Internal Structure Frontside
Internal Structure Backside
Working Principle
In an ideal air compression process, the power needed for single-stage pressure transmission equals the total power required for multi-stage compression. However, real-world applications face increased working power due to factors such as coupling transmission power loss, bearing friction, and liquid viscosity cooling effects. By reducing the compression ratio of each stage, we can diminish useless power, making the total power required for multi-stage compression less than that for single-stage compression.
The two-stage screw air compressor features a two-stage rotary screw system. Each stage includes an active screw and a passive screw. The active screw drives the passive screw via an external power transmission device. The first stage operates with a low-pressure rate screw group, while the second stage uses a high-pressure rate screw group. A sealing air film envelops each screw. Throughout the rotation, the gas undergoes three processes: suction, pressurization, and exhaust.
First Stage Compression: The first stage utilizes a low-pressure rate screw group to squeeze the gas between them. The gas enters the screw compression chamber via the suction valve. Under the high-speed rotation of the screw rotor, the gas gets gradually squeezed out and transferred to the second stage.
Second Stage Compression: In the second-stage screw group, the gas is directed into a tighter screw space and compressed under higher temperature and pressure. The exhaust valve opens to expel the high-pressure gases from the system.
Natural air passes through the air filter to enter the first stage of compression, mixing with a small amount of lubricating oil in the compression chamber. The mixed gas compresses to the interstage pressure. The compressed gas then enters the cooling channel, encountering a large amount of oil mist, which drastically reduces its temperature. The cooled, compressed gas moves to the second-stage rotor for two-stage compression, culminating in the final exhaust pressure. The compressor discharges the gas through the exhaust valve, completing the entire compression process.
Water-cooled compressors utilize water as a cooling medium, circulating it internally to perform a dual function: cleaning and enhancing lubrication. This process significantly extends the life of friction-prone parts. During operation, the cooling water absorbs and dissipates heat from the cylinder and compressed gas, effectively lowering the exhaust temperature and reducing power consumption. This leads to substantial operating cost savings for the air compressor. However, it is crucial to address potential scaling issues within the water cooling system to maintain optimal performance.
1) Exceptional Efficiency of PM Motor:The permanent magnet (PM) motor boasts a wider constant torque and weak magnetic range. It outperforms regular motors by 20-30% in efficiency. Notably, the PM motor maintains its high efficiency even when operating outside the rated frequency, ensuring consistent performance under varying conditions.
2) Maintenance-Free Motor:Featuring a design devoid of internal bearings, the permanent magnet motor eliminates the need for costly bearing maintenance and replacements, making it a hassle-free solution.
3) Integrated Frequency Converter:This air compressor utilizes a top-tier frequency system developed in China, offering a broad speed regulation range and high precision. It adjusts the frequency based on the user's actual gas demand, resulting in remarkable energy savings.
4) Zero Transmission Loss:The integrated shaft structure directly connects the permanent magnet motor and compressor, creating a compact design devoid of couplings or other transmission parts. This ensures a 100% transmission efficiency.
5) Smooth Variable Frequency Start:The motor's variable frequency start and soft start feature significantly minimize impact on power grid equipment, preventing any damage to electrical systems.
6) Enhanced Energy Efficiency:With a frequency conversion range spanning from 25% to 100%, compared to the ordinary range of 50% to 100%, this compressor achieves over 30% energy savings compared to fixed-speed models. It also offers approximately 5% more energy savings than standard variable frequency compressors. Larger fluctuations in system gas consumption lead to even more pronounced energy savings.
7) Unique Two-Stage Compression Air End:The air end of this two-stage compression screw machine is uniquely designed, integrating the first and second-stage compression rotors within a single casing. Each rotor is driven directly by gears, optimizing their linear speed and significantly enhancing compression efficiency.
8) Internal Spray Curtain Cooling Method:Employing a high energy-saving internal spray curtain cooling method, this design delivers excellent cooling performance. It significantly reduces the temperature of compressed air, approximating isothermal compression, and minimizes pressure loss between stages, thus improving compression efficiency.
9) Minimized Internal Leakage:The two-stage compression design lowers the compression ratio for each stage, reducing internal leakage from high-pressure to low-pressure ends and enhancing volumetric efficiency.
10) Noise Reduction:The two-stage compression process decreases the overall compression ratio, substantially reducing noise levels, particularly during unloading.
11) Simplified Maintenance and Service:Aside from the screw air end, the two-stage compressor unit shares similar systems and structures with single-stage units, making maintenance and user handling straightforward and convenient.
1. Exceptional Price Advantage
We offer ex-factory prices directly to our customers, ensuring you stay ahead in the competitive market.
