The control kind with screw different compressor and energy-saving effect are comparative
Current and energy-saving environmental protection already made the main development trend of economic society, air compressor is reduce airy facility to enrage equipment to offer about bad news, and great majority moves continuously, the energy that accordingly its waste is very big, corresponding also have space of very large energy-saving latent capacity. What is the mainstream tendency that prospective air compressor develops? The individual thinks, the road of energy-saving environmental protection will be among them a very important way.
One, screw compressor all sorts of control means
The element of the consideration when type selecting of screw pneumatics machine is very much, must take care of highest air consumption and consider certain surplus, but when moving daily, air compressor is not always is to be below rated exhaust operating mode. According to statistic, there is rated cubage flow only in the average load of Chinese air compressor 79% the left and right sides, the power comsumption index that when can seeing compressor type selecting, needs to consider rated load operating mode and partial load operating mode.
All screw pneumatics machine all have capacity adjustment function, the measure that just implements has different. Familiar pattern has ON/OFF to load / uninstall adjust, transfiguration of frequency conversion of inspiratory reduce expenditure, electric machinery, pilot valve, these adjustment combination of OK also and agile ground uses means will optimize a design.
In compressor lead plane can below the case with particular effect, can from compressor overall and aspirant travel optimizes control means to achieve farther energy-saving purpose, achieve integrated and energy-saving result actually in the applied domain of air compressor thereby. The applied range of screw pneumatics machine is wider, find very hard suit all situations and completely efficient control way, need basis uses circumstance integration analysis actually, so that select corresponding and right control kind, 4 kinds the following and brief introducing that control means commonly to include its main characteristic and utility.
1, ON/OFF to load / uninstall control
ON/OFF to load / uninstalling control is to compare traditional, simpler control way, its function is the measurement that uses tolerance according to the client, self-adjusting compressor enters the switch of gas a powerful person, make compressor to load or uninstall, in order to reduce the wave motion of air feed pressure. There is the electromagnetism a powerful person, a powerful person that take energy of life in this control, put empty a powerful person and control cop.
When the rated capacity that the client is equal to with tolerance or is more than aircrew, start / uninstall electromagnetism a powerful person to lie so that electric state controls pipeline not to guide to connect, compressor lead plane enters gas a powerful person to be opened completely below inspiratory vacuum action, aircrew maintains full load condition to move.
When the client is less than rated capacity with tolerance, the pressure of compressor pipeline will be slow rise, when the platoon baric China arrives and exceed aircrew to uninstall pressure, compressor turns into discharge carry to go. Start / uninstall electromagnetism a powerful person to control pipeline to guide at the condition that break phone, it is enraged all the way go closing the valve that take energy of life; The pressure that another gas goes to hitting open sky a powerful person to make canister of oil gas depart medium is put empty, till pressure of coal tub interior stabilizes oil gas segregator (it is 15 ～ 35PSI) commonly, this opportunity group will move below inferior back pressure, keep empty hold position.
Increase with tolerance when the client when making pipeline pressure drops to provide a value, aircrew continues to add carry to go. Start right now / uninstall electromagnetism a powerful person to get report, control pipeline does not guide, nose enters gas a powerful person to keep the biggest below inspiratory vacuum action degree. The metabolic machine that uses tolerance according to the client side so relapses to load, those who uninstall move. To load / the main characteristic that uninstalls control means is lead plane enters gas a powerful person to be opened completely only, close 2 kinds of position completely, the moving condition of the machine has to load only, uninstall, stop automatically machine 3 kinds of condition.
To the client, compressing air is allow a lot of but do not allow to be not worth, change character, the capacity of air compressor is to allow big, do not allow small. Accordingly, be more than when unit capacity when using tolerance, aircrew meets pneumatics machine to be uninstalled automatically, with maintaining capacity is mixed maintain a balance with tolerance.
2, inspiratory throttle control
Inspiratory reduce expenditure controls what means needs according to client place to adjust with tolerance the volume that compressor takes tolerance, so that achieve balance of supply and demand, main element includes the adjuster of electromagnetism a powerful person, pressure, a powerful person that take energy of life to wait. When the rated capacity that is equal to aircrew with tolerance, a powerful person that take energy of life is opened completely, aircrew will be in be fully loaded with condition next moving; When be less than rated capacity with tolerance, control gas district is self-adjusting leave into what enrage a powerful person degree, control takes the volume of tolerance. The compressor aircrew that is 8 ～ 8.6bar in the light of an actuating pressure now runs 4 kinds of operating mode in the process, introduce inspiratory reduce expenditure to control the function of means respectively.
