ZJP-300 Roots Vacuum Pump – High-Efficiency Mechanical Booster Pump

ZJP-300 Roots Vacuum Pump – High-Efficiency Mechanical Booster Pump

ZJP-300 Roots vacuum pump is a high-performance mechanical booster pump designed for medium to high vacuum applications. As part of the ZJP series, this positive displacement pump utilizes two figure-8 shaped rotors rotating synchronously in opposite directions within the pump chamber to achieve efficient gas extraction. With a nominal pumping speed of 300 L/s, the ZJP-300 delivers exceptional performance for a wide range of industrial vacuum processes.

The ZJP series is an advanced derivative of the standard ZJ Roots pump, featuring a built-in bypass (relief) valve that provides automatic overload protection. This innovative design significantly reduces the operating load under high differential pressure conditions, protecting the motor from overloading and extending the pump’s service life. The pump is available in various configurations from different manufacturers, including models from Zhejiang Qiushi, Sichuan Huaxin Nanguang, and Shandong Zhenhong, among others.

The pump cannot operate alone and must be used in series with a backing pump, such as a rotary vane pump, liquid ring pump, or slide valve pump, to achieve optimal vacuum levels.

How it works?

ZJP-300 operates on a simple yet highly effective principle. Inside the pump chamber, two figure-8 shaped rotors rotate in opposite directions at high speed, driven by a pair of synchronized timing gears. The rotors maintain a precise clearance with each other and with the pump housing, enabling frictionless, oil-free operation within the pump cavity. As the rotors turn, the volume on the intake side expands, drawing gas into the chamber. The gas is then trapped, compressed, and expelled through the exhaust port as the rotors continue their rotation, completing the pumping cycle.

A key feature of the ZJP series is the integrated bypass (overflow) valve. When the pressure difference between the inlet and outlet exceeds a preset safe value, the valve automatically opens, allowing some gas to recirculate back to the inlet side. This mechanism reduces the load on the pump and prevents motor overload, ensuring safe and reliable operation even under challenging conditions.

Technical Specifications:

Features & Advantages

1. Built-in Overload Protection
The ZJP-300 is equipped with an integrated bypass (relief) valve that automatically activates when the pressure difference exceeds a safe threshold, preventing motor overload and protecting the pump from damage. This feature ensures safe and reliable long-term operation.

2. Oil-Free Pump Cavity
Since the rotors operate without contact inside the pump chamber, no lubrication is required within the pumping cavity. This eliminates the risk of oil vapor contamination of the vacuum system, making the pump ideal for clean and sensitive applications.

3. High Pumping Speed Across a Wide Pressure Range
The ZJP-300 delivers a high pumping speed even at lower inlet pressures, significantly enhancing the overall pumping efficiency of the vacuum system.

4. Low Vibration and Low Noise
The rotors are precision-machined using high-quality CNC equipment and undergo rigorous dynamic balancing. Combined with high-precision bearings and timing gears, this results in smooth, stable operation with minimal vibration and low noise levels (80–82 dB(A)).

5. Fast Start-Up and Quick Evacuation
The pump starts quickly and can reach the ultimate vacuum in a short time, minimizing downtime and improving process efficiency.

6. Low Maintenance and Long Service Life
With no contact between moving parts inside the pump cavity, mechanical wear is minimal. The pump features a robust design with high-quality components, resulting in low maintenance requirements and a long operational lifespan.

7. Compact and Space-Saving Design
The ZJP-300 features a horizontal, compact structure that occupies minimal floor space, making it easy to integrate into existing vacuum systems.

8. Insensitive to Dust and Water Vapor
The pump is not sensitive to small amounts of dust or water vapor in the gas stream, making it suitable for demanding industrial environments.

9. High-Precision Manufacturing
The pump body, side covers, and rotors are machined on high-precision CNC equipment, ensuring excellent geometric symmetry, uniform rotor clearance, and superior interchangeability of parts for easy maintenance.

Applications:

ZJP-300 Roots vacuum pump is widely used across numerous industries and processes, including:

When paired with a water ring vacuum pump as a backing pump, the ZJP-300 is particularly effective for applications requiring the removal of large amounts of water vapor and condensable gases.

For detailed quotations, customized configurations, or technical support, please contact your local supplier or visit our product inquiry page.