Skip to content
No Air BindingCorrosion ResistantField ServiceableMultiple ConnectionsHigh CapacityVacuum Breaker Option

Armstrong AIC/AIC-F/AIC-FH Series Float & Thermostatic Steam Trap

Armstrong AIC/AIC-F/AIC-FH Series Float & Thermostatic Steam Trap features ductile iron body with built-in stainless steel thermostatic air vent, eliminating air binding. Covers DN15-DN50 nominal diameters, supports threaded or flanged connections, horizontal/vertical installation, max differential pressure 3.2MPa, max capacity 28,000kg/h. Suitable for heat exchangers, steam mains, heating equipment from medium-low to high pressure applications. Robust construction, corrosion resistant, field serviceable.

Armstrong AIC/AIC-F/AIC-FH Series Float & Thermostatic Steam Trap

Product Overview ​

Armstrong AIC/AIC-F/AIC-FH Series Float & Thermostatic Steam Trap is a key device designed for efficient steam system drainage. Its core advantage is the built-in stainless steel thermostatic bellows air vent, which rapidly discharges air and non-condensable gases, completely eliminating air binding and ensuring stable system operation.

This series is divided into three categories by nominal diameter: AIC DN15-DN25 Series, AIC DN40-DN50 Series, and AIC-FH Integral Flange Series, each suited for different pressure ratings and operating conditions. Internal components are made of stainless steel with enhanced treatment, providing robust construction with excellent corrosion and back pressure resistance for long-term reliable operation under high loads. Field serviceable design reduces maintenance costs.

Applications ​

AIC DN15-DN25 Series ​

Suitable for systems requiring continuous drainage and rapid air venting, especially for applications that cannot tolerate pressure fluctuations from intermittent discharge:

  • Medium-low pressure steam mains
  • Pressure-sensitive heat exchangers
  • Steam equipment requiring high operational stability

AIC DN40-DN50 Series ​

Suitable for applications with significant pressure fluctuations or heavy condensate loads:

  • Various industrial heating equipment
  • Drying equipment
  • Petrochemical distillation tower equipment
  • High-load steam systems

AIC-FH Series ​

Suitable for systems requiring continuous drainage, rapid air and non-condensable gas venting, while accommodating pressure fluctuations from intermittent discharge:

  • Medium-low pressure steam mains
  • Various heat exchangers
  • Equipment requiring integral flange connections

Technical Specifications ​

Operating Pressure Parameters ​

SeriesNominal DiameterMax Working PressureMax Working DifferentialOperating Temp
AICDN15-251.7MPa @ 232°C1.4MPa @ 232°C232°C
AICDN40-502.5MPa @ 300°C3.2MPa @ 300°C300°C
AIC-FH-4.0MPa @ 300°C2.1MPa300°C

Vacuum Breaker Parameters ​

ParameterValue
B (mm)6
C (mm)28
D (mm)17
Max Working Pressure1.0MPa

Connection Types and Standards ​

SeriesConnection TypeStandardApplicable Sizes
AICThreadedBSPT/NPTDN15-25, DN40-50
AICFlangedHG20592 PN16 RFDN15-25
AICFlangedHG20592 PN40 RFDN40-50
AIC-FHIntegral FlangeASME B16.5 CL150, HG20592 PN25-

Material Specifications ​

Armstrong AIC DN15-DN25 Float & Thermostatic Steam Trap - Structure DiagramArmstrong AIC DN40-DN50 Float & Thermostatic Steam Trap - Structure Diagram

ComponentAIC Series (DN15-25)AIC Series (DN40-50)AIC-FH Series
Body, CoverDuctile Iron ASTM A536 60-40-18 (QT400-18)Ductile Iron ASTM A395 EN1563 EN-GJS-400-18U 60-40-18 (QT400-18)Ductile Iron ASTM A536
Disc, SeatHardened Chrome Alloy Steel 440Hardened Chrome-Moly Steel ASTM A747 Gr.CB 7CV-1, H-90Hardened Chrome Alloy Steel 440
Mechanical Internals304 Stainless Steel304 Stainless Steel304 Stainless Steel
FloatStainless SteelStainless SteelStainless Steel
Body/Cover GasketReinforced GraphiteReinforced GraphiteReinforced Graphite
Air VentNickel-based Alloy BellowsNickel-based Alloy BellowsNickel-based Alloy Bellows
BoltsCarbon Steel SAE Grade B2Carbon Steel ASTM A194 Gr2HCarbon Steel SAE Grade B2

Dimensions ​

AIC Threaded Connection Dimensions (Unit: mm) ​

Armstrong AIC Threaded Float & Thermostatic Steam Trap - Dimension Drawing

InstallationDNABCDE
Horizontal15135175160—94.5
Horizontal20135175160—94.5
Horizontal25135175160—94.5
Horizontal40278326270289—
Horizontal50278333300289—
Vertical40281386242350—
Vertical50297398275350—

AIC Flanged Connection Dimensions (Unit: mm) ​

Armstrong AIC-F Flanged Float & Thermostatic Steam Trap - Dimension Drawing

InstallationDNABDEL (PN16 RF)L (PN40 RF)L (PN25 RF)
Horizontal15142175—96150——
Horizontal20147180—96150——
Horizontal25152185—96160——
Horizontal40278411334——230230
Horizontal50278420334——230230
Vertical40278426350——230230
Vertical50278434350——230230

AIC-FH Integral Flange Dimensions (Unit: mm) ​

Armstrong AIC-FH Float & Thermostatic Steam Trap - Dimension Drawing

InstallationDNABDL (ASME B16.5 CL150 RF)
Horizontal25201334276160

Weight ​

AIC Threaded Connection Weight (Unit: kg) ​

InstallationDNWeight
Horizontal155.2
Horizontal205.3
Horizontal255.4
Horizontal405.1
Horizontal505.1
Vertical4032
Vertical5032

AIC Flanged Connection Weight (Unit: kg) ​

InstallationDNWeight
Horizontal156.15
Horizontal206.55
Horizontal257.3
Horizontal4034
Horizontal5034
Vertical4034
Vertical5034

AIC-FH Integral Flange Weight (Unit: kg) ​

InstallationDNWeight
Horizontal2513.6

Note: For flanged connections other than ASME B16.5 standard, consult supplier for weight information.

Ordering Information ​

Required Information When Ordering ​

  1. Product model (AIC/DN15-25, AIC/DN40-50, AIC-FH)
  2. Nominal diameter (DN15-DN50)
  3. Pressure rating or orifice size
  4. Connection type and standard
  5. Installation orientation (horizontal/vertical)
  6. Options (e.g., Vacuum Breaker VB)

Model Designation Rules ​

  • Add "VB" suffix to model number for integral vacuum breaker configuration (e.g., AIC DN15 VB, AIC-FH DN25 VB)