Stainless steel air preparation units are designed for use in corrosive environments, such as marine environments, oil and gas production, chemical and hostile industrial compressed air systems.
How do the stainless steel filter regulator lubricator units work?
Here, we must consider the basic working principles of the individual elements:
- Filter: The filter body has a construction that creates a cyclonic action for the incoming air. This action works to deposit water and heavier particles to the bottom of the bowl. A baffle, under the filter element, prevents the deposited water and debris being sucked back into the output air flow. Air is then forced through a filter element, the mesh size determining the minimum size of particle removed from the air flow. So, for example, a 5 micron filter will remove all particles greater than 5 micron in size.
- Regulator: The control knob works against a spring which, in turn, places load against a diaphragm assembly. The diaphragm pushes down on a valve pin connected to the valve seat and the seat drops; this allows downstream air flow from the inlet port (P1) out of the outlet port (P2). As air passes down P2, a breathe hole lets air into a chamber below the diaphragm; once pressure either side of the seat is equal, the seat closes with the aid of the spring. Downstream demand will cause a pressure drop in the chamber, opening the seat and allowing air to flow again until pressure is once more equalised and the seat closes. The process is continuous, maintaining P2 at a set value.
- Lubricator: Air flow into the lubricator creates oil droplets; all of the oil drops in the site feed dome are added directly into the downstream air flow, providing a controlled level of lubrication for downstream equipment. Oil fog lubricators are particularly suited to tools and equipment requiring heavy lubrication.
How do I select a stainless steel filter regulator lubricator unit?
By definition, the material (for example 316 stainless steel) will be required for a harsh working environment. There will likely be a requirement for the units to meet a standard, for example National Association of Corrosion Engineers (NACE) Standard MR-01-75. Products may need to be Lloyds Register Type Approved.
There are a variety of units to cater for different flow requirements. The level of filtration desired will determine the grade of filter element chosen.
Types of stainless steel units
General purpose filter, pressure regulator and lubricator units are available with ½ PTF ports; filter/regulator with ¾ PTF and regulator and filter-regulator with ¼ PTF ports. Flow for these units ranges from 7 dm3/s to ~50 dm3/s. Check data sheets for detailed specifications, including operating pressure and ambient temperature ranges.
Precision regulators and filter/regulators are also available for instrument and other high precision applications.
Typical applications of stainless steel
As stated, stainless steel air preparation units will be used in harsh, corrosive environments. Marine, oil and gas and chemical processing are typical applications. They are also ideal for applications with frequent wash-down using aggressive cleaning agents, for example the food and beverage industry.
Do I need anything else with stainless steel air preparation units?
Gauges and mounting brackets are frequently used accessories. Suitable fittings and tubing will also be required to connect the units into a compressed air system.