We break down the model "QJR-D," which adheres to China's machinery industry standards:

• Q: Stands for "Crane"

• J: Stands for "Reducer"

• R: Stands for "Two-Stage Transmission" (a gear form that automatically compensates for tooth alignment errors, offers smooth transmission, and high load-bearing capacity)

• D: Stands for "Type D" (a specific specification model in this series, typically referring to a branch with parameters such as center distance and transmission ratio)
  Main Features and Advantages

• The QJR-D reducer is the preferred choice for cranes because its design perfectly aligns with the operational characteristics of cranes:

  1. High Load-Bearing Capacity:

     • Herringbone Gear: Engages multiple teeth simultaneously, ensuring balanced force distribution and high torque transmission.

     • Medium-Hard Tooth Surface: High surface hardness, excellent wear resistance, and high contact fatigue strength, enabling it to withstand heavy loads and impact loads.

  2. Compact Structure and Light Weight:

     • Under the same power and speed ratio, medium-hard tooth surface reducers are smaller and lighter than traditional soft tooth surface reducers, helping to reduce the overall size and weight of cranes.

  3. High Transmission Efficiency:

     • High gear precision ensures smooth transmission, with efficiency typically around 94%~96%, effectively saving energy.

  4. Long Service Life:

     • The hardened tooth surface significantly enhances resistance to pitting and wear, providing a longer service life in demanding crane operations.

  5. Strong Versatility and Easy Maintenance:

     • The QJR series is a standard series with good part commonality and interchangeability, making it easy to procure spare parts and perform maintenance.
       

       Main Applications

       The QJR-D reducer is specifically designed for the hoisting mechanism of cranes and is also suitable for other mechanical transmission applications requiring heavy loads, low speeds, and high torque, such as:

       • Various types of bridge cranes

       • Gantry cranes

       • Metallurgical cranes

       • Port ship loaders, etc.
         The QJR-D medium-hard tooth surface reducer for cranes is a high-performance, standard reducer specifically designed for the heavy-duty conditions of cranes. Its herringbone gear and medium-hard tooth surface technologies ensure high reliability, long service life, and a compact structure under high loads, frequent starts and stops, and impact loads, making it a classic and critical component in China's crane manufacturing industry.