S8M-28T Aluminum Timing Pulley | 30mm Width, Custom Bore 12-28mm

PRODUCTS

CONTACT US

S8M Aluminum Timing Pulley – 28 Teeth, 30mm Belt Width, Type A, Custom Bore

Model Number
Check below, custom

S8M-28teeth 30mm belt width A type

S8M-28teeth 30mm belt width A type with keyway

Product Description

S8M Aluminum Timing Pulley – 28 Teeth, 30mm Belt Width, Type A, Custom Bore 12-28mm

The Apexcoupling S8M Aluminum Timing Pulley is a high-precision synchronous pulley designed for demanding power transmission applications requiring high torque, accuracy, and reliability. Featuring the S8M Super Torque (curvilinear) tooth profile with an 8mm pitch, this pulley delivers smooth, slip-free engagement with S8M timing belts for accurate synchronous transmission with constant rotation rate.

Manufactured from high-strength aluminum alloy (7000 series / duralumin) with 28 teeth and 30mm belt width, this Type A pulley offers a customizable bore diameter from 12mm to 28mm with H7 tolerance for precise shaft fit. The anodized surface treatment provides excellent corrosion resistance and wear protection. Ideal for conveyor systems, packaging machinery, printing equipment, textile machinery, CNC machines, factory automation, and robotics – where high torque and precision positioning are critical.

✅ S8M Super Torque curvilinear profile – high torque capacity, smooth operation, low backlash. 28 teeth – pitch diameter 71.30mm, outside diameter 69.93mm. 30mm belt width – standard industrial width. Type A – flangeless design for versatile mounting. Custom bore 12-28mm (H7 tolerance) – precision shaft fit. High-strength aluminum alloy – lightweight, corrosion-resistant. Anodized finish – enhanced durability. OEM/ODM customization – custom bore, keyway, surface treatment.

Key Technical Specifications

Parameter	Value
Brand	Apexcoupling
Product Name	S8M Aluminum Timing Pulley
Tooth Profile	S8M Super Torque (curvilinear) – 8mm pitch [6†L18-L20][8†L12]
Number of Teeth	28 [1†L4][7†L10]
Pitch Diameter (P.D.)	71.30 mm [1†L13][4†L18][6†L33]
Outside Diameter (O.D.)	69.93 mm [1†L5][4†L18][6†L35][7†L23]
Belt Width	30 mm [3†L6][7†L21][8†L12]
Pulley Shape	Type A (flangeless) [10†L6]
Material	High-strength aluminum alloy (7000 series / duralumin) [2†L14][8†L17][9†L5]
Surface Treatment	Clear anodized (standard); hard anodized, black oxide, electroless nickel plating (optional) [8†L18-L19][10†L2]
Bore Diameter	Customizable: 12, 14, 15, 16, 17, 18, 19, 20, 22, 24, 25, 28 mm [2†L19][8†L19-L20]
Bore Tolerance	H7 [7†L11]
Keyway	Optional (custom)
Set Screws	Optional – M6 × 5 for 18-30mm bore [6†L29]
Flange	No (Type A) [7†L11]
Hub Diameter (Dm)	55 mm (approx.) [1†L5]
Face Width (F)	38 mm (approx.) [1†L5]
Overall Width (L)	48 mm (approx.) [1†L6]
CAD	2D & 3D available [9†L10]
Customization	OEM, ODM – custom bore, keyway, surface treatment, flange option
Applicable Industries	Conveyor systems, packaging machinery, printing equipment, textile machinery, CNC machines, factory automation, robotics, medical devices, material handling [5†L7-L9]
Place of Origin	Guangdong, China

S8M Profile – Super Torque Curvilinear Teeth

The S8M (Super Torque) profile features a curvilinear (arc) tooth design that provides superior performance compared to traditional trapezoidal profiles:

Feature	S8M Curvilinear Profile	Trapezoidal Profile (T/AT)
Tooth shape	Arc / curvilinear	Straight-sided
Load capacity	Higher – better stress distribution	Moderate
Smoothness	Excellent – quiet operation	Good
Positioning accuracy	Excellent – minimal backlash	Good
Speed capability	High	Moderate
Best for	High torque, precision, high speed [5†L31-L32]	Conveyance, continuous running [5†L12-L14]

✅ Choose S8M for applications requiring high torque transmission, precise positioning, and smooth, quiet operation [5†L31-L32].

S8M-28T – Dimensional Specifications

Parameter	Value
Tooth Profile	S8M (Super Torque)
Pitch	8.00 mm [6†L20]
Number of Teeth	28 [7†L10]
Pitch Diameter (P.D.)	71.30 mm [1†L13][4†L18][6†L33]
Outside Diameter (O.D.)	69.93 mm [1†L14][4†L18][6†L35][7†L23]
Belt Width	30 mm [7†L21][8†L12]
Hub Diameter (Dm)	55 mm (approx.) [1†L5]
Face Width (F)	38 mm (approx.) [1†L5]
Overall Width (L)	48 mm (approx.) [1†L6]
Bore Range	12-28 mm (H7) [8†L19-L20]

Product Structure

Pulley Body – Precision-machined from high-strength aluminum alloy (7000 series / duralumin) [2†L14][8†L17][9†L5].
S8M Tooth Profile – Curvilinear arc teeth for high torque, smooth engagement, and low backlash [5†L31-L32].
Bore – Customizable 12-28mm with H7 tolerance for precise shaft fit [7†L11][8†L19-L20].
Anodized Surface – Clear anodized (standard) for corrosion resistance and wear protection [8†L18][10†L2].
Type A (Flangeless) – No flanges for versatile mounting in tight spaces [10†L6].

