Distributor / authorized representative that deals with supply & delivery of screw compressors to industrial enterprises of Russia
Engineering company ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), Russia, has been successfully working with a number of Russian industrial enterprises at the local market for more than 20 years. Since the company’s founding, it has acquired immense engineering experience, market reputation, and has realized more than a hundred large-scale projects at the industrial plants in Russia. Our company is continuously in search of new business partners, who consider Russian market investment-attractive and want to boost their sales in the region, as well as expand their field of activities and enter a new international level.Contents:
We are interested in cooperation with the manufacturers of screw compressors (screw compressor lines), who are looking for an official and reliable distributor to supply their equipment to the industrial plants in Russia.
The company’s top management and sales team are well acquainted with the Russian market, its mentality and laws; they also understand industrial specifics of the financial and economic activities of the Russian customers. All our sales managers have a large customer database, extensive experience of successful sales and well-established connections with the potential buyers of your screw compressors. This allows our managers to promptly set out the most promising directions for promotion and to ensure a rapid entry of the products into the promising Russian market. Our employees, who are fluent in English and German, are focused on working at the international market with the supplies of foreign equipment.
Our team of experienced engineers, who can handle the most serious technical problems, constantly keeps in touch with the Russian customers, holds meetings and delivers presentations regarding the latest achievements of our manufacturing partners. They point out the engineering challenges and actively communicate with all the departments at Russian plants. That is why the specifics of doing a business in the Russian Federation are well-known to us, and we also know the equipment of the local industrial plants and their up-to-date modernization needs.
Once we become your authorized representative for screw compressor lines in Russia, our marketing staff will carry out a market research in order to check the demand for screw compressor lines, will submit a market overview for screw compressors that you offer and evaluate the needs for this type of equipment at local plants. Our specialists will also estimate the potential and capacity of this market at local industrial plants. Our IT-team will start developing a website for your products in Russian. Our experts will assess the conformity between your screw compressor lines and customer needs as well as analyze the common reaction to the new goods in general. We will look into the categories of potential customers, and pick out the largest and the most promising plants.
Upon becoming your authorized agent on the territory of Russia, ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), will obtain certificates, if required, for a batch of the goods or for various types of screw compressors (screw compressor lines) in compliance with Russian standards. We can also arrange the inspection in order to obtain TR TS 010 and TR TS 012 Certificates. These certificates provides permission to operate your equipment at all industrial plants of the EAEU countries (Russia, Kazakhstan, Belarus, Armenia, Kyrgyzstan), including the hazardous industrial facilities. Our company is eager to assist in issuing Technical Passports for screw compressors as per Russian and other EAEU countries’ requirements.
Our engineering company ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), collaborates with several Russian design institutes in various industrial segments, which allows us to conduct preliminary design as well as subsequent design works according to the standards, construction rules and regulations that are applicable in Russia and other CIS countries. It also enables us to include your screw compressor lines into the future projects.
The Company has its own logistics department that can provide packing service, handling as well as the most efficient and cost effective mode of transportation of the goods (incl. over dimensional and overweight goods). The goods can be delivered on DAP or DDP-customer’s warehouse basis in full compliance with all the relevant regulations and requirements that are applicable on the Russian market.
Our company has its own certified specialists who will carry out installation supervision and commissioning of the delivered equipment, as well as further guarantee and post-guarantee maintenance of screw compressors. They will also provide necessary training and guidance for the customer’s personnel.
Description of screw compressors
The screw compressor is a machine for industrial use, forcing air by means of the screw pair. This type of equipment is widely used in industry when it is necessary to supply continuously compressed air to pneumatic systems. Screw compressors are cost efficient and modern devices characterized by moderate consumption of electric power, easy maintenance and control, as well as durability.
The screw compressor unit is equipped with air, liquid, or oil cooling system. As a result of the refrigeration procedure, the air may contain oil droplets, solid particles and water vapor, which contributes to wear of the equipment. Therefore, air and liquid cooling systems are used in industries where it is necessary to maintain high standards of compressed air purity. There are also models of compressors equipped with the receiver and the dryer, which, along with cleansing impurities from the air, ensure its uniform supply and energy savings. Such models are a good solution for compact productions.
