Categories: معدنکاری

گیربکس حلزونی برای سیستم‌های نوار نقاله تسمه‌ای

Belt conveyors are the circulatory system of Australia’s mining and bulk-materials industry, moving millions of tonnes of coal, iron ore, grain, and mineral aggregate every year. Behind every reliably running conveyor is a precisely selected drive unit — and the گیربکس حلزونی has earned its dominant position through a combination of self-locking geometry, compact right-angle output, and robust high-torque delivery.

The self-locking characteristic is particularly critical on inclined conveyors: when power is removed, the irreversible worm geometry prevents the loaded belt from reversing under gravity. This eliminates the need for a separate backstop or motorised brake on many installations, simplifying the mechanical design and reducing maintenance exposure.

Standard NMRV and NRV series aluminium or ductile-iron worm gearboxes are available in frames from 025 to 150, providing output torques from 2.6 N·m up to 4,200 N·m and reduction ratios from 5:1 to 100:1 in a single compact stage. Two-stage tandem configurations extend this to 3,600:1.

کاربردها و موارد استفاده در صنعت

In a typical belt conveyor drive arrangement, the گیربکس حلزونی sits between the electric motor and the conveyor head drum. Key application points include:

Head-end drive units on horizontal conveyors — steady torque, self-lock on stop
Inclined conveyor drives — self-locking prevents roll-back under loaded belt weight
Take-up winch drives — precise low-speed tension control on counterweight systems
Belt weigh feeder drives — accurate, vibration-free low-speed output

Materials: Worm shaft in surface-hardened alloy steel 20CrMnTi (HRC 58–62). Worm wheel in centrifugally cast phosphor bronze. Housing in ductile iron GGG40 with IP65 dust-and-jet-water sealing.

Working principle: The helical worm thread engages the bronze wheel teeth at 90°. Back-driving from the wheel side is geometrically prevented when the lead angle is below the friction angle — this is the self-locking mechanism at the heart of safe conveyor operation.

مشخصات فنی و راهنمای انتخاب

از جدول زیر برای شناسایی مدل مناسب استفاده کنید. پارامترهای کلیدی شامل نسبت کاهش، گشتاور خروجی، ابعاد شفت و جنس محفظه است. همیشه از مقادیر صحیح استفاده کنید. ضریب خدمات (SF) برای چرخه کاری شما.

پارامتر	محدوده/مقدار معمول	یادداشت‌های انتخاب
نسبت	5:1 – 100:1 (single-stage)	Two-stage tandem available up to 3,600:1
گشتاور خروجی	2.6 – 4,200 N·m	Dependent on frame size 025–150
Input Shaft Diameter	11 – 42 mm	کمیسیون مستقل انتخابات ۶۰۰۳۴ standard flange sizes B5/B14
Output Shaft Diameter	14 – 50 mm (solid)	Hollow bore available from frame 030 up
جنس بدنه	Aluminium alloy / Ductile iron GGG40	Stainless steel 316 available on request
Mounting Type	Foot / Flange / Shaft-mounted	All standard orientations F1–F8
کلاس حفاظت	IP65 standard; IP66 / IP69K optional	Specify at order for outdoor / washdown duty

► ضریب خدمات (SF): Uniform load SF=1.0 | Moderate shock SF=1.25–1.5 | Heavy shock / 24 h continuous SF=1.75–2.0

► دمای محیط: Standard units rated –10°C to +40°C. Australian high-ambient sites (>45°C) require high-temperature lubricant and 15% thermal derating.

گیربکس حلزونی سری NMRV / NRV

Available in frame sizes 025 through 150. Single-stage reduction ratios 5:1 to 100:1. Output torque up to 4,200 N·m. Aluminium or ductile iron housing. IEC B5/B14 motor flange. IP65 standard, IP66/IP67 optional. Synthetic or mineral oil lubrication.

استانداردهای انطباق و کیفیت

✓ ISO 9001:2015
دارای گواهینامه سیستم مدیریت کیفیت. هر واحد تحت سیستم مدیریت کیفیت مستند با قابلیت ردیابی کامل، تولید و بازرسی می‌شود.

✓ CE Certification
دارای نشان CE برای دستورالعمل ماشین‌آلات اتحادیه اروپا. به طور گسترده در پروژه‌های مهندسی استرالیا و نیوزیلند پذیرفته شده است.

✓ رابط موتور IEC 60034
ابعاد فلنج و شفت استاندارد IEC. سازگاری نصب مستقیم با تمام برندهای اصلی موتور.

✓ IP65 / IP66 Protection
مقاوم در برابر گرد و غبار و پاشش آب با فشار بالا. استاندارد برای نصب در فضای باز استرالیا.

مطالعات موردی

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Case Study 1 — Open-Cut Coal Mine, Hunter Valley NSW

معدنکاری
Inclined Belt Conveyor

نقطه درد مشتری: A coal mine was experiencing rollback on a 15° inclined conveyor each time the belt tripped under overload. The mechanical backstop failed twice in six months, causing 18 hours of downtime per incident.

