I. Product Introduction

The ZDY, ZLY, and ZSY series are three-stage external meshing involute cylindrical gear reducers. They are standardized series of hard-faced gear reducers as stipulated by the Chinese National Standard (GB/T 19073-2008). They are upgraded versions of the original ZD, ZL, and ZS series.

These reducers are manufactured from high-quality alloy steel forgings through precision processing techniques such as carburizing, quenching, and gear grinding. Their gears feature high hardness (tooth surface hardness ≥ HRC 54-62) and high precision (up to GB/T 10095 Grade 6), giving them a load capacity far exceeding that of traditional soft-faced gear reducers. Due to their cylindrical shape, they are often called "Cylindrical Gear Reducers" or "Hardened and Ground Gear Units".

• ZDY: Single-stage reduction

• ZLY: Two-stage reduction

• ZSY: Three-stage reduction

II. Product Advantages

1. High Load Capacity: The use of high-strength alloy steel and hard-facing processes provides excellent resistance to pitting and wear, enabling them to handle heavy loads and shock loads.

2. High Transmission Efficiency: Single-stage efficiency can reach over 98%, and the comprehensive efficiency of a three-stage unit remains above 94%, offering significant energy savings.

3. Long Service Life: Precision manufacturing and hardening treatments result in minimal gear wear, leading to a design life much longer than that of soft-faced reducers.

4. Compact Structure & Small Size: For equivalent torque and ratio, they are smaller and lighter than soft-faced reducers, saving installation space.

5. Smooth Operation & Low Noise: High-precision gear grinding ensures smooth meshing, reducing operational noise and vibration.

6. High Versatility & Easy Maintenance: Standardized and serialized design makes them easy to select, interchange, and maintain.

III. Main Technical Parameters

• Specification Range:

  • Center Distance (a): ZDY: 80 - 800 mm; ZLY: 100 - 1000 mm; ZSY: 160 - 1000 mm (Varies by manufacturer)

• Transmission Ratio (i):

  • ZDY (Single-stage): 1.25 - 6.3

  • ZLY (Two-stage): 6.3 - 31.5

  • ZSY (Three-stage): 31.5 - 180

• Input Power (P1): Up to several thousand kilowatts (dependent on size and ratio).

• Output Torque (T2): Ranges from hundreds to hundreds of thousands of Newton-meters (N.m).

• Allowable Radial Load: Must be checked against the manufacturer's selection manual and depends on the mounting style.

IV. Typical Applications

This series of reducers is a core component for power transmission in industrial fields and is widely used in:

• Conveying Equipment: Belt conveyors, bucket elevators, scraper conveyors.

• Metallurgical Machinery: Rolling mills, straightening machines, wire drawing machines.

• Mining Machinery: Crushers, ball mills, coal mills.

• Chemical Machinery: Mixing equipment, extruders.

• Construction Machinery: Tower cranes, concrete batching plants.

• General Industry: Any application requiring high power, high torque, and stable transmission.