Tight on Space for Belt Conveyors? R Series Coaxial Helical Gearmotor

◆We’ve helped customers across Southeast Asia, the Middle East, Africa, and South America — warehouses, distribution centers, manufacturing plants — with R series coaxial gearmotor solutions for their belt conveyors. Why? Because when you are running a 24/7 conveyor line, you need a drive that is compact, efficient, and reliable.

 The R series is a coaxial helical gearmotor – input and output shafts are on the same axis. This simple design gives you three big advantages: shorter axial length than parallel shaft units, higher efficiency than worm gearboxes, and no unnecessary right-angle stages.

 But is it always the right choice? Let’s compare it with other common series for belt conveyor applications.

▼R vs. Other Series: When to Choose Which?

▼Summary for Belt Conveyor Applications:

✅ Choose R series when:

● Axial installation space is limited (R is much shorter than F).

● You do not need right-angle output.

● You do not need self-locking.

● Power is within 0.12kW – 200kW (typical 0.5-90kW for light/medium belt conveyors).

● You want high efficiency (≥95%) for 24/7 operation.

✅ Choose F series when:

● You have plenty of axial space and need higher radial load capacity (e.g., heavy-duty roller conveyor with large belt tension).

✅ Choose K series when:

● You need a right-angle output (motor mounted perpendicular to conveyor axis).

✅ Choose S, RV, or WP when:

● You need self-locking for incline or hoist applications (but accept lower efficiency).

✅ Choose ZY when:

● Power exceeds 200kW, or you need a very heavy-duty parallel shaft solution.

📌Key Technical Considerations for Belt Conveyor Drives

1. Radial Load from Belt Tension

When you mount a pulley or sprocket directly on the gearbox output shaft, the belt tension creates a radial load (overhung load). For V-belt drives, the radial load factor fr = 1.5; for flat belts, fr = 2.5.

Formula: Fr = 2 × Mr × fr / d (N)

Where:

● Mr = torque at the output shaft (N·m)

● d = pitch diameter of pulley (m)

Then multiply Fr by the total service factor fA (which includes load type, daily operating hours, starts per hour, and ambient temperature). The result must be less than or equal to the permissible radial load FRa listed in the R series selection table.

Real example: A belt conveyor in a Thai warehouse used a V-belt drive with Mr = 200 N·m, d = 0.2 m. Fr = 2×200×1.5/0.2 = 3000 N. With fA = 1.5 (16h/day, moderate shock), required = 4500 N. The R89 selection table shows FRa = 5200 N at the shaft midpoint – acceptable.

2. Service Factor fA for Belt Conveyors

Then multiply by fAc (starts per hour):

● <10 starts/h: fAc = 1.0

● 10-100 starts/h: fAc = 1.15

● 100 starts/h: fAc = 1.25

Also consider ambient temperature: above 30°C, multiply by 1.1-1.5.

3. Motor Selection for Belt Conveyors

Standard recommendation: Use IE3 or IE4 efficient motors for continuous operation to reduce long-term electricity cost.

For explosive environments (e.g., coal mines, grain handling):
You must select an explosion-proof motor. Consult your motor supplier based on the zone classification (Zone 1, Zone 2, etc.) and local standards (ATEX, IECEx, NEC).

For frequent start/stop or speed regulation:
When starts per hour exceed 10, or you need variable belt speed, we recommend a variable frequency drive (VFD) – compatible with inverter-duty motors. The R series works perfectly with VFDs.

Ambient temperature: Standard range is -10°C to +40°C. Outside this range, special lubricants or heaters may be required – contact our technical team.

📍 Case Studies

Case 1: Warehouse Belt Conveyor – Vietnam

Customer: A logistics center in Ho Chi Minh City.

Application: 12m long horizontal belt conveyor for cartons, 16h/day, 8 starts/hour.

Challenge: Limited axial space – only 350mm available between conveyor frame and wall. A parallel shaft (F series) would not fit.

