Internal Structure Frontside
Internal Structure Backside
Working Principle
Under optimal air compression conditions, the energy required for single-stage pressure transmission is theoretically equal to the sum of energies for multi-stage compression. However, real-world scenarios introduce variables like coupling transmission losses, bearing friction, and the cooling effect of viscosity, which elevate the actual operational power. By reducing the compression ratio at each stage, we can significantly diminish total power consumption in multi-stage compression, rendering it more energy-efficient compared to single-stage compression.
The two-stage screw air compressor is engineered with a dual-stage rotary screw configuration, consisting of both an active and passive screw in each stage. The active screw drives the passive screw via an external power source. The initial stage features a low-pressure rate screw group, while the second stage is equipped with a high-pressure rate screw group. Each screw is enveloped by a sealing air film. As the screws rotate, the air undergoes three critical processes: suction, pressurization, and exhaust.
First Stage Compression: In the initial stage, the two-stage screw air compressor employs a low-pressure screw group to compress the gas. The gas is drawn into the compression chamber through the suction valve. With the rapid rotation of the screw rotor, the gas is incrementally compressed and then conveyed to the next stage.
Second Stage Compression: At this stage, the gas is introduced into a more confined screw space, resulting in elevated temperatures and pressures. The exhaust valve then opens, allowing the high-pressure gases to be expelled from the system.
Natural air is initially drawn into the first compression stage via an air filter, where it combines with a small quantity of lubricating oil. This mixture is compressed to an intermediate pressure. The compressed gas then traverses a cooling channel, encountering substantial oil mist that markedly reduces its temperature. This cooled gas proceeds to the second-stage rotor for further compression, achieving the final exhaust pressure. Finally, the compressor expels the gas through the exhaust valve, completing the comprehensive compression cycle.
| Sanzhi (Henan) Compressor Co,. Ltd. |
| Two-Stage Compression Permanent Magnet Variable Frequency Screw Air Compressor |
| Model |
Power |
Exhaust pressure |
Free air delivery* of unit at working pressure |
Voltage |
Frequency |
Air outlet discharge size |
Weight |
Dimensions |
| KW |
Mpa |
m³/min |
V |
Hz |
Inch |
Kg |
L*W*H(mm) |
| SZ15VF-II |
15 |
0.5 |
4.00 |
380 |
50 |
G1½ |
660 |
1450*780*1180 |
| 0.8 |
3.00 |
| 1.3 |
2.00 |
| SZ19VF-II |
18.5 |
0.5 |
5.00 |
380 |
50 |
G1½ |
680 |
1450*780*1180 |
| 0.8 |
4.00 |
| 1.3 |
3.80 |
| 1.6 |
2.20 |
| SZ22VF-II |
22 |
0.5 |
6.60 |
380 |
50 |
G1½ |
730 |
1650*880*1280 |
| 0.8 |
4.20 |
| 1.3 |
3.00 |
| 1.6 |
2.50 |
| SZ30VF-II |
30 |
0.5 |
7.00 |
380 |
50 |
G1½ |
980 |
2000*1260*1560 |
| 0.8 |
6.40 |
| 1.3 |
4.00 |
| 1.6 |
3.00 |
| SZ37VF-II |
37 |
0.5 |
10.00 |
380 |
50 |
G1½ |
1080 |
2000*1260*1560 |
| 0.8 |
7.00 |
| 1.3 |
5.50 |
| 1.6 |
4.00 |
| SZ45VF-II |
45 |
0.5 |
13.00 |
380 |
50 |
G2 |
1980 |
2000*1260*1560 |
| 0.8 |
10.00 |
| 1.3 |
6.50 |
| 1.6 |
5.00 |
| SZ55VF-II |
55 |
0.5 |
17.00 |
380 |
50 |
G2 |
2180 |
2150*1300*1730 |
| 0.8 |
12.00 |
| 1.3 |
8.60 |
| 1.6 |
5.00 |
| SZ75VF-II |
75 |
0.5 |
20.00 |
380 |
50 |
G2 |
2280 |
2150*1300*1730 |
| 0.8 |
16.50 |
| 1.3 |
11.00 |
| 1.6 |
9.00 |
| SZ90VF-II |
90 |
0.5 |
24.00 |
380 |
50 |
DN65 |
3200 |
2700*1920*1820 |
| 0.8 |
20.00 |
| 1.3 |
14.00 |
| 1.6 |
11.00 |
| SZ110VF-II |
110 |
0.5 |
28.00 |
380 |
50 |
DN65 |
3360 |
2700*1920*1820 |
| 0.8 |
24.50 |
| 1.3 |
18.00 |
| 1.6 |
14.00 |
| Due to product updates, the above parameters are subject to deviation in kind. |
1) Unparalleled Efficiency of PM Motor:Experience unprecedented efficiency with our advanced PM motor. The extended constant torque and weak magnetic ranges outperform conventional motors by 20-30%. Even outside the rated frequency, the PM motor consistently delivers exceptional efficiency, ensuring superior performance at all times.
