Cast Iron Steam Exhaust Heads

Cast Iron exhaust heads for up to 40% by weight of the units flow capacity

Wright-Austin Cast Iron Exhaust HeadWright-Austin cast iron exhaust heads are designed for long service life, the body, cover and separating element are constructed of high tensile cast iron which resists fractures and corrosion.  Cast iron exhaust heads are designed to remove entrained droplets from steam vent lines, often located on rooftops.  They remove droplets as fine as 10 microns with 99% efficiency, the droplets are sent to a common drain for reclamation or disposal.  Exhaust heads reduce the visible steam exhaust plume, reduce the loss of boiler treatment chemicals and wetting-out or corrosion of nearby surfaces.

Although an exhaust head has a sound reducing, muffler-like effect, that is not its design purpose.  Its purpose is strictly for removing entrained fluid from the vented steam, the indirect pathway reducing noise is a byproduct of its design.  There are vent mufflers designed specifically  for noise reduction, however it is not a product we offer.

ASME Code Stamps and CRN are not applicable because exhaust heads are not pressure vessels. The components to build cast iron exhaust heads are usually stocked items and shipments made within 1 week after receipt of an order. If the lead time is critical, please contact our office and obtain a lead-time estimate based upon the current manufacturing backlog.

How to Size an Exhaust Head

When sizing an exhaust head, the pressure that is used to size it should always be Atmospheric (14.7 PSIA), no matter what the application pressure is. The flow rate is the determining factor.

To calculate the pressure drop through an exhaust head, simply follow the equation stated on the Air Sizing Chart or Steam Sizing Chart.

You can also use our web based sizing tool within the navigation bar above.  PDF links to sizing charts:

Separator Sizing Chart for Air and other GassesSeparator Sizing Chart for Steam

The difference between PSIG and PSIA is the “measured” pressure is the difference between the unknown pressure and the atmospheric pressure. This difference is referred to as the gauge pressure (PSIG), whereas the true pressure, called absolute pressure (PSIA) includes atmospheric pressure. To obtain operating pressures in PSIA add 14.7 to gauge pressure PSIG.

Cast iron and fabricated exhaust heads have different dimensions and therefore different capacity ratings for equivalent connection sizes.

Please contact us for alloy materials and temperatures over 650ºF.

CONNECTION PART NUMBER
FNPT 1.40EHC
FNPT 1.540EHC
FNPT 2.40EHC
FNPT 2.540EHC
FNPT 3.40EHC
125# FF ANSI Flange 3.40EHCFN
FNPT 4.40EHC
125# FF ANSI Flange 4.40EHCFN
125# FF ANSI Flange 5.40EHC
125# FF ANSI Flange 6.40EHC
125# FF ANSI Flange 8.40EHC
125# FF ANSI Flange 10.40EHC

PDF Links to Outline Drawings and Specifications:

Drawing: Cast Iron Exhaust Heads, up to 4" ThreadedDrawing: Cast Iron Exhaust Heads, up to 10" Flanged