Product Comparison
AOV vs MOV
| Item | AOV | MOV | Remark |
|---|---|---|---|
| Characteristic | An actuator that automatically opens and closes a valve by rotating it with air pressure using an air motor | An actuator that automatically opens and closes a valve using the rotational power of an induction motor using an electric motor. | Distinguished by the driving method of the motor. The basic torque generation method is the same. · Electric motors have a constant rotational force. Air Air motor rotational force varies depending on air pressure. Air motors do not suffer from damage. In the case of air motors, rotational speed may vary. |
| Stability | Since electricity is not applied, explosion-proofing is guaranteed. In the case of hybrid models [pneumatic + electric] that are supplied with electricity, single-phase is possible, so electrical stability is excellent. In explosion-proof areas, safety is higher than MOV. Safety is guaranteed in case of overload. | It is safe because the inside is sealed and explosion-proof grade is certified. Explosion-proof design can be applied to explosion-proof areas. It is safe because it has an electric safety device in case of overload. | Electricity has basic safety standards and criteria. Pneumatics are safe because they are guaranteed to be explosion-proof. MOV is more economical in nonexplosion-proof areas. AOV is more stable than MOV. |
| Emergency function | When holding an air tank, the valve can be opened and closed even in a dangerous area during a power outage. | In case of a power outage, the emergency generator can be used to open and close the valve. | The economical cost burden is high when applying an emergency generator to MOV. Since the air pressure remains in the line even during a power outage, there is some room to open and close the valve. AOV is more economical than MOV. |
| Durability | Resistant to vibration, moisture, noise, etc. No accidental failures that occur in electrical and electronic devices. | It is vulnerable to vibration because it uses electrical and electronic components through PCB board and electrical signal processing. | Safety is usually 4 times higher. [MOV: 0.5G, AOV: 2G] MOV is sensitive to the external environment to the extent that the immersion heater must be placed on the substrate, etc. AOV is more advantageous than MOV in terms of component durability. |
| Installability | Installation is possible even while the line is in operation. | Installation while the line is in operation may be somewhat difficult. | AOV is often installed during line operation. MOV cannot be installed during line operation. AOV is more advantageous in terms of installability. |
| Repair | Low maintenance costs due to application of mechanical pneumatic components. | The price is high because the substrate, etc. are unitized, and if imported parts are used, the delivery period is long. | AOV is much more advantageous than MOV. |
| Economic efficiency | If there is no pneumatic line, additional costs for compressor and air piping are incurred. Air dehumidification and de-oiling are required, and continuous line maintenance is required to obtain uncontaminated air | In case of MCC supplementation or additional electrical work due to electrical capacity issues, the construction cost may be higher than the price of the MOV product. | In the case of petrochemical plants, AOV is more advantageous for the efficiency of the line used or simple automation. In the case of MOV, electrical work is required for explosion-proof areas, but since the air line is already applied, the cost efficiency of the construction is higher for AOV even if additional air line construction is performed |
| Opening and closing time | Almost the same, without much difference. | Almost the same, without much difference. | In terms of rotations per minute, the Air Motor is about 3000 RPM, and the Electric Motor is about 1800 RPM. Air In the case of the Air Motor, there is a change in time due to the compressibility of the air. When precise opening and closing times are required, MOV is more advantageous. |
| Torque control | Depending on the maker, some products have a torque switch and others do not. | Torque Switch [Open, Close] is applied basically. | MOV requires a torque switch because if there is a problem with the torque control function, it will directly lead to damage to the motor. AOV also requires a torque switch to prevent valve jamming and overload protection, but some products do not have a torque switch depending on the manufacturer. Valve를 안전하게 보호하고 제어하기 위해 Torque Switch는 AOV, MOV에 모두 적용되어야 함. |
| Etc. | When driving control is performed on site and in DCS, valve opening and closing is only possible by supplying air pressure and electricity. In the case of models that are only supplied with air pressure, air leakage, etc. may occur due to distortion of air pipes after several years of use. | Although it is a product that is supplied with electricity, there is no problem with stability because it has accumulated abundant experience and technical skills. Electricity is easy to supply. In non-explosion-proof cases, electric supply products are also useful. | AOV can be economical for manual valve automation of operating lines, automation of explosion-proof areas, and valve automation of factories with low opening/closing frequency and air supply. MOV can be more economical for non-explosion-proof areas or lines without air supply. |
Strength comparison
| AOV Strengths | MOV Strengths |
|---|---|
| If air pressure is supplied to the site, it is optimal for on-site manual valve automation. * Optimal for new valve automation If a distance of less than 50m from the valve is connected with air pressure, valve opening and closing is possible. Convenient to use when valve opening and closing is only done on-site. * If valve opening and closing is not done in DCS, MOV application is not necessary. Low installation cost when working on existing plant performance. Perfect explosion protection is possible. (AOV is driven by air pressure without electricity supply.) Low repair cost in case of failure and failure can be detected in advance. Insensitive to external disturbances such as noise and vibration, so accidental failure does not occur. * High durability due to resistance to vibration, moisture, and noise. Very safe because it only stops without damage in case of air motor failure. Low cost due to built-in emergency shutoff function. | Since the time is constant, sequence control is possible and there is no time delay. When driving control is performed on site and in DCS, valve opening and closing is possible only with electricity supply. * AOV requires air pressure and electricity to be supplied for on-site and DCS driving control. Low noise during operation. * AOV : 85dB, MOV : 50dB Additional functions such as proportional control, opening signal, and feedback signal can be added at low cost. Convenient because no separate management is required. * AOV requires management such as lubrication, dehumidification, and oil removal. Can be installed at low cost in non-explosionproof areas. Various motor capacity selections can shorten the opening and closing time of large valves. |