable, a hard-anodized finish (25 um) with an A2 stainless clamping screw provides adequate corrosion resistance for indirect-contact environments. For direct wash-down duty with aggressive detergents, 316L stainless with electropolish is the recommended specification. Contact GBC via the enquiry page with your application details and required quantity.
What is the minimum order quantity, and are custom dimensions available?
The standard MOQ is 100 pcs per model per order. Custom specifications — including non-standard bore diameters, extended or reduced face widths, alternative OD profiles, twin-screw configurations, and special surface treatments — are available from GBC with a minimum order of 100 pcs. Submit a detailed engineering drawing with your enquiry for an accurate quotation and lead-time estimate. The product catalogue dimensions are provided for reference only; GBC manufactures to the customer's drawing.

Ready to Specify Your Shaft Collar?

Browse individual model pages for full dimensional data and application guidance, or contact GBC with your engineering drawing for a custom quotation. MOQ 100 pcs. Fast turnaround on standard aluminium SCS series.

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