(1) starts operating mode 0 ～ 3.5bar
After compressor aircrew is started, a powerful person that take energy of life is being shut, force of coal tub middling pressure builds oil gas segregator quickly; Should achieve set time can automatic switch arrives be fully loaded with condition, a powerful person that take energy of life relies on true suction to enrage action to be opened slightly.
(2) convention operating conditions 3.5 ～ 8bar
After force of systematic internal pressure exceeds 3.5bar, develop valve of the least pressure to make compress air to be in charge of into person air feed, computer board pressure of cop of real time monitoring, a powerful person that take energy of life is opened completely.
(3) tolerance adjusts operating mode 8 ～ 8.6bar
When cop pressure exceeds 8bar, control enrages road adjustment to enter those who enrage a powerful person to leave degree, make capacity and balance with tolerance photograph, during this capacity adjusting range is 50% ～ 100% .
When need to decrease with tolerance when place or needing to use gas, when cop pressure exceeds set to be worth 8.6bar, control gas district closes the valve that take energy of life and lay open sky a powerful person, release the pressure in canister of oil gas depart; Aircrew moves below very low back pressure, bad news can decrease.
Fall when cop pressure when the lowermost pressure to set, control gas district is shut put empty a powerful person, open the valve that take energy of life, aircrew changeover moves for to load operating mode.
Inspiratory reduce expenditure controls what take gas a powerful person through be opposite to open degree of control, adjust then into tolerance, reduced the power comsumption of compressor thereby, reduced frequent to load / uninstalled frequency, because this has certain energy-saving effect.
3, frequency control control
Rotate speed of compressor frequency conversion adjusts control is the rotate speed that passes change drive electric machinery, adjust then the rotate speed of compressor will adjust capacity. The function of the tolerance regulating system of frequency conversion compressor is the measurement that uses tolerance according to the client, the air demand that the rotate speed that changes electric machinery through frequency conversion will come to cooperate constant change, so that achieve balance of supply and demand.
Basis of aircrew of every frequency conversion of model different, the transducer when set has aircrew to move actually is the biggest output frequency and electric machinery are highest rotate speed. When the client is equal to the rated capacity of aircrew with tolerance, frequency changer group adjusts the frequency of frequency conversion electric machinery and increase lead plane rotate speed, aircrew is in be fully loaded with condition next moving; When be less than rated capacity with tolerance, frequency changer group will reduce lead plane rotate speed thereby through reducing the frequency of frequency conversion electric machinery, reduce accordingly into tolerance; When the client stops to use gas, the frequency of frequency conversion electric machinery falls to lowest, shut a powerful person that take energy of life to take energy of life no longer at the same time, aircrew is in carry condition to move below inferior back pressure for nothing.
The drive electric machinery that matched stack of compressor frequency changer has its rated power is certain, but the actual axis power of electric machinery follows his laden, rotate speed is direct and relevant. Compressor aircrew uses frequency control, the case that drops in load reduces rotate speed when similarly hereinafter, can improve the work efficiency when light convey by vehicles goes greatly, at the same time can very adjust continuously conveniently, maintain capacity and the stability that discharge baric force.
Frequency conversion compressor is opposite at labour frequency compressor for, drive motor needs to be frequency conversion electric machinery, deserve to transducer is reached corresponding electronic-controlled ark, cost will be accordingly higher. So, choose frequency conversion compressor the first time investment cost is bigger, rate of transducer itself have rendered great service is used up and transducer comes loose the reason such as hot ventilated limitation, it is span of user air consumption only big air compressor, what just often have choice transducer at inferior load is necessary.
The main good point of frequency conversion compressor is as follows:
(1) energy-saving effect is apparent;
(The 2) electric current that start is small, small to concussion of electrified wire netting;
(3) exhaust pressure is stable;
(4) aircrew noise is low, frequency of electric machinery movement is low, without add often uninstall noise.
4, pilot valve transfiguration adjusts
Pilot valve transfiguration adjusts the working principle that controls fashion is: Go changing compressor lead plane to compress antrum to reduce volume effectively inside through an orgnaization, adjust thereby the capacity of compressor. Control of control, as inspiratory as ON/OFF throttle and frequency conversion control belong to compressor principle of exterior pilot work differs somewhat, pilot valve transfiguration adjusts the structure that means needs to change compressor itself.