Screw compressor units are activated by an electric motor. Movement of a certain volume of coolant (refrigerant) in the form of gas allows to precisely monitor the cooling process in the compressor. The compressor is equipped with the spool that reduces the level of gas inflow and power.
The screw compressor is able to operate at idle, which reduces power consumption up to five times, as well as minimizes wear of the parts due to lack of unnecessary switching of the electric motor.
This type of compressor, unlike reciprocating compressor units, does not emit excess air. Furthermore, the screw compressor produces compressed air of moderate temperature, since the final compressor delivery temperature is low.
For the first time, screw-type compressors were patented in the 1930s. Due to the fact that they were a worthy competitor to other types of positive displacement compressor systems, their popularity and application became wider. Nowadays screw compressors actively function in various areas of production. Their technical characteristics are comparable to those of reciprocating units of industrial grade and are relevant for enterprises that need to maintain a continuous production process.
Operation principle of screw compressors
Screw compressor units are equipped with two screws, one of which has the concave surface, and the second - the convex one.
The screws and the housing of the compressor together form the working chamber volume. The chamber size increases as the screws rotate, and the suction is carried out as the projections on the rotors move away from the concaves. At the maximum volume of the chamber, the suction process is terminated. The chambers end up in an isolated position in relation to the pipes. Next, the projection of the male rotor enters the concave of the female rotor (penetration takes place from the outset of the rotor and up to the discharge opening). At some point, the two surfaces form a common volume that is gradually decreasing because of elements moving towards the discharge opening. The gas is displaced.
In the typical design of the screw compressor, unit oil is not supplied to the working area. The screws are located inside the housing equipped with connectors (one or more), bores, seals and chambers (suction and discharge). These systems use bearings (axial and pedestal) due to high frequency of rotational movements made by the screw pair.
Release of oil from the bearing units into the compressed gas and the bearing chambers is prevented by using barrier gas. It is supplied to the seal assemblies that are represented by a group of rings between the screws and the bearing chambers.
Schematic drawing of a standard screw compressor.
In the simplest and most common arrangement, the air passes through the suction valve and the air filter (1) with contamination sensors and enters the screw pair (2). The screw pair (2) where the air is mixed with pre-cleaned oil represents the "heart" of the compressor. The air-oil mixture formed after that is supplied to the pneumatic system by means of the air end. The compressor is equipped with a separator where oil and air are separated. The air separated from the oil enters the compressor outlet part after passing through the cooling radiator device (9). And the oil flows back to the screw pair. The further flow of the oil is determined by the temperature: either it moves in the small circle or, if it needs to be cooled, it goes through the radiator in the large circle. The temperature is determined by the thermostat (7) controlling the oil during its passage through the radiator (8). The oil remaining in the separator is supplied to the screw mechanism through the pipe (10). The electric motor drives the screw pair. The compressor turns on and off automatically by means of the controller or the pressure switch. The following scheme allows to clearly tracing the above-described arrangement of a standard screw compressor.
Main components and design features of screw compressors
Screw compressor units are equipped with the screw pair (two rotors with blades). One of the screws has the concave surface; the surface of the second one is convex. As the screws make multidirectional rotational movements, the gas is compressed. Compression is carried out up to the limit moment, after which some volume is displaced through the discharge opening of the end wall.
Classical modification of such compressor is equipped with two screws. There are also single-screw models, which employ one bearing screw, and an electric motor as the drive.
The main elements of the design of this type of machines are the compressor housing, electric motor, fan, unit (where the screws are located), filters (oil and suction), devices for cooling and oil separation, end air cooler, control and monitoring system, pipes (air and oil). Supporting elements are pressure switch, thermostat, safety valve, etc.
The screw compressor similar to the reciprocating unit can be equipped with a receiver (or air collector), which helps to stabilize the mode of operation, improve the quality and cool the compressed air. An adjustable drive generally improves the overall efficiency of compressor systems. Electronic control systems based on the latest microprocessors can control the key operating parameters.
