Low-Pressure Compressor Two-Stage Compression Permanent Magnet Variable Frequency Drive Screw Air Compressor for Industry, 15KW, 22KW, 30KW, 37KW, 45KW, 55KW, 75KW, 90KW, 110KW, 132KW, 160KW, 185KW, 200KW, 250KW
Internal Structure Frontside
Internal Structure Backside
Working Principle
In an ideal air compression process, the power required for single-stage pressure transmission is equal to the sum of the power required for multi-stage compression. However, in the actual compression process, the actual working power will become larger due to the transmission power loss of the coupling, the friction coefficient of the bearing and the cooling effect of liquid viscosity and other factors. Therefore, useless power can be reduced by reducing the compression ratio of each stage, so that the total power required for multi-stage compression is less than that required for single-stage compression.
The two-stage screw air compressor is composed of a two-stage rotary screw compressor. Each stage has an active screw and a passive screw. The active screw drives the passive screw to rotate through an external power transmission device. The first stage of the two-stage screw air compressor uses a low-pressure rate screw group, and the second stage uses a high-pressure rate screw group. There is a sealing air film around each screw. While rotating, the gas is compressed through three processes: suction, pressurization, and exhaust.
First stage compression: The first stage of the two-stage screw air compressor uses a low-pressure rate screw group, and the gas is squeezed between them. The gas enters the screw compression chamber through the suction valve. Under the high-speed rotation of the screw rotor, the gas is gradually squeezed out and transferred to the second stage.
Second stage compression: In the second stage screw group, the gas enters a tighter screw space and is squeezed at higher temperature and pressure. The exhaust valve will open, removing high-pressure gases from the system.
Natural air enters the first stage of compression through the air filter, mixes with a small amount of lubricating oil in the compression chamber, and simultaneously compresses the mixed gas to the interstage pressure. The compressed gas enters the cooling channel and comes into contact with a large amount of oil mist, thereby greatly reducing the temperature. The cooled compressed gas enters the second-stage rotor, undergoes two-stage compression, and is compressed to the final exhaust pressure. Finally, the compressor is discharged through the exhaust valve to complete the entire compression process.
1) High efficiency of PM motor: The constant torque range and weak magnetic range are wider, The efficiency of the permanent magnet motor is higher by 20-30% than that of the regular motor. When the permanent magnet motor operates away from the rated frequency, its efficiency is basically unchanged, and it can still maintain extremely high motor efficiency.
2)Two-stage compression unique air end: The two-stage compression screw machine has a unique design for the air end. It combines the first-stage compression rotor and the second-stage compression rotor in a case, and rotates them directly through gears respectively, so that each stage of the rotor can obtain the best linear speed, so that the compression efficiency is higher.
3)Integrated frequency converter: Adopt the top frequency system in China, with a wide range of speed regulation, and high precision, according to the user's actual gas demand frequency modulation operation, the air compressor energy saving effect is remarkable.
4)Reduce internal leakage: Two-stage compression is adopted, which reduces the compression ratio of each compression, reduces the internal leakage from the high-pressure end to the low-pressure end, and improves the volume efficiency.
5)Variable frequency start and the soft start of the motor are realized, which greatly reduce the impact on the power grid equipment and do not cause damage to the electrical equipment.
6)Reduce energy consumption: Frequency conversion range from 25% to 100% (ordinary frequency conversion from 50% to 100%), compared with fixed speed air compressor, energy saving up to more than 30%; Compared with the ordinary variable frequency air compressor, the energy saving is about 5%. And the larger the fluctuation of the system gas consumption, the more obvious the energy-saving effect.
7)No transmission loss: the permanent magnet motor and the compressor adopt the embedded integrated shaft directly connected structure, which is more compact in structure. There is no coupling and other transmission parts, and the transmission efficiency is 100%.
8)Air cooling method: using high energy saving air cooling method, good cooling effect, greatly reduces the temperature of compressed air, achieves close to isothermal compression, but also can reduce the pressure loss between the first and second, reduce the compression ratio, improve the compression efficiency.
9)Smart Touch Controller: Superior built-in intelligence requires minimal manual operation. A high-precision color electronic screen, clear graphics display, and indication of maintenance information, fault alarms, and safety shutdown alarms.
10)Special Type Intake Valve: Automatic control of the opening, to ensure the engine fuel injection and lubricating oil circulation.
Ultra-low oil circuit loss, overall efficiency improvement.
Normally open solenoid valve control, emergency stop automatically closed, prevent oil injection.
11)Excellent Air Filter: An air filter with excellent air purification capability ensures a clean air system and three-stage filtration to maximize air purification and meet standard emissions, it can remove a lot of steam and a small amount of dust gas occasions.
12)High-Quality Soundproof Cotton: Compact noise reduction housing, achieving no vibration amplitude during operation, cooperates with high-quality soundproof cotton to further improve noise reduction levels.
13)Motor maintenance-free: The permanent magnet motor has no bearings inside, which eliminates the cost of motor bearing maintenance and replacement.
14)Noise reduction: Two-stage compression reduces the compression ratio and greatly reduces the noise, especially the unloading noise.
15)Easy to do maintenance and service: Two-stage compressor unit, except the screw air end, other systems and structures of the unit are basically the same as single-stage compression, which brings convenience to the maintenance and use of users.
| 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. |
Direct to provide customers with ex-factory prices, so that customers are more competitive.
2. Direct deal
All products are supplied directly from the factory and we will offer more cost-effective products.
3. OEM & ODM services
The strong production and management capacity of the factory can provide OEM/ODM service for you.
4. Customised service
We accept non-standard orders, export orders, voltage/power/pressure, etc, which can be customized. If you have demands, please contact us.
5. Accept small order
You can place a small trial order first to test the quality of our products.
6. Fast delivery
High-quality products with timely delivery.
7. Complete authorisation
For distributors, we can provide the full authorization certificate to allow you to sell our SANZHI brand products.
Sanzhi (Henan) Compressor Co., Ltd is a manufacturer in the production of screw air compressors and screw vacuum pumps, with more than 10 years of experience. The extensive product range 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 compressor, electric mobile screw air compressor, diesel mobile screw air compressor, screw vacuum pump, etc.
In production, we are able to achieve the most efficient production by multi-air compressor assembly lines which are lean and modern. With the effort of over 50 employees, we continue to optimize management systems such as ERP to shorten the lead time and deliver qualified products at a fast speed.
In management, our factory passed ISO9001 quality management system certification. We always adhere to the implementation of the stringent quality management system, and strictly implement the standard quality control processes. The outgoing of each machine is an experience of material inspection, production inspection and pre-delivery inspection.
In customer service, on the hand of pre-sales, we offer our customers a professional guide to choosing air equipment for multiple facilities and supply with high customization like its appearance and allocation, and we are even able to create unique products to meet dealer's demand, that is OEM. Meanwhile, for after-sales, we staffed a professional sales & service team for quick response to customers.
We Sanzhi (Henan) Compressor Co., Ltd, devote ourselves to delivering superior and stable products, for building long-term relationships with our customers. Efficient delivery, qualified machine, and worthy price, we are reliable to provide you with a satisfactory compressed air solution.
Our factory is located in Xinzheng City, Henan Province, China. We can pick you up from Xinzheng International Airport to our factory, 30 kilometers in about one hour. Welcome to 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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