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S5M Belt 145-4360mm, 5mm 9/15/20/25mm CR, ISO 13050 Timing Belt Supplier

S5M Synchronous Belt — a 5mm pitch STS/STD modified curvilinear tooth timing belt for compact, high-speed precision drives.

S5M belts driving CNC, packaging, conveyor and printer machinery across industrial, office and appliance applications

Overview

The S5M Synchronous Belt is a metric-pitch member of the modified curvilinear tooth belt family, with a 5.00 mm tooth pitch. It transmits power through the meshing of belt teeth with pulley grooves — so there is no slip and no speed fluctuation, even under changing loads.

The rounded modified curvilinear (STS/STD) tooth profile reduces stress concentration at the tooth root, giving S5M a clear edge over trapezoidal-profile belts of the same size. The result is higher load capacity, quieter running and longer service life in compact, high-speed layouts.

S5M belts require no lubrication, produce no pollution and run with low noise. Transmission efficiency reaches 98% or more, the speed ratio extends to 1:10, and the allowed line speed reaches 40 m/s. Multi-shaft drives are fully supported.

Technical Specifications

Tooth Pitch

5.00 mm

Tooth Height

1.91 mm

Belt Thickness

3.4 mm

Max Line Speed

40 m/s

Transmission Efficiency

98% +

Speed Ratio

Up to 1:10

Operating Temperature

-30~+90 °C

Pitch Length Range

145–4,360 mm

Common widths: 9 / 15 / 20 / 25 mm, custom widths available on request.

Materials & Construction

Every S5M belt is built with a three-layer composite structure using premium, industry-grade materials for stable dimensions and a long service life.

LAYER 01 Tensile Member (Core)High-strength glass fiber cord carries the full tensile load with very low elongation, keeping pitch length stable under load.
LAYER 02 Body CompoundPremium synthetic chloroprene rubber (CR), blended with multiple additives for heat, cold, oil, water and chemical resistance.
LAYER 03 Tooth FacingSpecially treated Nylon 66 high-elastic fabric protects the tooth surface from wear, lowers friction and preserves tooth form.

Key Advantages

Zero Backlash, Exact Ratios

Positive tooth engagement eliminates slip entirely, so the speed ratio stays constant under changing loads.

Up to 98% Efficiency

More efficient than friction belts, with no energy lost to slip or creep.

High-Speed Capable

Line speeds up to 40 m/s with smooth, quiet running even at high RPM.

Maintenance-Free

No lubrication needed, no pollution, low noise and minimal upkeep.

Strong Dynamic Flex

Excellent flex-fatigue resistance and strong crack-propagation resistance under continuous cycling.

Built to Last

Outstanding ozone resistance, plus heat, aging and wear resistance for extended service life.

Broad Chemical Resistance

chloroprene rubber (CR) resists oil, water, acids and alkalis in standard construction.

Wide Operating Range

Operates from -30 to +90 °C without compromising performance.

Four Steps to the Right Belt

STEP 01 Confirm the Pitch

S5M uses a 5.00 mm pitch. Verify against your existing pulley tooth spacing.

STEP 02 Measure Pitch Length

Measure the centre distance or existing belt, then pick the matching S5M length from the selector above.

STEP 03 Pick the Width

Choose from 9/15/20/25 mm, or ask us for a custom width.

STEP 04 Send Us the Details

Tell us the model, quantity and application — we will confirm availability and pricing.

Tooth Profile Comparison

Profile	Pitch	Tooth Shape	Best Suited For
S5M	5.00 mm	modified curvilinear (STS/STD)	Compact, lighter-duty metric precision drives
S3M	3.00 mm	modified curvilinear (STS/STD)	Miniature, space-critical drives
S8M	8.00 mm	modified curvilinear (STS/STD)	Heavier-duty metric drives
S14M	14.00 mm	modified curvilinear (STS/STD)	Heavy-duty, large pulley diameters
T5	5.00 mm	Trapezoidal	Metric trapezoidal alternative, same pitch class
MXL (inch)	2.032 mm	Trapezoidal	Miniature inch-pitch drives

Download S5M Belt Complete Size Chart & Dimensional PDF

All S5M timing belts are manufactured in accordance with the ISO 13050 standard for metric-pitch curvilinear (STD/STS) profile systems, ensuring full dimensional interchangeability with equivalent-profile S5M timing belts from other mainstream international manufacturers.