راه حل: NMRV-110 worm gearboxes (ratio 60:1, ductile iron, IP65) were installed on both drive stations. The inherent self-locking eliminated the need for the external backstop entirely.

نتیجه: Zero rollback incidents over 14 months. Annual maintenance cost reduced by 35%. The mine standardised the same model across three further inclined conveyors on site.

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Case Study 2 — Mineral Processing Plant, Western Australia

معدنکاری
Horizontal Ore Conveyor

نقطه درد مشتری: A WA iron ore processor needed to replace an ageing helical gearbox generating 74 dB(A) of gear noise, with oil changes every 1,500 hours due to worn lip seals.

راه حل: NRV series worm gearbox (ratio 40:1, 1,800 N·m) with upgraded FKM double-lip seals and synthetic PAO gear oil.

نتیجه: Operating noise reduced to 61 dB(A). Oil change interval extended to 5,000 hours. Zero seal leaks during two 12-month inspection cycles.

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Case Study 3 — Grain Handling Terminal, Port of Geraldton WA

Bulk Handling
Belt Weigh Feeder

نقطه درد مشتری: A grain terminal’s weigh feeder was overspeeding by up to 8%, causing inaccurate throughput measurement and regulatory compliance issues.

راه حل: NMRV-063 worm gearboxes (ratio 80:1) replaced the helical-bevel units. Smooth, low-backlash output eliminated speed hunting corrupting the load cell signal.

نتیجه: Throughput accuracy improved to within 0.3% of certified scale. Port authority compliance reinstated within one week.

NMRV / NRV series worm gearboxes — frame sizes 025 to 150, manufactured to ISO 9001:2015

چرا ما را انتخاب کنید؟

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بیش از ۲۰ سال سابقه تولید
تولید دارای گواهینامه ISO از سال ۲۰۰۳. گیربکس‌های حلزونی به بیش از ۶۰ کشور ارسال می‌شوند.

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پشتیبانی فنی از راه دور
تشخیص بیماری از طریق تماس ویدیویی در سراسر مناطق زمانی استرالیا. پاسخ سریع بدون نیاز به مراجعه حضوری.

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سفارشی سازی OEM / ODM
شفت‌های غیر استاندارد، سوراخ توخالی، فلنج‌ها و نسبت‌های سفارشی. بررسی کامل نقشه موجود است.

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ارزش مستقیم کارخانه
بدون حاشیه سود توزیع‌کننده. قیمت‌گذاری شفاف بر اساس حجم فروش با صرفه‌جویی قابل توجه در سفارش‌های تکراری.

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موجودی و ارسال سریع
فریم‌های استاندارد NMRV/NRV در انبار موجود است. سفارش‌های فوری برای حمل و نقل سریع پردازش می‌شوند.

سوالات متداول

▼ What is the difference between NMRV and NRV worm gearboxes for conveyor applications?

NMRV units feature an aluminium alloy housing — lighter and suited to lighter-duty or indoor drives. NRV units use cast iron — greater rigidity and thermal mass, preferred for continuous heavy-load mining conveyors. Both share identical internal geometry and are interchangeable in mounting footprint within the same frame size.

▼ How do I calculate the required reduction ratio for my belt conveyor?

Required ratio = Motor RPM ÷ Required drum RPM. Drum RPM = (Belt speed m/s × 60) ÷ (π × drum diameter m). For example, 1.5 m/s belt on a 400 mm drum needs 71.6 RPM. With a 1,400 RPM motor, required ratio is 19.6:1 — select 20:1 or 25:1. Contact our engineering team for a free calculation.

▼ Does a worm gearbox on an inclined conveyor require a separate anti-rollback device?

For inclinations up to approximately 20° and loads within the rated self-locking torque, worm geometry alone provides sufficient anti-rollback protection. Above 20° inclination or for very high-inertia belt loads, a supplementary backstop or brake is recommended as safety redundancy.

▼ What IP protection rating should I specify for a mine-site belt conveyor gearbox?

IP65 is the minimum for all open mine-site conveyor applications. For conveyors near water sprays, dewatering areas, or underground wet zones, specify IP66 or IP67. Our standard NMRV/NRV range is IP65 as standard, with IP66 and IP67 available as factory options.

▼ What lubricant is recommended for worm gearboxes on mining conveyors in hot Australian climates?

Standard mineral ISO VG 220–460 is suitable for ambient temperatures up to 35°C. For outback sites regularly exceeding 40°C, synthetic PAO ISO VG 320 is recommended — it reduces internal operating temperature by 8–12°C and extends the oil change interval from 2,000 hours to 5,000+ hours.

▼ Can worm gearboxes be used for reversing conveyor applications?

Yes — worm gearboxes can be driven in both directions at the same rated torque. The self-locking feature applies in both directions. For applications requiring free coasting in reverse, a low-lead-angle (non-self-locking) ratio must be specifically selected. Consult our technical team to confirm self-locking status for your chosen ratio.