Wright-Austin Type T Gas Liquid Separators

  • Wright-Austin Type T gas/liquid separator

    Type T gas/liquid separators employ the three basic principles of separation:

     

    1. Change in Velocity

    2. Torturous Path

    3. Centrifugal Force

  • Wright-Austin Type TS gas/liquid separator

    Type TS gas/liquid separators have an elongated body.

    This provides additional removal capacity, making them better for applications that have occasional "slugs" of liquid.

  • Wright-Austin Type R gas/liquid separator

    Type R gas/liquid separators have a complex, "torturous" path with multiple changes in direction which droplets cannot navigate.

    These separators handle the heaviest percentage of entrained droplets.

 

Type T centrifugal gas/liquid separators have a cylindrical shaped body oriented vertically, requiring the flow path to change directions within the separator body.  Looking at the elongated body with inlet/outlet ports 180 degrees apart and on the same plane, it sort-of resembles the letter "T".

There are four "T shaped" separator designs: T, TS, R and ST.  The difference between the T, TS and R versions is the flow rate of entrained droplets that can be removed.  The Type T separator has an entrained droplet separation capacity equivalent to 40% of its maximum weight flow capacity.  The Wright-Austin Type TS style centrifugal separator increases the separation rate to 60% of its maximum weight flow capacity due to an elongated sump.  The Wright-Austin Type R gas/liquid separator design increases separation to 90% of its maximum weight flow capacity due to increased complexity within the separator body.  The Type R is often the most compact option although due to its internal complexity it is also more expensive.  We typically compare an oversized T or TS to a smaller sized Type R to determine which configuration is best suited for a given application.

The Type T design is offered in both cast iron and custom fabricated designs.

Cast Iron Type T Gas/Liquid Separators

Cast Type T Gas/Liquid SeparatorCast iron Type T gas/liquid separators are designed to remove entrained liquid and solids from air, steam or any gaseous media compatible with cast iron.  The T design can remove entrained liquid at a rate equivalent to 40% of the maximum weight flow capacity for a given size separator body, removing entrained droplets >10 microns with 99% efficiency. Due to the cast iron design an ASME Code Stamp or CRN is not applicable.  If you require an ASME Code Stamp or CRN it will need to be a fabricated design in carbon steel, stainless steel or some other alloy.  The cast iron version is commonly used for steam and compressed air applications.

99% efficiency for removing droplets >10 microns is accomplished by creation of a powerful centrifugal vortex within the separator body.  Droplets and particles larger than 10 microns are tossed to the vessel walls where they coalesce to larger droplets and collect at the drain port.  Re-entrainment is prevented due to a vortex containment plate (VCP) located just above the drain port.  Dry gas and droplets finer than 10 microns exit through the center of the vortex and out the discharge nozzle.

There are no moving parts or serviceable components within a cast iron type T separator.  If fluid is allowed to accumulate and sit in the separator, perhaps due to a faulty drain valve, it is possible for the lower body to become severely corroded.  Other than that, cast iron T style separators have a decades long service life with zero maintenance required!

If the separated liquid is not drained from the separator body before rising above the VCP, re-entrainment is likely.  The simplest way to drain fluid from the separator is to attach a ball valve on the drain port, which can be manually opened or automated based upon a timer.  Using a ball valve risks loss of some process gas during drainage, so consider using a Type 90-AC float drain trap instead; it automates the drainage process mechanically and ensures no process gas loss during drainage.

The Wright-Austin Type ST separator is a variation of the cast iron Type T separator; it is only available in cast iron material and it is an abbreviation for "Separator Trap", thus has an internal float drain trap to drain the separated liquid from the separator sump without loss of steam/air/gas.  The cost of a Type ST separator is about the same as purchasing a cast iron Type T separator and cast iron 90-AC float drain trap separately, however installation is simplified.

Wright-Austin Cast Iron Gas/Liquid Separator Drawings (click to open PDF file)

Wright-Austin Threaded Cast Iron Type T SeparatorWright-Austin Flanged Cast Iron Type T Separator

Custom Fabricated Type T Centrifugal Separators

Gas Liquid Separator Fabricated of Carbon SteelCustom fabricated type T style centrifugal separators are manufactured using pipe or rolled plate to form the cylindrical body, enabling fabrication from steel, stainless steel and other alloys.   Type T gas/liquid separators remove entrained droplets and particles larger than 10 microns from air, gas or steam with 99% efficiency.  Type T separators have no moving or serviceable components, they are considered self-cleaning and require zero maintenance.  T style separators have a fully welded design manufactured in accordance to ASME Code and available with ASME code stamp and CRN. Since these are custom fabricated products, we can accommodate your particular specifications involving material of construction, pressure, temperature, corrosion allowance, non-standard NDT, coatings and any design enhancement which might be required for your specific application. Common features which can be added to a Wright-Austin T separator include liquid level gauge ports, inspection ports, flanged vent or drain connections and support legs.

Centrifugal separation refers to the powerful vortex created within the separator body which propels droplets and particulate > 10 microns to the inner circumference of the vessel.  The finer droplets, particles and gas exit through the low velocity area of the vortex and outlet nozzle.  Re-entrainment of the separated liquid is prevented with a vortex containment plate affixed near the bottom of the vessel, just over the drain port.

The liquid removal capacity for Type T separators is equivalent to 40% of its' maximum rated weight flow capacity for a given size separation element.  Drainage of separated liquid though the bottom drain port can be accomplished with an automatic float drain trap or ball valve.

Wright-Austin Fabricated Type T Outline Drawing (click to open PDF file)

Wright-Austin Fabricated Type T Gas-Liquid Separator Drawing

The math involved to properly size a centrifugal separator is complex because physical test results using 60ºF air were used to create baseline capacity charts.  If your application happens to involve 60ºF air, then you can simply find the intersection of your operating pressure and flow rate on the chart; the required separator size corresponds with the with the performance line to the right of that intersection.

Saturated Steam Capacity ChartAir at 60F Capacity ChartFormulas to convert other gases to air at 60F

Other temperatures and gases having a different molecular weight need to be converted to their "equivalent flow rate" based upon air at  60ºF.  The formulas to accomplish this manually are provided in our literature, however it is laborious to manually calculate the equivalent air volume and if you want to check on a range of flow rates, target a specific differential pressure or liquid volume removal capacity, you will be spending lots of quality time with your calculator!

We have designed a web-based Wright-Austin Gas/Liquid Separator Sizing Calculator to quickly determine the proper element size and to analyze "what if" calculations within seconds. The Wright-Austin centrifugal separator calculator requires four data points to use: molecular weight, temperature, gauge pressure (PSIG) and the design flow (volumetric or weight) for your application.  The sizing process and our calculator tool are described in detail in our article "Size Matters, Understanding Sizing Factors for Centrifugal Separators".