PT23 / PT23L Inverted Bucket Steam Trap
Cast iron inverted bucket steam trap with an integral strainer and stainless steel internals for equipment drains on medium to heavy, intermittent condensate loads, rated to 16 bar(g) and 220°C.
Specifications
- Sizes
- DN 15, 20, 25
- Operation
- Intermittent, cyclic (density difference between steam and water)
- Max allowable pressure (PMA)
- 16 bar(g)
- Max allowable temperature (TMA)
- 220°C
- Max operating back pressure
- 90% of inlet pressure
- Min differential pressure
- 0.1 bar
- Cold hydro test pressure
- 24 bar(g)
- End connection
- Screwed (NPT/BSPT/BSP)
- Installation
- Inlet and outlet horizontally in-line, body vertical for free bucket movement; bypass above trap level
- Body material
- Cast Iron
- Internals
- Stainless Steel (AISI 304)
- Valve seat & pin
- AISI 410/420 (Hardened)
Overview
The PT23 / PT23L is an inverted bucket steam trap in cast iron construction with an integral strainer and all stainless steel internals, best suited for equipment drains with medium to heavy condensate loads on intermittent operation. It works on the density difference between steam and water to give a cyclic discharge of accumulated condensate, with an induction-hardened valve and seat for prolonged continuous service and perfect shut-off with no steam loss. Rated to 16 bar(g) maximum allowable pressure and 220°C, the full internal kit is replaceable in-line without disturbing the piping connections. Supplied, sized and serviced for steam systems across Nepal.
Features & Benefits
- The inverted bucket mechanism works on the density difference between steam and water, which makes it mechanically simple and robust — there is no temperature-sensitive element to fail, so it tolerates water hammer and superheat better than thermostatic or thermodynamic traps.
- High condensate handling capacity even at low pressure means a physically smaller trap size can serve a given load, reducing cost and installation footprint compared to oversizing.
- Induction-hardened valve pin and seat concentrate wear resistance on the two highest-wear parts, extending service intervals in continuous prolonged operation.
- Integral strainer protects the valve mechanism from pipeline debris, which is the main cause of premature failure in bucket traps, and the screen is removable for regular cleaning.
- Perfect shut-off with no steam loss directly saves energy versus traps that leak live steam when worn, which matters over the operating life of a steam system where trap losses compound.
- Maintainable in-line without disturbing piping connections means the full internal kit (valve pin, seat, bracket, lever) can be replaced as a set after isolation, avoiding cutting the trap out of the line.
- The PT23L variant offers a lighter, lower-capacity option at DN20/DN25 for applications where the full PT23 capacity is not needed, giving a cheaper choice within the same product line.
Dimensions
| Model | Size (mm) | Size (inch) | A | B | C | D | Wt (kg) |
|---|---|---|---|---|---|---|---|
| PT23 | 15 | 1/2" | 120 | 100 | 156 | 71 | 3.20 |
| PT23 | 20 | 3/4" | 120 | 100 | 201 | 93 | 3.8 |
| PT23 | 25 | 1" | 180 | 160 | 255 | 137 | 9.2 |
| PT23L | 20 / 25 | 3/4", 1" | 120 | 100 | 156 | 71 | 3.70 |
- All dimensions are in mm, weights in kg.
- Dimensions shown here are for indicative purposes only. Please contact our representative for exact dimensions.
Continuous Discharge Capacity
| Discharge Capacity (kg/hr of hot condensate) — Differential Pressure (bar) | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Model | Orifice (mm) | 0.5 | 1.0 | 2.0 | 3.0 | 4.0 | 5.0 | 6.0 | 7.0 | 8.5 | 10.0 | 11.0 | 12.5 | 14.0 |
| PT23-15 / PT23L-20 / PT23L-25 | 2.5 | 40 | 80 | 125 | 140 | 180 | 190 | 210 | 225 | 245 | 260 | 280 | --- | --- |
| PT23-15 / PT23L-20 / PT23L-25 | 2.8 | 65 | 115 | 180 | 215 | 250 | 265 | 280 | 290 | 300 | --- | --- | --- | --- |
| PT23-15 / PT23L-20 / PT23L-25 | 3.2 | 110 | 160 | 210 | 250 | 280 | --- | --- | --- | --- | --- | --- | --- | --- |
| PT23-20 | 2.8 | 65 | 115 | 180 | 215 | 250 | 270 | 290 | 310 | 330 | 360 | 375 | 390 | --- |
| PT23-20 | 3.2 | 120 | 180 | 250 | 290 | 330 | 360 | 380 | 400 | 430 | --- | --- | --- | --- |
| PT23-20 | 4.0 | 160 | 225 | 310 | 350 | 410 | --- | --- | --- | --- | --- | --- | --- | --- |
| PT23-25 | 2.8 | 65 | 125 | 200 | 265 | 310 | 340 | 385 | 420 | 450 | 485 | 500 | 530 | 565 |
| PT23-25 | 4.0 | 190 | 330 | 490 | 600 | 660 | 725 | 785 | 830 | 860 | --- | --- | --- | --- |
| PT23-25 | 4.8 | 265 | 430 | 640 | 800 | 890 | --- | --- | --- | --- | --- | --- | --- | --- |
- Discharge capacity in kg/hr of hot condensate against differential pressure in bar.
- Select a capacity equal to or higher than the condensate load after applying a safety factor of 2 to 3. Oversizing is not recommended.
Materials of Construction
| Component | Material |
|---|---|
| Body | Cast Iron |
| Cover | Cast Iron |
| Bucket Assembly | AISI 304 with CS reinforcing ring where applicable |
| Lever Assembly | AISI 304 |
| Valve Seat (Hardened) | AISI 410/420 |
| Bracket | AISI 304 |
| Valve Pin (Hardened) | AISI 410/420 |
| Strainer Screen | AISI 304 (Perforated Sheet 0.8) |
| Strainer Cap | ASTM A743 Gr CA40 |
| Gasket (Cover) | Non CAF |
| Gasket (Strainer) | Non CAF |
| Bolt | High Tensile |
| Plug | Carbon Steel |
| Gasket (Plug) | Copper |
| Locating Tube | AISI 304 |