Types of screw compressor units
The classic model of this type of compressors is equipped with two screws (with the convex and concave surfaces). However, there are two types of screw compressor units: single-screw and double-screw compressors. In the classic version, the screw pair makes multidirectional rotational movements, resulting in gas compression. The single-screw unit has one bearing screw that is driven by an electric motor.
Compressor units can be divided in types according to the drive type: belt-driven and direct-drive units.
The belt-driven compressors have two pulleys (one directly on the motor, the second on the screw pair) causing the rotors to rotate. The higher the speed of the rotational movements, the higher levels of performance, but the lower the operating pressure. The direct-drive compressors use the gearbox or the direct drive through the coupling.
Depending on the fillability of the oil tank, where the compressor screws rotate, and the actual compression takes place, with oil, units are divided into:
Oil-flooded screw compressors
Widely applicable type of compressors. Only one screw is usually engaging. The female rotor rotates after the male one. The oil is involved in dissipation of heat formed in the compression process. The separator, giving the clean compressed air at the outlet, subsequently removes the oil. Although 99.9% of the oil remains in the compressor, there is always a bit of oil, which penetrates the separator and leaves the compressor in the compressed air, the so-called oil carry over. Therefore, these compressors cannot be used where there is need for oil-free compressed air.
However, for the majority of factories, shops and machine industry insignificant content of oil is not critical. In fact, it prevents rust formation (within the air compression system) and helps the machine run smoothly.
- quiet operation
- high air flow, uniform flow
- suitable for continuous operation
- expensive compared to the reciprocating compressor type
- not suitable for long-term downtime
- oil carry over
Oil-free screw compressors
The basic operation principle is the same as that of oil-flooded compressors, but in this case the oil is not used, only air! Since there is no oil injected during the compression, the compression is usually carried out in two stages. If we compress the air in one stage, for example from 1 to 7 bar, it will become very hot.
Stage 1 compresses the air to a few bars (e.g. 2.5bar). The air here is very hot, so it is first supplied through the intercooler before being passed to the second stage. Stage 2 compresses the air from 2.5bar further to the desired value, for example up to 7bar.
Typically, 2 stages are built in 1 gearbox with 1 electric motor which sets them in motion simultaneously.
If you need 100% oil-free air in large quantities, the oil-free screw compressor is your choice. Of course, here we also talk about the high price, but if you really need 100% oil-free air, then this is the only option.
- 100% oil-free air
- More expensive than the oil-flooded type.
- Maintenance/repair is more complicated and more expensive than that of the oil-flooded compressor.
- More noisy than the oil-flooded type.
Oil-free compressors have many fields of application. These are food and chemical industries, pharmaceutics, electronics and semiconductor manufacturing. Screw oil-free compressors can be subdivided into oil-free compressors with water injection into the compression chamber and dry screw compressors.
Water-filled screw compressors
Screw compressors with water injection are the only compressors with a capacity of less than 55kW that reach 13bar. Regardless of the final compression level, with the dosed injection temperature does not rise by more than 12°. The thermal load on the device elements is insignificant, which increases the service life, reliability and safety of the unit as a whole. With this technology, excellent cooling ability of water provides efficient heat transfer to the source.
Screw compressors with injected fluid typically do not require that two counter-rotating rotors be in proper engagement. Water is the layer that separates 2 screw profiles even if one rotor "sets in motion" the other. This type of compressors can be very beneficial to the consumer, as it provides the following advantages:
- the injected fluid provides internal cooling. Some gases in this case are not polymerized and do not work in hazardous temperatures.
- Water-filled screw compressors achieve a much greater degree of compression.
Typical applications for water-filled screw compressors: recirculation gases, ethylene oxide, carbon dioxide and very specific gases, such as chlorine gas.
Any types of compressors or compressor devices are used to compress and further supply the air or gas medium compressed under pressure. Screw compressors, or, as they are also called, screw air compressors are a subtype of rotary compressor devices. Here the compression of the medium is carried out through the rotation of two rotors. The rotors are engaged and equipped with helical teeth.
Screw-type compressors, as mentioned above, belong to the class of displacement rotary compressor units, where the compression of the medium takes place with the reduction of the enclosed volume. The compressed air supplied from the compressor can be used as energy for the actuators as well as for the implementation of all kinds of processes using compressed air.
