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Cast SteelThree-Point SeatingThermostatic Air VentingInline Repairable

TLV SH6NL Free Float Steam Trap

TLV SH6NL inline repairable cast steel free float steam trap with three-point seating and thermostatic air venting for superheated or high-pressure steam mains.

TLV SH6NL Free Float Steam Trap

TLV SH6NL is an inline repairable cast steel free float steam trap with tight shut-off, designed for the drainage of superheated or high-pressure steam mains and turbines. It features a thermostatic air vent and a three-point seating design to ensure a steam-tight seal even under no-load conditions.

Note on Product Family

While this page focuses on the SH6NL model, the provided maintenance and troubleshooting instructions also apply to the broader SH series (SH3NL, SH5NL, SH5NH, SH6NH, SH5VL) as detailed in the shared instruction manual.

Features

  1. Self-modulating free float provides continuous, smooth, low velocity condensate discharge as loads vary.
  2. Precision-ground float, constant water seal and three-point seating design ensure a steam tight seal, even under no-load conditions.
  3. Only one moving part, the free float, prevents concentrated wear and provides long maintenance-free service life.
  4. Thermostatic air venting with bimetal strip allows fast start-up.
  5. High rating against hydraulic shock offers excellent resistance of the float to water hammer.
  6. Built-in screen with large surface area ensures extended trouble-free operation.
  7. Easy, inline access to internal parts simplifies cleaning and reduces maintenance costs.

Specifications

ModelSH6NL
ConnectionSocket Welded, Flanged
SizeDN 25, 40, 50
Orifice No.14, 32, 46, 65
Maximum Operating Pressure (PMO)14, 32, 46, 65 barg
Maximum Differential Pressure (ΔPMX)14, 32, 46, 65 bar
Maximum Operating Temperature (TMO)425 °C (Socket Welded) / 400* / 425 °C (Flanged)

PRESSURE SHELL DESIGN CONDITIONS (NOT OPERATING CONDITIONS):

  • Maximum Allowable Pressure (PMA): 65 barg
  • Maximum Allowable Temperature (TMA): 400* / 425 °C * With PN Flange

WARNING

To avoid abnormal operation, accidents or serious injury, DO NOT use this product outside of the specification range. Local regulations may restrict the use of this product to below the conditions quoted.

Materials

No.DescriptionMaterialDIN*ASTM/AISI*
1BodyCast Steel A216 Gr.WCB1.0619
2CoverCast Steel A216 Gr.WCB1.0619
3FFloatStainless Steel SUS316L1.4404AISI316L
4ROrifice
5MROrifice GasketGraphite/Stainl. Steel SUS316L-/1.4404-/AISI316L
6RAir Vent StripBimetal
7RScrew & Spring WasherStainless Steel SUS3041.4301AISI304
8MRCover GasketGraphite/Stainl. Steel SUS316L-/1.4404-/AISI316L
9Cover BoltAlloy Steel SNB71.7225A193 Gr.B7
10Cover NutCarbon Steel S45C1.0503AISI1045
11RScreenStainless Steel SUS4301.4016AISI430
12Screen HolderCast Stainless Steel A351 Gr.CF81.4312
13MRScreen Holder GasketSoft Iron SUYP1.1121AISI1010
14Orifice PlugCast Stainless Steel A351 Gr.CF81.4312
15MROrifice Plug GasketSoft Iron SUYP1.1121AISI1010
16Socket**Carbon Steel A1051.0460
17Flange***Carbon Steel A105/Cast Steel A216 Gr.WCB1.0460/1.0619
18NameplateStainless Steel SUS3041.4301AISI304

* Equivalent materials. *** Material depends on flange specifications. Replacement kits available: (M) maintenance parts, (R) repair parts, (F) float.

Dimensions

Socket Welded

TLV SH6NL socket welded dimensions diagram

SizeLH1*W*φBφDφChWeight (kg)
251781852601804833.91421
401781852601806448.81422
5017818526018076.561.21723

* ASME B16.11-2005, other standards available. ** Approx.

Flanged

TLV SH6NL flanged dimensions diagram

DNL (DIN PN25/40)L (DIN PN63/100)L (ASME 150, 300, 600RF)L (ASME 900RF)H1*W*φBWeight** (kg)
2516023022223218526018026
4023032027027018526018030
5023032023231018526018038

Other standards available, but length and weight may vary. * Approx. ** Weight is for ASME Class 900 RF.