Cubage discharge adjusts pilot valve is screw compressor is used adjust the component of a kind of structure of cubage discharge, use this kind to adjust if the machine of means pursues the structure of rotational pilot valve of 1, the bypass opening that as gyroidal as rotor shape answers relatively leaves on air cylinder wall, when these aperture were not covered, gas is OK from the eduction in these aperture. What use pilot valve also common calls ” of “ helix a powerful person, body of a powerful person is gyroidal shape, can cover when it rotates or open with the bypass aperture that compresses antrum to be linked together.
When the client decreases with tolerance, roll of helix a powerful person opens bypass hole, the partial air that makes attract a person passes the population of bypass aperture regurgitate that reduces antrum bottom without compressing, do not participate in compress, be equivalent to reducing participate in the screw length that reduces effectively to reduce effective job volume namely, so effective compression result reduce greatly, when realizing partial load energy-saving. Program of this kind of design can offer continuous cubage flow to adjust, the capacity adjusting range that can come true commonly 50% ～ 100% .
The working principle signal that pilot valve transfiguration adjusts sees a picture 2 ～ 4.
Structure of helix a powerful person can be used at the compressor of any model, accord with the concept of the ” of “ green industry that people advocates increasingly.
1, all sorts of control means contrast integratedly
All screw pneumatics machine all have tolerance adjustment function, the measure that just implements has different, familiar pattern has ON/OFF to load / uninstall adjust, suck gas reduce expenditure, electric machinery frequency conversion adjustment, transfiguration adjustment, these adjustment combination of OK also and agile ground uses means will optimize pneumatics machine to control means to design.
For more intuitionistic comparison all sorts of control adjust the characteristic of means and function actor bad, means of these a few kinds of tolerance adjustment sees a table 1.
Control means capacity – curve of axial power change is comparative
Compare what summary comes out to compare power change graph through checking data in great quantities, the energy-saving effect that can see transfiguration adjustment, frequency conversion adjustment from which is very apparent.
2, frequency conversion adjustment is as comparative as transfiguration adjustment
The economy of compressor should consider at least from 3 respects:
(1) compressor is energy-saving;
(Of 2) spare parts change cycle and spare parts price;
(The price of 3) compressor and purchase cost.
Before how many what mattered to the fixed fee that the user pays to run this one product every year at 2 o’clock, opposite at big are for 3 o’clock, first consideration answers when the economy that considering compressor. At the same time the economy of compressor and applicability are inseparable, good in A circumstance applicability economic compressor, do not apply to B circumstance certainly, not certain also economy.
Turn very big situation considering the moving cost, quantitative change that use gas, compressor of choice screw air should actor or actress choose compressor of frequency conversion drive or transfiguration adjustment compressor. The actor weakness of transfiguration adjustment compressor and compressor of frequency conversion drive is as follows quite:
(1) is in economy respect: Advantage of cost of transfiguration adjustment compressor is clear, competitive advantage is had on the price; The cost of frequency conversion type is 1.3 times of transfiguration type commonly.
(2) is in energy-saving effect respect, should see a machine move in why to plant below condition:
Frequency conversion adjustment applies to capacity 30% ～ the machine of frequency of adjusting range labour of 100% is rated when rotate speed, its compress power comsumption and close of labour frequency machine, add transducer itself to need to use up 2% ～ the specific power consumption of 3% , overall the specific power consumption that power comsumption exceeded labour frequency opportunity. That is to say, it is with tolerance when the client rated when the 90% above that use tolerance, use frequency changer to be able to increase specific power consumption instead. This also is why when machine of a few pneumatics uses a lot of clients together, the reason that the choice is frequency changer among them. Transfiguration adjustment applies to capacity 50% ～ the adjusting range of 100% , and in 90% ～ 100% season can effect excel frequency conversion adjusts.
(3) gets used to ability in harsh environment: Transfiguration adjustment compressor is more outstanding than frequency changer, fault rate is extremely low, it is more convenient than frequency changer, easy to safeguard and be repaired.
Above analysis and screw pneumatics machine compare pattern of commonly used 4 kinds of control, avery kind of controls means to have its character and applicable field, choose right control kind to be able to reduce a lot of meaningless waste really. But, the standard with how choose right control kind to be done not have however proper or formula but endowment apply, still must rely on experience, record and experiment analysis to be judged quite.
Need of a lot of moment ties kind of a few kinds of control together apply rise, commonner inspiratory throttle control and pilot valve transfiguration adjust to load of combination, ON/OFF / uninstall control of timing of control and combination of frequency control control, transfiguration and frequency control to control combination, so sufficient play commands the advantage of means individually, in order to produce a the biggest energy-saving result.