TLV FP46UN QuickTrap Thermodynamic Disc Steam Trap

A replaceable disc steam trap for steam mains, tracers and coils

The TLV FP46UN QuickTrap is a universal thermodynamic disc steam trap with thermostatic air venting, sold as a DN 15 (15 mm) unit with a cast stainless steel body. Its selling point is installation: a union connection, a two-bolt flange connector and a replaceable trap unit with a module valve seat let a worn trap be changed in minutes without disturbing the piping. The universal flange and unions also allow the trap to be turned to the correct attitude whatever the pipeline layout. TLV recommends this style of trap for steam mains, tracer lines and coils.

Technical specifications

Why the disc and QuickTrap design matter

TLV describes its PowerDyne disc traps as being developed to reduce life cycle cost across purchase, installation, maintenance and steam loss. The lapped disc gives a steam-tight seal without air binding, the working surfaces are hardened stainless steel, and air jacketing reduces cycling and extends life. A bimetal ring opens the valve while the trap is cold, so air and cold condensate leave quickly at start-up. Related PowerDyne models listed by TLV include the P21S (2.1 MPaG), the P46S and the P46SRN (both 4.6 MPaG), all with screwed connections and a 425 °C operating temperature limit.

Selection and documents

Select the trap from the inlet pressure, the back pressure (not above 80 percent of inlet) and the condensate load on the discharge capacity chart in the specification sheet, and apply a safety factor of at least 2 as the sheet recommends. TLV states that the product must not be used outside its specification range and that local regulations may restrict use below the quoted limits. For a larger float-type alternative on the same site, browse the steam trap range, which includes the Yarway 751/761 repairable drip and tracer trap. The attached TLV specification sheet gives the pressure-temperature graph, parts list and dimensions. Send the steam pressure, back pressure, load and connection type with your enquiry, and confirm the final model code against current TLV documents before ordering.

How the TLV FP46UN works

The FP46UN is a thermodynamic disc steam trap. Steam and condensate enter below the disc. Cold condensate and air push the disc up and leave through the outlet. When hot steam arrives, it flows fast under the disc, the pressure above the disc rises and the disc closes on the seat. Heat loss from the cover then lowers the pressure above the disc, and the disc lifts again to discharge condensate. A bimetal ring opens the valve while the trap is cold, so air leaves quickly at start-up.

Where the TLV FP46UN is used

• Steam mains and drip legs
• Steam tracer lines
• Heating coils
• Process equipment that needs a quick trap change
• Plants where space for piping is tight

Selection checklist for the FP46UN

• Size of 15 mm
• Maximum operating pressure of 4.6 MPaG
• Minimum operating pressure of 0.03 MPaG
• Maximum operating temperature of 400 degrees C
• Back pressure of up to 80 percent of the inlet pressure
• Union connection or pipe end version
• Cast stainless steel body
• Screen inside the connector

Installation, commissioning and maintenance notes

Fit the connector in the line and attach the trap unit with the two-bolt flange. The universal flange lets the trap be turned to the correct attitude. Check the flow direction and fit the gaskets supplied. After start-up, test the trap and look for steam loss. To change the trap, remove the two bolts and replace the trap unit without disturbing the piping.

Requesting a quotation for the TLV FP46UN

Please send the model, the connection type, the steam pressure and the quantity needed. Seven Star LLC serves industrial customers in Oman and the GCC and replies with a quotation based on the information provided.

FP46UN materials

The body and connector are cast stainless steel to ASTM A351 CF8, and the disc and holder ring are hardened stainless steel.

FP46UN QuickTrap design

The union, the two-bolt connector and the replaceable trap unit with a module valve seat allow a worn trap to be changed in minutes.

FP46UN size and weight

The union version is 85 mm long and weighs 1.8 kg, and the pipe end version is 188 mm long and weighs 2.2 kg.

FP46UN pressure limits

The maximum allowable pressure is 6.6 MPaG at 40 degrees C.

Steam trap records for FP46UN

Keep the trap tag, the location and the test results with the steam system file.

Choosing the right FP46UN connection

Choose the union version for threaded lines and the pipe end version where the trap is welded into the line.