💡 How it works: The S8M timing pulley engages with an S8M timing belt through its curvilinear teeth, providing accurate, slip-free synchronous transmission. The pulley is mounted on a shaft via the custom H7 bore, with optional keyway and set screws for positive torque transmission. The lightweight aluminum construction reduces inertia, while the anodized finish provides corrosion resistance.

Product Features & Advantages

Advantage	Benefit
S8M Super Torque Profile	High torque capacity, smooth operation, low backlash [5†L31-L32]
28 Teeth	Pitch diameter 71.30mm – ideal for medium to heavy-duty applications [6†L33]
30mm Belt Width	Standard industrial width – compatible with common S8M belts [3†L6][7†L21]
Type A (Flangeless)	Versatile mounting – fits in tight spaces without flange interference [10†L6]
Custom Bore 12-28mm	Precision fit for various shaft sizes – H7 tolerance [8†L19-L20]
Aluminum Alloy (7000 Series)	Lightweight, corrosion-resistant, high strength-to-weight ratio [2†L14][8†L17]
Anodized Surface	Enhanced corrosion resistance and wear protection [8†L18][10†L2]
High Precision	CNC machined – concentricity and accuracy guaranteed
OEM Customization	Custom bore, keyway, surface treatment, flange options
CAD Support	2D & 3D drawings available [9†L10]

Applications

Conveyor Systems – Material handling, assembly lines, product transport [5†L7-L9]
Packaging Machinery – Wrapping machines, carton sealers, labeling equipment [5†L7-L9]
Printing Equipment – Paper feed, register control, screen printing [5†L18-L19]
Textile Machinery – Spinning, weaving, finishing equipment [5†L18-L19]
CNC Machines – Precision positioning, feed drives [5†L25]
Factory Automation – Linear drives, pick-and-place systems, robotics [5†L7]
Food Packaging – Hygienic, corrosion-resistant conveying [5†L25]
Medical Devices – Precision imaging, diagnostic equipment

Why Choose Apex Coupling for S8M Timing Pulleys?

Advantage	Description
Factory Direct	Competitive B2B pricing – no middlemen
Premium Aluminum Alloy	7000 series / duralumin – lightweight, high strength [8†L17]
S8M Super Torque Profile	High torque, precision, smooth operation [5†L31-L32]
Anodized Finish	Corrosion resistance and durability [8†L18]
Custom Bore 12-28mm	Precision H7 fit for your shaft [8†L19-L20]
OEM Customization	Custom bore, keyway, surface treatment, flange
CAD Support	2D & 3D drawings available [9†L10]
Fast Delivery	Stocked items available for quick shipment

FAQ

Q: What is an S8M timing pulley?
A: An S8M timing pulley is a synchronous pulley with an 8mm pitch curvilinear (Super Torque) tooth profile. It provides high torque transmission, smooth operation, and precise positioning for timing belt drive systems [5†L31-L32].

Q: What is the outside diameter of a 28-tooth S8M pulley?
A: The outside diameter is 69.93mm and the pitch diameter is 71.30mm [1†L14][4†L18][6†L35][7†L23].

Q: What belt width does this pulley support?
A: This pulley supports 30mm belt width [3†L6][7†L21][8†L12]. Other widths (15mm, 25mm, 40mm) are available upon request [8†L12].

Q: What is the bore diameter range?
A: Custom bore diameters from 12mm to 28mm with H7 tolerance [8†L19-L20]. Standard options include 12, 14, 15, 16, 17, 18, 19, 20, 22, 24, 25, and 28mm.

Q: What material is used?
A: The pulley is manufactured from high-strength aluminum alloy (7000 series / duralumin) [2†L14][8†L17][9†L5].

Q: What surface treatment is available?
A: Standard is clear anodized. Optional treatments include hard anodized, black oxide, and electroless nickel plating [8†L18-L19][10†L2].

Q: What is Type A pulley shape?
A: Type A is a flangeless design with no flanges on either side, suitable for versatile mounting in tight spaces [10†L6].

Q: Can I get a custom bore or keyway?
A: Yes. We offer OEM/ODM customization – custom bore diameter, keyway, set screw holes, and surface treatment.

Q: What are the common applications?
A: Conveyor systems, packaging machinery, printing equipment, textile machinery, CNC machines, factory automation, and robotics [5†L7-L9][5†L18-L19].

Q: What is the difference between S8M and HTD 8M?
A: Both have 8mm pitch with curvilinear profiles. S8M is the “Super Torque” profile developed by Mitsuboshi Belting, while HTD 8M is the standard high-torque drive profile from Gates. They are similar but with slight differences in tooth geometry – compatibility should be verified with the belt manufacturer.