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Ductile Cast IronMax 22 bargMax 220 °CFree Float

TLV SJ7FNB / SJ7FVB Free Float Steam Trap

TLV SJ7FNB and SJ7FVB free float steam traps with thermostatic bimetal air vent. Features ductile cast iron body, up to 22 barg operating pressure, and 220 °C max temperature.

TLV SJ7FNB / SJ7FVB Free Float Steam Trap

TLV SJ7FNB and SJ7FVB are reliable and durable free float steam traps with tight shut-off for use on medium-size process equipment. Models are available for horizontal (SJ7FNB) or vertical (SJ7FVB) piping installation.

Features

  • Self-modulating free float provides continuous, smooth, low velocity condensate discharge as process loads vary.
  • Precision-ground float, constant water seal and three-point seating design ensure a steam-tight seal, even under no-load conditions.
  • Thermostatic bimetal air vent valve vents air automatically for rapid startup.
  • Built-in screen with large surface area ensures extended trouble-free operation.
  • Easy, inline access to internal parts simplifies cleaning and reduces maintenance costs.

Specifications

ModelSJ7FNBSJ7FVB
InstallationHorizontalVertical
ConnectionFlangedFlanged
SizeDN 40, 50DN 40, 50
Orifice No.2, 5, 9, 14, 222, 5, 9, 14, 22
Maximum Operating Pressure (PMO)22 barg22 barg
Maximum Differential Pressure (ΔPMX)22 bar22 bar
Maximum Operating Temperature (TMO)220 °C220 °C

WARNING

To avoid malfunctions, product damage, accidents or serious injury, install properly and DO NOT use this product outside the specification range. Local regulations may restrict the use of this product to below the conditions quoted.

Materials

TLV SJ7FNB / SJ7FVB TLV SJ7FNB cross sectionTLV SJ7FNB / SJ7FVB TLV SJ7FVB cross section

No.DescriptionMaterialDINASTM/AISI
1BodyDuctile Cast Iron GGG40.3 / EN 5.31030.7043A395 Gr.60-40-18
2CoverDuctile Cast Iron GGG40.3 / EN 5.31030.7043A395 Gr.60-40-18
3FloatStainless Steel SUS316L1.4404AISI 316L
4Orifice---
5Orifice GasketFluorine Resin PTFEPTFEPTFE
6ScreenStainless Steel SUS3041.4301AISI 304
7Element Cover GasketFluorine Resin PTFEPTFEPTFE
8Cover GasketFluorine Resin PTFEPTFEPTFE
9Cover BoltCarbon Steel S45C1.0503AISI 1045
10Orifice Plug (SJ7FNB)Cast Stainless Steel A351 Gr.CF81.4312-
11Element CoverCast Stainless Steel A351 Gr.CF81.4312-
12Screen HolderCast Stainless Steel A351 Gr.CF81.4312-
13Screen Holder GasketSoft Iron SUYP1.1121AISI 1010
14Main ScreenStainless Steel SUS4301.4016AISI 430
15NameplateStainless Steel SUS3041.4301AISI 304
16PlugCarbon Steel SS4001.0037A6
17Element GuideStainless Steel SUS3041.4301AISI 304
18Air Vent Valve Seat---
19Bimetal---
20Snap RingStainless Steel SUS3041.4301AISI 304
21Air Vent Valve---
22Snap RingStainless Steel SUS3041.4301AISI 304
23Orifice Plug Gasket (SJ7FNB)Soft Iron SUYP1.1121AISI 1010

Dimensions

SJ7FNB Flanged (Horizontal)

TLV SJ7FNB / SJ7FVB TLV SJ7FNB dimensions

DNL (DIN 2501 PN25/40)H1WBWeight (kg)
4023031535020526
5023031535020528

SJ7FVB Flanged (Vertical)

TLV SJ7FNB / SJ7FVB TLV SJ7FVB dimensions

DNL (DIN 2501 PN25/40)W1B1Weight (kg)
4023030520522
5023030520523

Discharge Capacity

TLV SJ7FNB / SJ7FVB discharge capacity graph

  1. Line numbers within the graph are orifice numbers.
  2. Differential pressure is the difference between the inlet and outlet pressure of the trap.
  3. Recommended safety factor: at least 1.5.

DANGER

DO NOT use this product under conditions that exceed maximum differential pressure, as condensate backup will occur!