The modern industry needs productive and economic equipment of high quality, in particular, compressors, and this demand is constantly growing.
Screw compressors with single and double screw
Many different types of screw compressor devices are produced today. They should be divided into two groups:
- with single screw and
- with double screw.
The design of the single-screw compressor involves the use of the central rotor, which acts as a screw. Each side of the rotor has two or one gear. The central screw causes the rotation of the rotors carrying out the compression of gases and air entering the inlet of the compressor.
The operation principle of the single-screw compressor
The double-screw compressor is equipped with two rotors: operating and driving, or main and auxiliary. Screw type compressors have no valves at the inlet and outlet. A medium, for example, refrigerant, is sucked into the compressor on one side, and leaves from the other side. Rotating in opposite directions, the rotor compresses the gaseous refrigerant. The rotation of the operating rotors is driven by the rotation of the central driving rotor, which is designed in the form of a screw. Hence, the name: "screw" compressors.
Refrigerant vapor, entering the inlet of the screw-type compressor unit, cools the electric driving motor, and then passes through special channels in the cavity of the outer zone. Here are located the rotor gears compressing these channels. The outlet, equipped with a valve, releases the refrigerant from compressor unit.
In this type of compressors the compression of media, air, other gases or refrigerant follows the same principle as in the first case.
The operation principle of the double-screw compressor
Differences in screw compressors due to the drive type
The design of screw compressors provides for the use of 4 types of drives: belt-drive, gear drive, direct drive and direct frequency-regulated drive.
Differences in screw compressors due to the drive type
- The belt-driven screw compressor is relatively easy to operate. This is a huge advantageous factor, as there is no need to engage highly qualified personnel for its technical inspection. The plant usually maintains this type of compressors. Another advantage of this category of compressors is the ability to adjust it. The number of revolutions of the compressor unit screw is not connected with the engine speed; there occur variations in the gear ratio. One should also note the disadvantages found in this type of compressors:
- relatively low efficiency, which directly depends on the belt wear;
- loud noise in comparison with other types of screw compressor units;
- belt quick wear due to dust presence in the air.
- The gear-driven screw compressor units are characterized by low noise and smooth running of the drive. They have a very high efficiency factor (98% or higher). The high performance level makes it possible to use this type of compressor equipment in difficult conditions, for example, in industries with high levels of dust formation, such as cement packing or flour grinding. The disadvantages of this type of equipment include such things as absence of adjustment, expensive repairs, since they require qualified experts. They are not always available on site, and the engagement of outside organizations brings about extra costs.
The gear-driven screw compressor is suitable for industries with difficult operating conditions. They can be installed both in small workshops and in large factories using compressed air.
- The direct-drive screw compressor equipment is characterized by an extremely high efficiency factor (99.9%). It does not react to dust particles or other contaminants caught into the mechanism, and is not susceptible to overloaded operating conditions. The smooth running of the drive in the screw compressor is the result of a long engine life. The service life of the compressor device itself can amount to decades without major overhaul. As with any type of compressors, the direct-drive screw compressor has negative aspects, too, such as absence of adjustment (since the engine speed is the same as the speed of the air end). Maximum operating pressure in the compressor cannot be changed.
The direct-drive screw compressor is suitable for industries with difficult operating conditions. It can be installed both in small workshops and in large factories using compressed air, but not in factories where it is necessary to change maximum working pressure of the compressor equipment.
- Screw compressor devices with the direct frequency-regulated drive are one of the most advanced types of compressors nowadays. Both manufacturers and consumers recognize this fact. They have an extremely high efficiency factor (99.9%), their performance and pressure can be adjusted, they are suitable for any application, and have smooth running of the drive. One can rightfully state that the screw compressor of this type virtually has no flaws, perhaps, only the high price of the equipment, which is, however, not an obstacle to the growing demand from consumers. Screw compressor devices with the direct frequency-regulated drive can be applied in any industry using compressed air.
Among other types of screw compressor equipment, there are diesel and rotary screw compressors.