Discharge Capacity

TLV SH6NL discharge capacity graph

  1. Line numbers within the graph refer to orifice numbers.
  2. Differential pressure is the difference between the inlet and outlet pressure of the trap.
  3. Capacities are based on continuous discharge of condensate 6 ℃ below steam temperature.
  4. Recommended safety factor: at least 1.5.

Configuration

TLV SH6NL cross-section configuration diagram

No.DescriptionNo.Description
1Body10Cover Nut
2Cover11Screen
3Float12Screen Holder
4Orifice13Screen Holder Gasket
5Orifice Gasket14Flange / Socket
6Air Vent Strip15Nameplate
7Screw with Spring Washer16Orifice Plug
8Cover Gasket17Orifice Plug Gasket
9Cover Bolt18UP-Sticker (SH5VL)

Proper Installation

DANGER

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

  • 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.
  • Use hoisting equipment for heavy objects.
  • 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 trap within the allowable inclination, as shown below. 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 downward 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 0.8 meters (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.
  8. TLV recommends unions to facilitate connection and disconnection of the screwed version.

Allowable Inclination

TLV SH6NL allowable installation inclination

The face of the screen holder perpendicular to the ground, and the inlet and outlet horizontal to the ground.

IMPORTANT! (For screwed connection)

To prevent rotation due to vibration secure trap in position by supporting the body at the point marked ▲.

Piping Arrangement

RequirementCorrectIncorrect
Install a catchpot with the proper diameter.Correct diameterDiameter is too small.
Make sure the flow of condensate is not obstructed.Unobstructed flowDiameter is too small and inlet protrudes into pipe.
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.Connected above baseRust and scale flow into the trap with the condensate.
When installing on the blind end, make sure nothing obstructs the flow of condensate.Unobstructed flowCondensate collects in the 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 a temperature drop in the equipment, poor product quality or losses due to steam leakage.

TLV SH6NL exploded view of components

Parts Inspection Procedure

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

Tightening Torque and Distance Across Flats (SH Series)

ModelCover Nut (N·m / mm)Orifice (N·m / mm)Orifice Plug (N·m / mm)Screen Holder (N·m / mm)Screw (N·m / mm)
SH3NL60 / 1760 / 17200 / 38200 / 380.3 / +
SH5NL120 / 2280 / 19200 / 38200 / 380.3 / +
SH6NL130 / 22200 / 30400 / 50200 / 380.3 / +
SH5NH150 / 22100 / 21200 / 38200 / 380.3 / +
SH6NH370 / 30220 / 30400 / 50200 / 380.3 / +
SH5VL120 / 2280 / 19300 / 38200 / 380.3 / +

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. If the trap does not discharge to atmosphere, use diagnostic equipment such as TLV TrapMan.

StatusDescription
NormalCondensate 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.
BlockedNo condensate is discharged. The trap is quiet and makes no noise, and the surface temperature of the trap is low.
BlowingLive steam continually flows from the outlet and there is a continuous metallic sound.
Steam LeakageLive steam is discharged through the trap outlet together with the condensate and there is a high-pitched sound.

TLV SH6NL visual operational check for flash steam and live steam leakage

Troubleshooting

ProblemCauseRemedy
No condensate is discharged (blocked) or discharge is poorFloat is damaged or filled with condensateReplace with new float
The float is sticking to the orificeClean
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
Flow exceeds trap's rated capacityCheck specifications and reselect trap suitable for actual flow
The trap operating pressure exceeds the maximum specified pressure, or there is insufficient differential pressureCompare specifications and actual operating conditions
Steam is discharged or leaks from the trap outlet (blowing)Rust and scale have accumulated around the orifice or under the floatClean
Scratches on the orificeReplace with a new 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 air vent strip is damagedReplace with a new air vent strip
Steam leaks from a place other than the trap outletDeterioration of or damage to gasketsReplace with new gaskets
Improper tightening torque on cover nuts was usedTighten to the proper torque
Float is frequently damagedWater hammer occursExamine the piping for problems that can cause water hammer