Configuration

SJ7FNB

TLV SJ7FNB / SJ7FVB TLV SJ7FNB configuration

SJ7FVB

TLV SJ7FNB / SJ7FVB TLV SJ7FVB configuration

Proper Installation

  • Installation, inspection, maintenance, repairs, disassembly, adjustment and valve opening/closing should be carried out only by trained maintenance personnel.
  • Take measures to prevent people from coming into direct contact with product outlets.
  • Install for use under conditions in which no freeze-up will occur.
  • Install for use under conditions in which no water hammer will occur.
  1. Before installation, be sure to remove all protective seals.
  2. Install the steam trap within the allowable inclination. Also make sure that the arrow mark on the body corresponds with the direction of flow.
  3. Before installing the trap, blow out the inlet piping to remove all dirt and oil.
  4. Install the trap in the lowest part of the pipeline or equipment so the condensate flows naturally into the trap by gravity. The inlet pipe should be as short and have as few bends as possible.
  5. Support the pipes properly within 800 mm (2.5 ft) on either side of the trap.
  6. Install a bypass valve to discharge condensate, and inlet and outlet valves to isolate the trap in the event of trap failure or when performing maintenance.
  7. Install a check valve at the trap outlet whenever more than one trap is connected to the condensate collection pipeline.

TLV SJ7FNB / SJ7FVB TLV SJ7FNB horizontal installationTLV SJ7FNB / SJ7FVB allowable inclinationTLV SJ7FNB / SJ7FVB TLV SJ7FVB vertical installation

Piping Arrangement

Check to make sure that the pipes connected to the trap have been installed properly.

  1. Is the pipe diameter suitable?
  2. Has the trap been installed within the allowable inclination and with the arrow on the body pointing in the direction of flow?
  3. Has sufficient space been secured for maintenance?
  4. Have maintenance valves been installed at the inlet and outlet? If the outlet is subject to back pressure, has a check valve been installed?
  5. Is the inlet pipe as short as possible, with as few bends as possible, and installed so that the condensate will flow naturally down into the trap?
  6. To prevent rust and scale from flowing into the trap, connect the inlet pipe 25 - 50 mm (1 - 2 in) above the base of the T-pipe.

Inspection and Maintenance

Operational inspections should be performed at least twice per year, or as called for by trap operating conditions. Steam trap failure may result in temperature drop in the equipment, poor product quality or losses due to steam leakage.

DANGER

NEVER apply direct heat to the float. The float may explode due to increased internal pressure, causing accidents leading to serious injury or property and equipment damage.

  • Before attempting to open the trap, close the inlet and outlet isolation valves and wait until the trap has cooled completely. Failure to do so may result in burns.
  • Be sure to use the proper components and NEVER attempt to modify the product.

Parts Inspection Procedure

PartInspection Item
Body, CoverCheck inside for damage, dirt, grease, oil film, rust or scale
GasketsCheck for warping or damage
Bimetal UnitCheck for damage
ScreenCheck for clogging, corrosion or damage
FloatCheck for deformation, damage, oil film or water inside
Air Vent Valve Seat, OrificeCheck for rust, scale, oil film, wear or damage

Tightening Torques and Distance Across Flats

PartTorque (N·m)Distance Across Flats (mm)
Cover Bolt10024
Orifice12030
Screen Holder40050
Drain Plug3012
Element Cover14032
Air Vent Valve Seat3519
Orifice Plug40050

(Note: 1 N·m ≈ 10 kg·cm)

Operational Check

A visual inspection can be carried out to aid in determining the necessity for immediate maintenance or repair, if the trap is open to atmosphere.

  • Normal: Condensate is discharged continuously with flash steam and the sound of flow can be heard. If there is very little condensate, there is almost no sound of flow.
  • Blocked: No condensate is discharged. The trap is quiet and makes no noise, and the surface temperature of the trap is low.
  • Blowing: Live steam continually flows from the outlet and there is a continuous metallic sound.
  • Steam Leakage: Live steam is discharged through the trap outlet together with the condensate and there is a high-pitched sound.

TLV SJ7FNB / SJ7FVB operational check flash steam vs live steam leakage

Troubleshooting

ProblemCauseRemedy
No condensate is discharged or discharge is poorFloat is damaged or filled with condensateReplace the float
Orifice, screen or piping is clogged with rust or scaleClean
Steam-locking has occurredBlowdown through the bypass or close the trap inlet valve and allow the trap to cool
Bimetal unit is damagedReplace the bimetal unit
The trap operating pressure exceeds the maximum specified pressure, or there is insufficient pressure differentialCompare specifications and actual operating conditions
Steam is discharged or leaks from the trap outlet (blowing) (steam leakage)Rust and scale have accumulated around the orifice or under the floatClean
Orifice is damagedReplace the orifice
Float is deformed or coated with scaleClean or replace the float
Trap is installed above the maximum allowable inclination angleCorrect the installation
Vibration of trap occursLengthen inlet piping, then fasten it securely
The bimetal unit is damaged, or clogged with rust or scaleClean or replace the bimetal unit
Steam leaks from a place other than the trap outletDeterioration of or damage to gasketsReplace with new gaskets
Leakage from eroded cavities of body or coverReplace the trap
Improper tightening torque for cover was usedTighten to the proper torque
Float is frequently damagedWater hammer occursExamine the piping for problems that can cause water hammer