Diesel screw compressors are used mainly when working in open areas without access to electricity. The diesel fuel serves as a power source for these compressors. Their design is very compact, they are maneuverable, convenient to transport, can operate in extreme weather conditions, at elevated temperature, humidity, dust. Their reliability and high quality indicators win you over. These advantages have contributed to the fact that diesel screw compressors have gained such popularity among users.
Rotary screw compressors were mastered in the 30s of the 20th century and have long been used in various industries. They are also very popular among users due to many positive factors. This type of compressors has its own features:
- they are equipped with worm rotors stabilizing the operation of the compressor and ensuring its endurance;
- this type is designed without valves, which reduces the load on the compressor itself;
- the compressor performance increases with the increase of the rotational speed;
- rotary screw compressors have the screw-section of various shapes;
- rotary screw compressors are characterized by their small forms.
Screw compressors also differ in the arrangement of cylinders: vertical and angle.
By the type of refrigerant used in the compressor, they are subdivided into: freon, ammonia, methyl chloride and sulfur-anhydride compressors. Only freon compressors (small) are widely used today.
By the application conditions, compressors can be regular, operated under normal conditions, and special, made in the tropical version.
The boiling point of the refrigerant defines compressors as low-, medium- and high-temperature.
By the type of cooling, they are divided into water-cooled and air-cooled compressors.
The compressor equipment is known for the diversity of its execution, which differs in design, performance, principle of operation, etc. Hence, the division of the following types:
- stationary and mobile;
- horizontal, vertical and with inclined cylinder arrangement;
- single-stage and multi-stage;
- single-cylinder and multi-cylinder.
By the medium used for compression, compressors are divided into the following types:
- gas, intended for gas or a mixture of multiple gases;
- air, intended to compress the air medium;
- special or multi-purpose compressors, used to compress various gases alternately;
- multi-service compressors, also special compressor devices intended for the simultaneous creation of excess pressure of different gases;
- recycle compressors intended for continuous circulation in a closed circuit.
Specifications of screw compressors
Screw compressors are highly competitive equipment having the following technical parameters:
- high level of efficiency (up to 95%, for reference: efficiency of reciprocating compressor units does not exceed 60%);
- performance level of the compressor can be up to 40m³/min;
- absolute pressure at the outlet up to 9kgf/cm2;
- electric motor power ranges from 45 to 315 kW, weight from 1,730 to 5,830 kg
Advantages of screw compressors
The screw compressor unit is complex technical equipment. In comparison to similar compressors, the screw unit is expensive, but it has a number of significant advantages:
- use of the screw unit as part of the design is the most advanced technological solution;
- low level of costs for the installation and commissioning of the equipment (no need to install a foundation);
- low level of vibration and noise makes it possible to install screw compressors indoors;
- no need to install the central compressor station, which allows to avoid excessive length of pneumatic lines, and thus reduce air loss;
- excellent operational features allow screw compressors to work around the clock in the conditions of optimum temperature;
- reliability and durability as a result of the improved design (no rubbing elements, high-strength air ends);
- no need to install a large capacity air tank and no pressure drops in the process;
- low-cost operation, maintenance intervals up to 8000 hours;
- resistance to overheating;
- ability to combine multiple units into a single compressor system;
- electricity savings due to high efficiency (95%), possible adjustment of the engine speed, as well as of the ability to produce amount of air necessary for the current consumption;
- lower oil content in the air at the outlet;
- compact size, light weight;
- large margin of strength makes it possible to extend the period of operation without the need for major overhaul.
Therefore, talking about positive aspects of screw compressors, we should mention, first of all, their following advantages:
- they are reliable;
- able to work for a long time without recharging (round the clock);
- easy to install and connect;
- small operating costs of the screw compressor;
- low noise level;
- equipped with the automatic control system;
- high levels of purity of the produced compressed air;
- low energy consumption per cubic meter of the air produced;
- relatively high productivity and
- high energy efficiency.
A significant plus of the above advantages of screw compressors is their fairly small size. Screw compressors are used in small-scale productions, where compressed air is consumed in small amounts. This type of low-power screw compressor devices is very economical, with good reliability in the process of application and quite easy to maintain.
The modern market of compressor products now offers versions of screw compressors, which correspond to centrifugal or reciprocating machines of identical purpose in terms of performance and capacity.