Applications

S5M belts are widely used wherever reliable timing and compact power transmission matter:

Industrial machinery: CNC equipment, automated production lines, conveyors, packaging machinery, textile machinery.
Office & consumer equipment: Printers, copiers, paper feed mechanisms, small appliances.
Precision drives: Robotics, medical equipment, measuring instruments, high-speed positioning systems.
Replacement drives: Direct swap on existing S5M pulley installations, restoring the original speed ratio without changing the pulleys.

Installation & Care

Inspect on receipt: surface clean and tidy, belt not twisted, teeth full and well-formed.
Never bend or crimp: bending damages the glass fiber tensile member and reduces belt strength.
Avoid scratches and chemicals: do not scratch the belt; avoid chemicals, especially strong oxidising acids; minimise prolonged oil and water exposure.
Reduce tension before removal: always release tension first. Never use unauthorised tools to pry the belt off under high tension.
Check pulley alignment: pulleys must be parallel and coplanar.
Tension correctly: just enough to prevent tooth jumping under maximum load. Over-tensioning shortens bearing life.
Keep the drive clean: remove oil, dust and debris. Replace at the first sign of tooth wear or cracking.

Frequently Asked Questions

What is an S5M timing belt?

The S5M synchronous belt is a metric-pitch member of the modified curvilinear tooth belt family. It uses a 5.00 mm tooth pitch, a 1.91 mm tooth height and a 3.41 mm belt thickness, and is engineered for compact, high-speed precision drives where accurate timing and quiet running are essential.

What is the difference between S5M and HTD 5M?

Both use a 5 mm pitch, but they are different profiles. S5M uses the STD/STS modified curvilinear tooth, while HTD 5M uses the HTD curvilinear tooth. Their tooth geometry and pulleys differ, so an S5M belt and an HTD 5M belt are not interchangeable.

What is the difference between S5M and T5?

Both have a 5 mm pitch. S5M is a curvilinear (half-round) profile with a 1.91 mm tooth height, while T5 is a trapezoidal profile with a 1.20 mm tooth height. S5M transmits more torque and runs more quietly, but the two need different pulleys.

How do I read an S5M belt model number such as 500-S5M-20?

The designation is pitch length – profile – width. So 500-S5M-20 means a 500 mm pitch line length, an S5M 5 mm curvilinear profile, and a 20 mm belt width. To find the number of teeth, divide the pitch length by the pitch: 500 / 5 = 100 teeth.

What widths and lengths are available?

We stock 280 standard S5M models in widths of 9, 15, 20 and 25 mm, with pitch lengths from 145 mm to 4360 mm. Custom widths and non-standard lengths can be manufactured on request.

What materials and construction do S5M belts use?

Every S5M belt uses a three-layer composite construction: a high-strength glass fiber tensile cord, a chloroprene rubber (CR) body, and a nylon 66 tooth facing for wear protection and low friction.

What applications are S5M timing belts used for?

S5M belts are used for compact, high-speed precision drives such as CNC equipment, automated production lines, conveyors, packaging and textile machinery, printers, copiers and paper feed mechanisms, robotics, medical and measuring instruments, and replacement drives on existing S5M pulleys.

Are S5M timing belts interchangeable with belts from other manufacturers?

Yes. Our S5M timing belts are manufactured to the ISO 13050 standard for metric-pitch curvilinear (STD/STS) profile systems and are fully dimensionally interchangeable with equivalent-profile S5M timing belts from other mainstream international manufacturers.

Need the Right S5M Belt for Your Drive?

All standard S5M lengths and widths are available. Tell us your pitch length and width — we will confirm the model and quote within one working day.

Request a Quote

Related Products: S3M STD Belt | T5 Timing Belt | Full Catalog

S5M Synchronous Belt

S5M Belt 145-4360mm, 5mm 9-25mm CR, ISO 13050 Timing Belt