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Did you know: Armstrong has less than 1% annual employee turnover at the main manufacturing facility in Three Rivers, MI, USA.
Disc Steam Traps
The Controlled Disc (CD) Steam Trap is a time-delayed device that operates on the velocity principle. It contains only one moving part, the disc itself. Because it is very lightweight and compact, the CD trap meets the needs of many applications where space is limited. In addition to the disc trap’s simplicity and small size, it offers advantages such as resistance to hydraulic shock, the complete discharge of all condensate when open and intermittent operation for a steady purging action.
Operation of controlled disc traps depends on the changes in pressures in the chamber where the disc operates. The Armstrong CD trap will be open as long as cold condensate is flowing. When steam or flash steam reaches the inlet orifice, velocity of flow increases, pulling the disc toward the seat. Increasing pressure in the control chambers snaps the disc closed. The subsequent pressure reduction is necessary for the trap to open. The heating chamber in the cap and a finite machine bleed groove in the disc control the pressure reduction. Once the system is up to temperature, the bleed groove controls the trap cycle rate.
Unique heating chamber
The unique heating chamber in Armstrong’s Controlled Disc Trap surrounds the disc body and control chamber. A controlled bleed from the chamber to the tap outlet controls the cycle rate. That means that the trap design—not ambient conditions—controls the cycle rate. Without this controlling feature, rain, snow and cold ambient conditions would upset the cycle rate of the trap.
CD-33/CD-33C disc trap
The Armstrong CD-33 is a disc-style trap designed to control the trap’s cycle rate. By reducing the cycle rate, the Armstrong CD-33 will have a longer service life than typical disc traps. This enhanced performance will ensure that maintenance time is minimized and steam costs are greatly reduced.
The CD-33 is designed with three discharge ports, which offer stable disc operation and thereby extend trap service life. The capacities of the Armstrong CD-33 have been engineered specifically for the following applications: large steam main drips, process equipment and HVAC heating equipment on constant pressure.
The CD-33L (low capacity) trap is designed for the low-capacity applications of steam main drips and steam tracing lines. The CD-33 Series will last longer than disc traps with excessive capacity ratings.
To review Armstrong disc traps by series, review the list below and choose the series you want from the menu above.
CD-33 Series Disc Trap
For steam pressures up to 600 psig (42 bar) . . .
Capacities to 2,500 lb/hr (1134 kg/hr)
CD-3300 Series Disc Trap
All stainless with 360° connector
For steam pressures to 450 psig (31 bar) . . .
Capacities to 800 lb/hr (363 kg/hr)
CD-40 and CD-60 Series Controlled Disc Trap
Carbon steel
For pressures to 600 psig (41 bar) . . .
Capacities to 2,850 lb/hr (1295 kg/hr)
Request a quote for an Armstrong Steam Trap Survey
Request a Steam System Assessment