401-SH/501-SH Series Inverted Bucket Superheat Steam Traps


Carbon steel or stainless steel for vertical installation

For pressures to 1,540 psig (105 bar) . . .
Capacities to 1,300 lb/hr (590 kg/hr)

Armstrong’s 401-SH/501-SH Series inverted bucket superheat trap line is made for overcoming the difficult combination of superheat and high pressure/low load service.

To survive this most severe steam service, Armstrong created an inverted bucket trap with a unique accumulation chamber. The chamber collects sufficient condensate to ensure full discharge cycles. A cup in the chamber floats up and down on the steam inlet tube, sealing it off as the condensate level rises.

At the same time as the chamber collects condensate, steam continues to flow under the bucket, making sure that the discharge valve closes tightly until the condensate rises into the trap body and the bucket falls down. The operation is on/off, no throttling or dribbling. In addition, you get all the familiar benefits of an inverted bucket steam trap.

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    High resistance to wear, corrosion and water hammer with no gaskets.

    Operation against back pressure

    A unique leverage system multiplies the force provided by the bucket, to open the valve against system pressure.

    Freedom from dirt problems

    The mechanism is located at the top. No dirt can collect on the orifice. Small particles of dirt will be held in suspension until discharged by the full differential purging action.

    Zero steam loss

    The discharge orifice is surrounded by a water seal, which prevents live steam loss. Automatic air venting is provided by a small hole in the bucket.

    Trouble-free operation

    Inverted bucket traps require no adjustment. They do not allow condensate backup and are resistant to water hammer.