Inverted Bucket Steam Traps


Tunstall Corp. produces a full line of Inverted Bucket Steam Traps containing a stainless steel bucket and valve mechanism which are either in a full closed position, or a full open position to discharge condensate.

As the system starts, air and non-condensable gases vent through the orifice in the bucket; condensate also enters through the standpipe which forms a water seal in the bottom of the bucket. As steam enters the trap a simple lever mechanism attached to the inverted bucket snaps shut; then as the steam condenses the buoyancy of the bucket changes thus opening the lever mechanism, and allowing pressure to force the condensate out of the trap. This process repeats itself exactly and continuously to maximize the efficient use of energy. No cooling leg required. Refer to capacity charts when ordering.


  • High Strength Cast Iron Body
  • Hardened Stainless Steel Valve & Seat
  • Stainless Steel Bucket
  • Test Plug
  • Low Maintenance


  • Converters
  • Dryers
  • High-Pressure Drip
  • Laundry Equipment
  • Oil Preheaters
  • Pressing Machinery
  • Process Equipment
  • Steam Cookers
  • Steam Heated Vats
  • Unit Heaters


Materials of Construction
Body & Cover Cast Iron-ASTM-A-126-7/Class B
Bucket & Linkage Stainless Steel
Valve & Seat Hardened Stainless Steel
Standpipe Steel Pipe
Cover Gasket Non-Asbestos


Model 8080:
Max. Operating Pressure: 150 PSIG
Max. Allowable Temperature 366°F

Model 8181:
Max. Operating Pressure: 250 PSIG
Max. Allowable Temperature 450°F

Model Size (in.) Weight Dimensions
Number NPT (lbs.) A B C
8080 1/2 5.5 5.000 6.625 3.250
8080 3/4 5.5 5.000 6.625 3.250
8181 1/2 6 5.000 7.625 3.250
8181 3/4 6 5.000 7.625 3.250
8181 1 6 5.000 7.625 3.250