Solution: HelmeDrive R series R89, ratio 1:25, with foot mounting.

Result: Installed within the tight space. Motor temperature stable at 65°C. Radial load calculated and verified against FRa. Customer later ordered 20 units for their new warehouse.

Case 2: Food Processing Incline Conveyor – Nigeria

Customer: A food factory in Lagos.

Application: 8° incline conveyor for bagged flour, 24h/day.

Challenge: The customer initially considered a worm gearbox (RV) for self-locking, but the high continuous runtime made efficiency critical.

Solution: We recommended R series (no self-locking needed – the incline was gentle and a backstop was installed on the head pulley). R series efficiency ≥95% vs ~70% for worm.

Result: Energy saving of approximately 25% compared to their previous worm gear units. Payback period less than 8 months.

Case 3: Mining Belt Conveyor – South Africa

Customer: An aggregate plant outside Johannesburg.

Application: Belt conveyor for crushed stone, heavy shock load, 12h/day.

Challenge: The required power was 110kW, near the upper limit of R series (200kW). But the customer had limited axial space and wanted a coaxial solution.

Solution: HelmeDrive R series R169 with ratio 1:20, using a 110kW IE3 motor. Radial load carefully calculated (chain drive, fr=1.25).

Result: Running reliably for 18 months. No bearing or seal failure. The compact footprint allowed easier integration into their existing plant layout.

↓Technical Support 

What we do offer:

● Remote video support for installation, alignment, and troubleshooting (within working hours of your time zone)

● Selection guidance including radial load calculation and service factor verification

● Drawings for foot and flange mounted versions

● Compatible replacements for commonly used European brands’ inline gearmotors (mounting dimensions interchangeable for many sizes)

※ Why Customers Choose HelmeDrive R Series for Belt Conveyors?

🔹 Truly compact – coaxial design saves axial space.
🔹 High efficiency – ≥95% reduces energy cost for 24/7 operation.
🔹 Transparent radial load data – no guesswork.
🔹 Flexible motor options – standard, explosion-proof, VFD-ready, brake motor.
🔹 No unnecessary stages – no bevel gear, no worm – just simple, reliable helical gears.

★ Get a Selection Proposal for Your Conveyor Drive

Send us your belt conveyor parameters:

● Motor power or output torque

● Output speed (or belt speed + pulley diameter)

● Daily operating hours and starts per hour

● Ambient temperature

● Pulley pitch diameter (for radial load calculation)

📩 Sales inquiry: shawn.zhu@helmedrive.com

�FAQ

Q1: Can I use the R series for an inclined belt conveyor that requires self-locking?
A: No. The R series helical gearbox is not self-locking. For incline conveyors, you need either a brake motor or a backstop device on the head pulley. Alternatively, consider the S series (helical-worm) if self-locking is mandatory and you accept lower efficiency.

Q2: How do I know if the radial load from my belt drive is within the limit?
A: Use the formula Fr = 2 × Mr × fr / d. Then multiply by your total service factor fA. Compare the result with the FRa value in the R series selection table (at shaft midpoint or off-center with conversion factor). If you are unsure, send us your numbers – we will verify for you.

Q3: What is the difference between R series and commonly used European inline gearmotors?
A: Mounting dimensions (foot and flange) are designed to be compatible for many sizes. Efficiency and radial load capacity are comparable. The main difference is lead time and local support. We provide a direct replacement option with full drawings upon request.

Q4: Can the R series be used in a coal mine with explosion-proof requirement?
A: Yes, but you must fit an explosion-proof motor. The gearbox itself does not have an explosion-proof rating. Choose a motor with the appropriate ATEX / IECEx certification for your zone. Contact your motor supplier for the correct specification.

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✦ HelmeDrive.com - Professional manufacturer of industrial gearbox in China ✦

✦ Gear Motor | Gear Unit | Industrial Gearbox ✦

📩 Contact us for a comparison quote:
Email: shawn.zhu@helmedrive.com| WhatsApp:  [+86-13196785788]