2. Seamless Direct Deal
All our products come straight from the factory, guaranteeing you more cost-effective solutions.
3. Comprehensive OEM & ODM Services
Our robust production and management capabilities enable us to deliver top-notch OEM/ODM services tailored to your needs.
4. Tailor-Made Customised Service
We accommodate non-standard orders, export requirements, and specific voltage/power/pressure needs. Reach out to us for any custom demands.
5. Flexible Small Order Acceptance
Experience our product quality with a small trial order before making larger commitments.
6. Rapid Delivery
Benefit from high-quality products delivered promptly, every time.
7. Full Authorization Support
For our valued distributors, we provide complete authorization certificates, empowering you to sell SANZHI brand products with confidence.
Sanzhi (Henan) Compressor Co., Ltd, a leading manufacturer with over a decade of experience, specializes in screw air compressors and screw vacuum pumps. Our diverse product portfolio includes: normal pressure/low-pressure screw air compressors, permanent magnet frequency conversion screw air compressors, two-stage compression screw air compressors, screw air compressors for laser cutting, single-tank mobile screw air compressors, double-tank mobile screw air compressors, electric mobile screw air compressors, diesel mobile screw air compressors, and screw vacuum pumps.
Our production lines, featuring state-of-the-art, multi-air compressor assembly systems, ensure maximum efficiency. With a dedicated team of over 50 employees, we continuously refine our management systems, such as ERP, to reduce lead time and deliver superior products swiftly.
Our commitment to quality is evidenced by our ISO9001 certification. We strictly adhere to rigorous quality management protocols, ensuring every machine undergoes meticulous material, production, and pre-delivery inspections before it reaches our customers.
For pre-sales support, we provide expert guidance in selecting the optimal air equipment, offering high customization options, including appearance and configuration. We also cater to OEM demands, crafting unique products for dealers. Our dedicated sales and service team ensures prompt and responsive after-sales support.
At Sanzhi (Henan) Compressor Co., Ltd, we are committed to delivering superior, stable products, fostering long-term relationships with our clients. Our hallmarks are efficient delivery, high-quality machines, and exceptional value, making us your trusted partner for compressed air solutions.
Our factory is conveniently located in Xinzheng City, Henan Province, China. We offer complimentary pickup from Xinzheng International Airport, just 30 kilometers away, about a one-hour journey. We warmly welcome you to visit our company!
FAQ
Q1. Are you a trading company or manufacturer?
A: We are a professional manufacturer of screw air compressors, with more than 10 years of experience.
Q2. How do you control quality?
A: 1. The raw materials are strictly inspected.
2. Installation procedures are strictly controlled.
3. Each machine must pass at least 5 hours of continuous testing before leaving the factory.
Q3. What information must I provide to get the suitable machine?
1. How much air delivery capacity (Unit: CFM or m³/Min)
2. How much working pressure (Unit: PSI, Bar or Mpa)
3. What is the voltage and frequency of my country of residence (V/Hz)
4. Whether I need other accessories such as an air tank, filters, and/or air dryers.
Tell us the answer, we will offer a scheme for you!
Q4. What is the general unit conversion?
1Bar = 0.1Mpa = 14.5PSI
1m³/min = 35.32cfm
1KW = 1.34HP
Q5. What is the available voltage air compressor?
A: Sanzhi available voltage include 380v/50hz/3p, 400v/50hz/3p, 415v/50hz/3p, 220v/60hz/3p, 440v/60hz/3p, and can be customized according to your requirements.
Q6. How long is the delivery time?
A: For standard voltage,15 working days after the confirmed order. Non-standard, please contact our sales.
Q7. What's the payment term?
A: 30% T/T in advance, 40% T/T before shipment, and 30% T/T against the B/L copy. USD, RMB can be accepted.
Q8. How about your warranty?
A: One year for the whole machine and two years for screw air compressor, except for consumable spare parts.
Q9. What about the maintenance?
A: First maintenance needs to be done after 500 hours, and then every 2000-3000 hours to do the normal maintenance, and consider the actual environment.
Q10. Can machines be run in high-temperature environment?
A: Yes, machines would run in high-temperature environment countries. Working temperature from -20° to 45°(-4ºF-113ºF).
Q11. Do you offer OEM service?
A: Yes, with a professional design team, both OEM & ODM orders are highly welcome.
Q12. How long could your air compressor be used?
A: Generally, more than 10 years.
Q13. Will you provide some spare parts for the machines?
A: Yes, of course.
Q14. How about your after-sales service?
A: Provide customers with installation and commissioning online instructions, and arrange for our engineers to help you with training and installation.
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