YDY Three-Phase Asynchronous Motor Specifically Designed for Electric Screw Presses
1 Overview
The YDY series three-phase squirrel-cage induction motor (frame sizes 180–400) is a specialized motor designed for electric screw presses through a joint collaboration between our company and Huazhong University of Science and Technology. Increasingly popular and highly acclaimed by users, it is suitable for operation in the harsh industrial environments typical of the forging industry.
This series features high-quality materials and precision manufacturing, offering advantages such as high efficiency and energy conservation, low noise and vibration, reliable operation, and ease of installation and maintenance.
The power ratings, electrical performance, mounting dimensions, and tolerances of this series comply with the national standard GB 755 (*Rotating electrical machines – Rating and performance*), the International Electrotechnical Commission standard IEC 34-1 (*Rotating electrical machines – Rating and performance*), and relevant machinery industry standards.
The enclosure protection class for this series is IP44, IP54, or IP55.
The cooling method for this series is IC416.
The construction and mounting arrangement is IMV36 (side-mounted via feet with a top-mounted flange), in accordance with GB 997 and IEC 34-7 (*Classification of types of construction and mounting arrangements of rotating electrical machines*).
This catalog lists the technical data and mounting dimensions for various specifications of the YDY series (380V); derivative models with specifications such as 440V and 660V ratings are also available.
2 Scope of Application
This series of electric motors is designed to drive various electric screw presses (models include 160, 250, 315, 400, 630, 1000, 1600, and 2500). For special requirements, relevant technical data must be provided and a technical agreement signed at the time of ordering to serve as the basis for the motor's special design, thereby ensuring reliable operation.
Basic conditions for normal motor operation:
a Altitude not exceeding 1,000 m;
b Maximum ambient air temperature not exceeding 60°C; minimum ambient air temperature of -20°C (motors utilize rolling bearings);
c Monthly average maximum relative humidity of 90% during the most humid month, provided the monthly average minimum temperature does not exceed 25°C;
d Power supply frequency of 50 Hz ± 1%;
e Operating voltage fluctuation within ± 5% of the rated voltage;
f Motor rating is based on the intermittent periodic duty cycle (S3), involving frequent forward and reverse rotation.
3 Model Designation
The motor model designation consists of two parts arranged in sequence: the product code and the specification code. The product code represents the motor series, with meanings as follows:
Example:
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4 Structural Description
This series of motors features a compact structure; the frame and end shields are fabricated from high-quality welded steel. Excellent design and precision manufacturing ensure superior heat dissipation, while the frame and end shields offer high strength and rigidity.
The coils utilize a random-wound configuration with shortened end windings, resulting in high assembly quality and ease of maintenance.
The windings undergo a vacuum-pressure impregnation (VPI) process to enhance insulation reliability. Stator winding ends are neatly arranged and securely anchored.
The motor employs a cast-aluminum squirrel-cage rotor manufactured using a specialized process. The rotor bars, end rings, and fan blades are cast as a single integral unit, enhancing reliability and ensuring robust performance in harsh environments, alongside excellent electrical characteristics.
A specialized cooling structure is utilized to achieve optimal cooling performance.
The terminal box features a compact design, a high degree of protection, and reliable connection terminals. It offers flexible wiring options, allowing for cable entry from multiple directions.
5 Power Ratings
The motors are manufactured with the following rated power outputs:
22 kW, 30 kW, 55 kW, 90 kW, 160 kW, 250 kW.
The relationships between motor power, model, rotational speed, and moment of inertia shall comply with the specifications in Table 1:
Table 1
| Motor Model | power（kW） | Rotational speed（r/min） | Moment of inertia（kg·m²） | Electric Screw Press Models | Number of motors (units) |
| YDY180L-4 | 22 | 1470 | 0.19 | 315 | 2 |
| YDY200L-4 | 30 | 1470 | 0.33 | 400 | 2 |
| YDY250M-4 | 55 | 1470 | 0.86 | 630 | 2 |
| YDY315S-6 | 90 | 990 | 3.85 | 1000 | 2 |
| YDY355M-8 | 160 | 745 | 10.8 | 1600 | 2 |
| YDY400-8 | 250 | 745 | 20.1 | 2500 | 2 |
6 Description of the guaranteed value of electrical performance of the motor
The tolerance of the guaranteed electrical performance value of the motor should comply with the provisions of Table 2
When the power, voltage and frequency are rated, the current, efficiency, power factor and maximum torque multiple of the motor should comply with the provisions of Table 2.
Table 2
| Motor Model | power（kW） | Electric current（A） | efficiency（%） | Power factor（cosφ） | Maximum torque / Rated torque (multiple) |
| YDY180L-4 | 22 | 41 | 93.6 | 0.88 | 2.8 |
| YDY200L-4 | 30 | 55 | 94.1 | 0.88 | 2.6 |
| YDY250M-4 | 55 | 100 | 94.9 | 0.88 | 2.6 |
| YDY315S-6 | 90 | 165 | 95.5 | 0.87 | 2.6 |
| YDY355M-8 | 160 | 315 | 95.2 | 0.81 | 2.5 |
| YDY400-8 | 250 | 510 | 95.3 | 0.78 | 2.8
|
7 Ordering Information
Please specify the following details when placing an order:
(1) Motor Model: (YDY400-8)
(2) Rated Frequency: (50Hz)
(3) Rated Power: (250kW)
(4) Rated Voltage: (380V)
(5) Number of Poles: (8 poles)
(6) Protection Class: (IP54)
(7) Cooling Method: (IC416)
(8) Mounting Arrangement: (IMV36)
(9) Direction of Rotation: (Clockwise [viewed from the shaft extension end])
(10) Terminal Box Position: (Right side of the motor [viewed from the shaft extension end])
8 Important Notes
1. If operating conditions change or there are other special requirements, a separate technical agreement must be signed prior to the sales contract;
2. Due to technological advancements and revisions to relevant domestic and international standards, technical data and dimensions in this catalog are subject to change without prior notice; please request the official outline drawing from our company after placing an order.
