The Mining Industry has a diverse number of operations that require the control of the flow of various fluids in different processes. It cannot be discredited that the mining environment is very harsh, and therefore equally tough actuators are required for such operations. The selection of such suitable actuators becomes key to prolong the life in different applications, and to save on costs resulting from additional procurement due to poor quality valve actuator. At COVNA, we provide Electric Valve Actuators and Pneumatic Valve Actuators that meet these needs. In this article, we discuss the application of these COVNA actuators in the Mining Industry with an overall aim of making it simpler for users to make any selection.
Where Can One Apply Actuators In The Mining Industry?
Electric and pneumatic valve actuators in the mining industry has a widespread application. These vary from underground applications such as dewatering pumps, HVAC, dust control and others. Other applications include the ore processing sections where there are processes such as pumping of slurry, dewatering, floatation, and smelting which require the control of the flow of fluids either in the form of stopping or regulating the flow. Some areas may have an inherent explosive environment – these are areas such as those that contain coal dust. Auxiliary services such as power generation also require actuated valves to be in operation, and it may be necessary in this scenario to have high precision control. In all these cases of application in the mining industry, it is apparent that there is a need for the rugged type of applications that suit the abrasive nature of the environment, lest there may be undesired wear and tear which may compromise the operation. The following are examples of where actuators may be applied.
- Fan Dampers
- Fuel control valves
- Reagent control valve
- Boiler feedwater valves
- Air compressor valves and may other applications
Why Select COVNA Valve Actuator in Mining?
COVNA offers the choice of two main actuators – pneumatic and electric ones for use in the mining industry. Of course, each actuator has different applications, and various criteria are used to establish the best type of actuator to be used. When it comes to actuators in mining, the user needs to ensure the following are provided by the actuator:
- Reliability– Both COVNA Pneumatic Valve Actuators and Electric Valve Actuators are made of strong materials that resist abrasion and ensures a longer life of the actuators. This gives COVNA actuators a good mark in providing reliability in the mining environment. Additionally, the electric actuators are rated at IP67, making them suitable for most of the mining environments which may have water.
- Maintenance– COVNA actuators are well designed with optimum running and maintenance costs. Special care is taken to select the most resistant material in the manufacture of the valves. Additionally, manuals for installation, maintenance, and part identification are provided by COVNA for quick and easier identification and subsequent ordering of spare parts.
- Flexibility– We recognize that there may be unplanned events happening in the operation of a mine. An unforeseen power cut or failure in a compressed air system should not result in the non-operability of the actuator. At COVNA, we realise that besides the fail-safe proof of the actuators, there is a need to enhance operability by adding a manual operation of the valves. The electric actuator and some pneumatic actuators can be operated in manual mode, allowing operators to open or close a valve manually should the need arise such as a case of an electricity outage.
The COVNA AT series pneumatic valve actuators has a lot of features that make it suitable for application in the mining industry. The actuators come with the following features:
- Stainless Steel fasteners which are suitable for the abrasive environment.
- Bi-directional stroke adjustment.
- Versa view continuous indictor for physically establishing the actual position of the valve opening.
- NAMUR mounting
- Bottom mounting that that is designed to conform with the latest standards under ISO 5211, DIN3337 standards
- The actuator body, made of aluminum can be treated with hard anodized powder polyester
The pneumatic actuators are designed for work with dry or lubricated air at rated pressures. The general operating temperatures range from -20 o C to 150 o C which should meet most of the requirements for operating in the plant. The serial number for each actuator is available for ease of tracking and part identification. Additionally, there is an available manual with the model number and air requirements for reference purposes during the selection, installation and operation phase of the actuator.
Other than the pneumatic actuator, COVNA also has a selection of electric actuators with various applications in the mining industry. The electric actuator has the following characteristics:
- The body is made of hard aluminium alloy treated by hard anodic oxidisation and coated with polyester powder which makes it resistant to abrasion and corrosion.
- Fully enclosed cage motor with class F insulation that makes it suitable to avoid overheating and consequent fires due to this.
- Provision for manual override which allows for the operation of the actuator to open or close a valve if there is a power outage. This is very essential when some operations have to be done to ensure plant safety or maintain quality whilst there is an outage.
- IP67 rating which makes the actuators suitable for the mining industry where there is water. However, when doing an installation outdoors, it is recommended to install an additional cover on top of the actuator to prolong its lifespan.
- ISO 5211, DIN3337 for connection with the valve which makes COVNA electric actuators suitable for universal application.
- The actuator also comes with a standard manual with instructions for installation, circuit diagrams, and dimensions. Additionally, there is a section for troubleshooting should one face operational challenges when using the valve actuator.
- An Indicator is available for checking and monitoring the position of the valve when the electric valve actuator is in operation.
- Limit switches – some available limit switches prevent the actuator from operation beyond defined limits.
- The electric valve actuators have a ±0.5 % tolerance, with a 0% mechanical repeatability error and a 0 damping
The electric valve actuators are designed to work in an environment with a temperature range of -30 to 60 o C, which should meet most of the needs of the mining environment. There is also a selection of brackets to use when mounting in the account of varying fluid temperatures. The guideline is available in the manual for the electric actuator manual.