2) Maintenance-Free Motor:Our innovative permanent magnet motor is engineered without bearings, completely eliminating the need for costly bearing maintenance and replacements.
3) Advanced Integrated Frequency Converter:Equipped with China's premier frequency system, this unit offers extensive speed regulation with high precision. It adapts perfectly to actual gas demand, delivering remarkable energy-saving results.
4) Zero Transmission Loss:The direct drive connection between the permanent magnet motor and compressor features a compact, integrated shaft, eliminating couplings and other transmission components for 100% transmission efficiency.
5) Variable and Soft Start MechanismsOur variable frequency and soft start mechanisms minimize impact on power grid equipment, effectively preventing electrical component damage.
6) Enhanced Energy Conservation:With a frequency conversion range spanning 25% to 100% (compared to the standard 50%-100%), this unit achieves over 30% energy savings against fixed-speed compressors. Systems with variable gas demand benefit even more from this energy efficiency.
7) Unique Two-Stage Compression Air End:Our specialized two-stage compression screw design integrates first and second-stage rotors within a single casing. Driven by gears, each stage achieves optimal linear speeds, significantly boosting compression efficiency.
8) Innovative Internal Spray Curtain Cooling:Our high-energy saving internal spray curtain cooling method dramatically lowers compressed air temperature, achieving nearly isothermal compression. This method reduces pressure loss and enhances overall compression efficiency.
9) Minimized Internal Leakage:By implementing two-stage compression, we reduce the compression ratio for each stage, thereby minimizing internal leakage and improving volumetric efficiency.
10) Superior Noise Reduction:Two-stage compression not only cuts the compression ratio but also significantly lowers noise levels, especially during unloading.
11) Effortless Maintenance and Service:Aside from the screw air end, the systems and structures of the two-stage compressor are similar to single-stage compression units, ensuring convenient maintenance and ease of use for operators.
1. Unbeatable Price Advantage
We offer customers competitive ex-factory prices directly, ensuring you stay ahead of the market.
2. Direct Transactions
All our products are supplied straight from the factory, enabling us to offer you more cost-effective options.
3. Comprehensive OEM & ODM Services
With our robust production and management capabilities, we can cater to your OEM/ODM service needs seamlessly.
4. Tailored Customization
We welcome non-standard, export, voltage/power/pressure custom orders. Contact us to discuss your specific requirements and we will fulfill your demands.
5. Small Order Acceptance
Start with a small trial order to evaluate the premium quality of our products.
6. Rapid Delivery
We promise timely delivery of our high-quality products, ensuring your operations run smoothly.
7. Comprehensive Authorization
For distributors, we provide full authorization certification, empowering you to sell our prestigious SANZHI brand products.
Sanzhi (Henan) Compressor Co., Ltd. is a distinguished manufacturer with a rich legacy of over a decade in producing high-performance screw air compressors and screw vacuum pumps. Our diverse product range comprises cutting-edge normal and low-pressure screw air compressors, energy-efficient permanent magnet frequency conversion screw air compressors, robust two-stage compression screw air compressors, specialized screw air compressors for laser cutting, versatile single-tank and double-tank mobile screw air compressors, both electric and diesel-powered mobile models, and high-efficiency screw vacuum pumps, among others.