The following negative aspects can be named among shortcomings of the screw compressor equipment:
- structural complexity of the mechanisms controlling the degree of compression of the air produced at the outlet;
- need to provide an efficient oil separator and oil radiator;
- undercapacity (up to 20% of the maximum value) entails a reduction in the efficiency of the intermediate suction device.
Application of screw compressors
Due to their exceptional technical characteristics, screw compressors are used in a variety of industries:
- chemical industry (requires compressed air which has passed the high quality cleaning, as well as gas energy-saving screw units);
- medicine (reliability and minimum level of oil in the air are of great importance);
- production of polyethylene (provide efficient and low-cost blowing of containers);
- cooling systems (cooling gas exits through the ports, hence, the name "port compressor");
- machine industry and shipbuilding;
- electric-power industry;
- civil engineering (when working with dry materials such as sand and cement);
- application as a drive in installations using the energy of the compressed air;
- application as an oxidant in combustion zones for forced-air cooling.
Almost all gases can be compressed:
- chlorine gas
- hydrogen chloride gas
- natural gas
- flare gas
- blast furnace gas
- marsh gas
- lime-kiln gas
- coke oven gas
- carbon monoxide
- combinations of gaseous hydrocarbons
- cooking gas
- well gas
- sulfur dioxide
- nitrogen oxide
- vinyl chloride-based gas
Here are some more detailed examples of the application of screw compressors in various industries:
Compressed air is used for various applications in the cement industry (dust collectors, air knives, pneumatic clutches, pneumatic actuators and dust-collecting filter systems).
Power plants operate around the clock and a continuous supply of compressed air is here critical to the trouble-free operation.
Oil-free air is used in the manufacturing process (sandblasting, pneumatic tools, removal of paint and dust, tire inflation, etc.).
Air is supplied to the furnace to heat the steel and to cool the rolled steel (air supply to the burners, casting cooling for sandblasting and so on.)
Air pressure is used to transport fluids under pressure, for pressurized containers, in tanks for aeration, spot cooling, ammonia synthesis, in automatic control systems, etc.
Screw compressors are used in manufacturing processes (mixing of blends, transportation of pressurized fluids, dehydration of products, cooling of powders, during packaging, etc.).
Cooling of machine tools, compressed air for robotics, removal of scraps such as shreds, metal powder, pneumatic tools, etc.
Production of drugs, aeration tanks, for packing medicines.
Compressed air is used for bores and pneumatic tools (pneumodrill, hammers, pneumatic riveting hammers, wrenches, etc.), for paintwork, transportation of ground and waste water under pressure, construction of piles, etc.
Excavators, transportation of ore and coal using the air pressure, pumping of oxygen into mines, dust collecting filter systems.
Oil-free air is used in many technological cycles of the production process, such as mixing, spraying of powder, and dehydration of products.
Though today screw compressors are well-designed products, a great contribution of technical sciences in the form of computer simulations and mathematical analysis at the design stage make further improvements in efficiency and reduction in size and costs possible. It is clear that changes are coming in the petrochemical, chemical and gas industries, too. Screw compressors now have already proven their place in the central part of many systems and have earned a reputation of reliable, efficient, operationally flexible devices not requiring high maintenance costs.
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Upon becoming the official distributer of screw compressors (screw compressor lines), our company ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), carries out the following: finds the buyers of your products on the market, conducts technical and commercial negotiations with the customers regarding the supplies of your equipment, concludes contracts. Should a bidding take place, we will collect and prepare all the documents required for the participation, conclude all the necessary contracts for the supply of your equipment, as well as register the goods (screw compressors) and conduct customs clearance procedures. We will also register a certificate of transaction (Passport of Deal) required for all foreign trade contracts in the foreign currency control department of the authorized Russian bank so that currency transaction could be effected. If required, our company will implement an equipment spacing project in order to integrate your equipment into the existing or newly built production plant.
We are convinced that our company ‘Intech GmbH’ LLC (ООО «Интех ГмбХ»), will become your reliable, qualified and efficient partner & distributor in Russia.
We are always open for cooperation, so let’s move forward together!