Watson McDaniel Authorized Distributor

Watson McDaniel FTT Series Float & Thermostatic Steam Trap, Ductile Iron Body, 250 PSIG PMO, In-Line Pipe, 1-1/2", 2" NPT

SKU: WM-FTT-NPT-250
Made in the United States
Starting at $2,404.99

Select a Size to Order This page shows the full valve series. Choose a specific pipe size below to view pricing and add to cart.

Available Sizes
Sizes1/2" - 2"
PMO Max. Operating Pressure250 PSIG
Body MaterialDuctile Iron
ConnectionsNPT, 150# FLG (1" - 2")
TMO Max. Operating TemperatureSaturated Steam Temperature
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Technical Specifications

General

ModelFTT - Ductile Iron
Sizes1/2" - 2"
BrandWatson McDaniel
Manufacturer Part #WM-FTT-NPT-250
Country of OriginMade in the United States

Materials & Construction

Body MaterialDuctile Iron

Performance

PMO Max. Operating Pressure250 PSIG
TMO Max. Operating TemperatureSaturated Steam Temperature
PMA Max. Allowable Pressure350 PSIG up to 450°F
TMA Max. Allowable Temperature450°F @ 300 PSIG

Connections

ConnectionsNPT, 150# FLG (1" - 2")

Overview

Watson McDaniel FTT Series Float & Thermostatic Steam Trap - NPT (250 PSIG PMO)

Features:

  • Ductile Iron has a higher pressure and temperature rating and is more resistant to shock loads than cast Iron
  • All stainless steel internals with hardened seat and wear parts
  • In-line repairability is simplified by having all internals attached to the cover
  • Welded stainless steel thermostatic air vent resists shock from waterhammer. Live orifice air vent is available for superheated applications
  • Excellent air handling capability allows air to be discharged rapidly so steam can enter the system quickly during start-up
  • F&T traps discharge condensate immediately as it is formed (no condensate will back up into the system)

Options & Features (See Specification Sheet For Full List):

FTT Series - Ductile Iron Body

FTT-Series Float and Thermostatic Steam Traps have Ductile Iron Bodies ••• In-Line Pipe Connections ••• 300 psig Operating Pressures ••• All stainless Steel Internals. Typically used on steam process applications such as unit heaters, pressing machines, heat exchangers, steam coils. Contain a welded stainless steel thermostatic air vent for rapid air removal on system start-up, important on process applications.

DRIP, PROCESS: FTT Series steam traps with in-line pipe connections are used for the removal of condensate and air in HVAC and industrial process applications such as unit heaters, water heaters, pressing machines, heat exchangers and coils. They contain a high-quality welded stainless steel thermostatic air vent and stainless seat and mechanism. F&T traps have excellent air handling capability, making them a better choice than Inverted Bucket traps for most process applications. For drip applications, such as draining steam mains and steam supply lines, use 1/2" or 3/4" sizes.

How It Works

Float and thermostatic traps contain a float and seat mechanism with a separate thermostatic element which work together to remove both condensate and air from the steam system. The float, which is attached to a valve, rises and opens the valve when condensate enters the trap. This allows the condensate to discharge. Air is discharged through the thermostatic air vent to the outlet side of the trap. Steam entering the trap causes the thermostatic element to expand, closing the air vent and trapping the steam.

Selection / Sizing / Capacities

The PMO (maximum operating pressure) rating of model selected must meet or exceed the maximum steam pressure or the trap may not open. For example; the FTT-145 has a PMO of 145 psi. Condensate capacity (lbs/hr) of the trap is based on the differential pressure across the trap. For drip applications, a 1/2" FTT size is generally sufficient to exceed warm-up loads with a 2X safety factor. The condensate loads (lbs/hr) for process applications are normally calculated at the maximum steam pressure; then an appropriate safety margin is applied in order to select the trap with sufficient capacity when operating at lower steam pressures. reference full explanation of Safety Load Factors in Steam Traps Introduction section.

When a temperature control valve is regulating flow to the process equipment, it is recommended to select a trap with a PMO that will exceed the inlet steam pressure to the control valve.

For Example:

  • Process application has a maximum steam inlet pressure of 100 psi, a maximum condensate load of 2,500 lbs/hr and is discharging to a condensate return line with a possible back pressure of 25 psig. ΔP = 100-25 = 75 PSI

To select trap:

  • If the Safety Load Factor is chosen to be 2X max capacity at max differential pressure, then Trap should be selected based on 5,000 lbs/hr (2,500 x 2 = 5,000) at 75 PSI differential pressure with a PMO in excess of 100 PSIG

Selection:

  • FTT-145-16-N, PMO=145 PSIG, 11/2" NPT with a condensate capacity of 9,600 lbs/hr at 75 PSI differential pressure.

Connection Code: N=NPT, F150 = 150# FLG 1/2" & 3/4" available in NPT only. PMO = Max Operating Pressure.

Options

  • Live orifice air vent for superheated steam applications.
  • NPT Connection for freeze protection.

Installation & Maintenance

The trap must be installed upright and level for the float mechanism to operate properly. All internal components can be replaced with the trap body remaining in-line. Repair kits include thermostatic air vent, float, valve seat and disc, and gaskets. The standard thermostatic air vent can be damaged by superheat; therefore, in applications with superheated steam, the thermostatic air vent should be replaced with a special “live orifice" air vent.