At our ultra-modern production facility, our advanced, lean multi-air compressor assembly lines ensure remarkable efficiency. With the dedication of over 50 skilled employees, we continually optimize our management systems, including ERP, to significantly reduce lead times and guarantee the swift delivery of top-quality products.
Our unwavering commitment to quality management has earned our factory ISO9001 certification. We rigorously enforce stringent quality protocols, ensuring every machine undergoes meticulous inspections, from material checks to production evaluations and pre-delivery assessments.
We pride ourselves on exceptional customer service that spans from pre-sales to after-sales. Before purchase, we offer expert advice to help you select the ideal air equipment and provide extensive customization options, including bespoke OEM products tailored to specific dealer requirements. Post-purchase, our professional sales and service team is always prepared to respond promptly to customer needs.
At Sanzhi (Henan) Compressor Co., Ltd., we are committed to delivering superior, reliable products and cultivating long-term customer relationships. With our unwavering dedication to efficient delivery, exceptional quality, and competitive pricing, we are your trusted partner for optimal compressed air solutions.
Our factory is ideally situated in Xinzheng City, Henan Province, China. We offer complimentary transportation from Xinzheng International Airport to our facility, conveniently located just 30 kilometers away, approximately a one-hour journey. We look forward to your visit and the opportunity to showcase our company!
FAQ
Q1. Are you a trading company or manufacturer?
A: We are a professional manufacturer of screw air compressors, boasting over 10 years of specialized industry experience.
Q2. How do you control quality?
A: 1. We rigorously inspect all raw materials.
2. We maintain strict oversight of installation procedures.
3. Each machine undergoes a minimum of 5 hours of continuous testing before dispatch to ensure top performance.
Q3. What information must I provide to get the suitable machine?
1. Desired air delivery capacity (Unit: CFM or m³/Min)
2. Required working pressure (Unit: PSI, Bar, or Mpa)
3. Voltage and frequency in your country (V/Hz)
4. Additional accessories needed, such as air tanks, filters, or air dryers.
Provide us with this information, and we will customize a solution tailored just for you!
Q4. What is the general unit conversion?
1Bar = 0.1Mpa = 14.5PSI
1m³/min = 35.32cfm
1KW = 1.34HP
Q5. What are the available voltage options for air compressors?
A: Sanzhi air compressors are available in voltage options of 380v/50hz/3p, 400v/50hz/3p, 415v/50hz/3p, 220v/60hz/3p, and 440v/60hz/3p. We also offer further customization to meet your specific needs.
Q6. How long is the delivery time?
A: For standard voltage, our delivery time is an impressive 15 working days post-confirmation of your order. For unique or non-standard requirements, please reach out to our dedicated sales team for personalized assistance.
Q7. What's the payment term?
A: We accept a flexible payment structure: 30% T/T in advance, 40% T/T before shipment, and the final 30% T/T upon receipt of the B/L copy. Payments can be comfortably made in either USD or RMB.
Q8. How about your warranty?
A: We provide a comprehensive one-year warranty for the entire machine, with an extended two-year warranty specifically for the screw air compressor, excluding consumable spare parts.
Q9. What about the maintenance?
A: The initial maintenance should be conducted after 500 hours of operation. Thereafter, regular maintenance should be performed every 2000-3000 hours, tailored to the actual working environment.
Q10. Can machines be run in high-temperature environment?
A: Absolutely, our machines are meticulously engineered to operate efficiently in high-temperature environments, with a working temperature range from -20° to 45° (-4ºF to 113ºF).
Q11. Do you offer OEM service?
A: Yes, we proudly offer OEM & ODM services. With our expert design team at your disposal, customized orders are highly welcomed and can be tailored to your specific needs.
Q12. How long could your air compressor be used?
A: Our air compressors are constructed for exceptional durability and can generally be relied upon for more than 10 years.
Q13. Will you provide some spare parts for the machines?
A: Certainly, we provide essential spare parts to ensure the uninterrupted and seamless operation of your machines.
Q14. How about your after-sales service?
A: We offer comprehensive after-sales support, including detailed online installation and commissioning instructions. Additionally, we can arrange for our skilled engineers to assist with on-site training and installation.
Audited Supplier 
){kind=link}
){kind=link}