Armstrong AB-3000 Bimetallic Steam Trap operates by the effect that rising temperature has on bimetallic elements. It adjusts itself to changing conditions, as the increasing pressure on the valve is compensated by the curving of the bimetallic elements caused by the increasing temperature. At start-up, the bimetallic element is contracted and the valve is fully open, removing large condensate loads and non-condensable gases. When the system reaches steam temperature, the element expands, pulling the valve stem to close the valve.

Armstrong’s AB-3000 has a sealed, stainless steel body that is lightweight, compact, and highly resistant to corrosion. The AB-3000 is repairable (body and cap can be unscrewed). It is piped through the Armstrong 360° Universal Connector or Trap Valve Station (TVS). This makes it easy to install and replace, as the trap can be removed while the connector remains in-line, saving labor costs and increasing flexibility.

Maximum Operating Conditions

• Maximum allowable pressure (vessel design): 28 bar @ 343°C (400 psig @ 649°F)
• Maximum operating pressure: 22 bar (319 psig)
• Maximum back pressure: 99% of inlet pressure

Materials and Connections

Connections: Screwed BSPT and NPT, Socketweld, Flanged DIN (PN40) or ANSI (welded).

Part	Material
Body	ASTM-A240 304L Stainless Steel / ASTM-A479 Type 304
Cap	ASTM-A351 Gr CF8
Valve	440F / AICI-440C Chrome Steel
Seat	303 Stainless Steel
Elements	Nickel Plated Bimetallic Disc
Strainer	304 Stainless Steel
Gasket	304 Stainless Steel Non-asbestos

Dimensions and Weights

Pipe Connections	15 mm (1/2")	20 mm (3/4")	25 mm (1")
"C" Face-to-Face (screwed & SW)	60 mm	60 mm	N/A
"CC" Face-to-Face (flanged PN40)	150 mm	150 mm	160 mm
Weight (screwed & SW)	1.9 kg	1.9 kg	N/A
Weight (flanged PN40)	4.3 kg	4.5 kg	4.7 kg

Note: Standard flanges are in carbon steel, stainless steel flanges are optional. Other flange sizes, ratings, and face-to-face dimensions are available on request.

Capacity

• A: Cold Water
• B: Hot Condensate

Installation

Before installation, verify that the maximum allowable pressure/temperature and maximum operating pressure of the trap are sufficient to handle the system design pressure and temperature.

1. Before installing the trap, ensure the line is clean. Blow down any strainers ahead of the trap.
2. Install the trap so that it is accessible for inspection and repair, below the drip point and close to the vertical drip leg.
3. The trap must be installed on a 2-bolt connector block (TVS-4000, IS2, or Standard Connector). Armstrong recommends the trap be installed in a horizontal line.
4. Proper piping and drip legs of adequate size and diameter are essential for successful operation.
5. Isolation valves are needed before and after traps. When starting a new trap, be sure to open the valve slowly.

WARNING

Due to the high temperatures of steam, it might be necessary to guard the traps for personnel safety.

Drip Leg Sizing

Steam Main Size (in)	Drip Leg Diameter (in)	Supervised Warm-Up Min Length (in)	Automatic Warm-Up Min Length (in)
1/2	1/2	10	28
3/4	3/4	10	28
1	1	10	28
2	2	10	28
3	3	10	28
4	4	10	28
6	4	10	28
8	4	12	28
10	6	15	28
12	6	18	28
14	8	21	28
16	8	24	28
18	10	27	28
20	10	30	30
24	12	36	36

Maintenance and Repair

High-pressure drip traps should be tested at least three times per year. Normal trap operation is indicated by the trap discharging condensate continuously (modulating) or in cycles (on-off), accompanied by large amounts of flash steam.

DANGER

Equipment under pressure - Operating temperature > 100°C Make sure the trap is cold and depressurized before handling!

Replacement of Bimetallic Elements and Screen (AB-3000)

1. Remove the steam trap from the connector block by taking the two bolts out.
2. Unscrew and lift the cap.
3. Unscrew and replace the bimetallic elements.
4. Important: The distance between the flat bimetallic elements and the seat should be 2 mm.
5. Clean or replace the screen.
6. Replace the gasket.
7. Put the cap back on the body and screw the cap tight.
8. Bolt the trap back to the connector block.

Troubleshooting

1. Cold Trap - No Discharge No condensate or steam coming to trap.

• Stopped or plugged strainer ahead of trap.
• Broken valve in line to trap.
• Pipe line or elbows plugged.
• Pressure reducing valve out of order.
• Isolation valves are off/closed.

2. Steam Loss If the trap leaks or blows live steam, trouble may be due to:

• Valve may fail to seat.
• Piece of scale lodged in orifice.
• Worn parts. (Note: Do not confuse flash steam with live steam loss. Hot condensate forms flash steam when released to lower pressure.)

3. Continuous Flow

• Trap not up to temperature. Allow more time for condensate removal (on start-up).
• On large loads, the trap is working fine as designed.