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  • wld1500s-400x400
  • WLD1500-b-400x400
Technical Specification
Max. Operating Pressure (psig)200
Max. Operating Temperature450°F
Design Pressure250 PSIG up to 450°F
Temperature Rating450ºF @ 250 PSIG
Material Specification
BodyCast Iron,ASTM A-278 Class 30
CoverCast Iron,ASTM A-278 Class 30
NutsHigh Tensile Steel
GasketNon-Asbestos Fiber
BucketStainless Steel
BoltsHigh Tensile Steel
ScrubberStainless Steel
Seat AssemblyStainless Steel
Lever Stainless Steel
ValveHardened Stainless Steel
SeatHardened Stainless Steel
Integral strainerStainless Steel
Cross Reference
Spirax Sarcon/a
Product Overview
The WLD1500 Series Inverted Bucket Liquid Drain Traps are recommended for the removal of liquids from compressed air systems. A scrubber wire is used to keep bleed hole on top of inverted bucket from clogging due to oil that may be present in the water being drained. Oil mixed with water is typically found on compressed air systems.
• Hardened stainless steel valves and seat
• Only two moving parts
• Scrubber wire in air vent of bucket
• Discharge orifice at top of trap reduces potential for clogging
• In-line repairable
How It Works
When there is condensate in the system, the inverted bucket inside the liquid drain trap rests on the bottom due to its weight; with the valve in the open position. This allows liquid entering the trap to be discharged through the seat orifice located at the top. When air enters the trap, the bucket floats to the surface and closes off the discharge valve, containing the air in the system. Eventually, air is bled off through a small hole in the top of the bucket and the bucket sinks; repeating the cycle.
Selection / Sizing / Capacities
Determine the capacity (lbs/hr) required at the specified differential pressure. Locate differential pressure on capacity chart; move down column to capacity required. Make sure to select the correct model based on the maximum inlet  pressure.

Capacity in lbs/hr is based on differential pressure across the drainer. Select a model with an equal or higher PMO (max. operating pressure) than the maximum inlet pressure to the drainer. If the pressure to the drainer exceeds the PMO, the drainer may not open. If discharging to atmosphere, the differential pressure is equal to the inlet pressure.

Required to drain 200 lbs/hr at a differential pressure of 5 PSI. The maximum inlet pressure is 30 PSIG.

Select Model:
WLD1521-13-N, 3/4” NPT, with strainer, capacity up to 220 lbs/hr based on 5 PSI differential pressure.

Dimension and Weights
Installation and Maintenance
Installation should include isolation valves for maintenance purposes. Trap must be installed in upright position to function properly. It may be necessary to prime the bucket trap by filling it with water through the priming port prior to startup.

Close isolation valves prior to any maintenance. All working components can be replaced with the drain trap remaining in the pipeline. Repair kits include lever & seat assembly, strainer screen and gaskets. For full maintenance details see Installation and Maintenance Manual.
Sample Specification
Drain trap shall be an inverted bucket trap design with cast iron body, all stainless steel internals, hardened valve & seat, plus a scrubber wire. The unit shall be in-line repairable.