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Stainless SteelSealed DesignUp to 30 bar g

Spirax Sarco SIB30 and SIB30H Sealed Inverted Bucket Steam Traps

Spirax Sarco SIB30 and SIB30H are stainless steel sealed inverted bucket steam traps suitable for 0.5 to 30 bar pressure differentials. Featuring a non-maintainable design.

Spirax Sarco SIB30 and SIB30H Sealed Inverted Bucket Steam Traps

Spirax Sarco SIB30 and SIB30H are all stainless steel sealed inverted bucket steam traps. They are supplied with a specified pressure change assembly depending on the required operating pressure differential. The traps are available with a range of seat sizes to suit pressure differentials between 0.5 to 30 bar (7.25 to 435 psi) and are fully compliant with the Pressure Equipment Directive (PED).

Spirax Sarco SIB30 sealed inverted bucket steam trap

Sizes and Pipe Connections

  • ½" and ¾" screwed BSP or NPT.
  • DN15 and DN20 socket weld ends (BS 3799).
  • DN15 and DN20 flanged ASME 150, ASME 300 and EN 1092 PN40 as standard. Alternative flanges are available on request, with JIS tables 20, 16 and 10 connections.

Limiting Conditions (ISO 6552)

Operating Region

The product must not be used outside the recommended maximum operating pressure region.

ParameterValue
PMA Maximum allowable pressure49 barg @ 38°C (711 psi g @ 100 °F)
TMA Maximum allowable temperature400°C @ 28 barg (752°F @ 406 psig)
Minimum allowable temperature-29°C (-20.2°F)
PMO Maximum operating pressure for saturated steam service30 bar g (435 psi g)
TMO Maximum operating temperature400°C @ 28 barg (752°F @ 406 psig)
Minimum operating temperature0°C (32°F)
Designed for a maximum cold hydraulic test pressure of75 bar g (1 087.5 psi g)

Maximum Differential Pressure (ΔPMX)

ΔPMX Maximum differential pressureSIB30 ModelSIB30H Model
30.0 bar (435 psi)SIB30/4SIB30H/5
20.0 bar (290 psi)SIB30/5SIB30H/6
12.0 bar (174 psi)SIB30/6SIB30H/7
8.5 bar (123 psi)SIB30/7SIB30H/8
5.0 bar (72 psi)-SIB30H/10
4.0 bar (58 psi)SIB30/8-
2.5 bar (36 psi)SIB30/10-
2.0 bar (29 psi)-SIB30H/12
1.5 bar (21 psi)SIB30/12-

Spirax Sarco SIB30 limiting conditions chart

Materials

No.PartMaterialStandard
1CoverStainless steelASTM A240 Gr. 304
2BodyStainless steelA182F304
2FlangesCarbon steelMat No. 1.0460 (C22.8)
3BucketStainless steelBS 1449 321 S 12
4Pivot pinStainless steelBS 970 304 S 15
5Valve seatStainless steelAISI440B
6ValveStainless steelAISI440B
7Valve leverStainless steelBS 1449 321 S 12
8Internal tubeStainless steelBS 3605 304 S 14

Spirax Sarco SIB30 materials diagram

Capacities

Trap Selection

A trap should be selected for the most appropriate working pressure differential and not on the basis of load. For example, a load of 80 kg/h at 7 bar differential should be handled with the SIB30/7 and not the SIB30/4.

Spirax Sarco SIB30 capacities chart low pressure

Spirax Sarco SIB30 capacities chart high pressure

Dimensions and Weights (approximate in mm and kg)

SIB30

SizeAA1BCDWeight (Scr/SW)Weight (Flg)
DN15 - ½"110150761241431.52.9
DN20 - ¾"110150761241431.52.9

SIB30H

SizeAA1BCDWeight (Scr/SW)Weight (Flg)
DN15 - ½"110150761591771.753.15
DN20 - ¾"110150761591771.753.15

Spirax Sarco SIB30 dimensions diagram

Installation and Maintenance

Safety Information

Safe operation requires proper installation and use. Ensure all pressure is safely isolated and vented before maintenance. The external surface may be very hot in normal use.

  • Positioning: The trap must be installed with the body upright so that the bucket is rising and falling vertically. It must be installed in a horizontal pipeline, below the drain point of the plant. A small drop leg should precede the trap - typically 150 mm (6").
  • Priming: When superheat conditions exist, the trap body may need to be primed with water prior to steam being turned on to avoid steam blowing through the trap.
  • Air Venting: Inverted bucket steam traps do not permit rapid release of air. A separate external air vent is required in parallel to vent air efficiently. Any bypass should be positioned above the trap.
  • Accessories: Where the trap discharges into a closed condensate return system or where there is a lift at the trap, a check valve should be fitted downstream of the trap. If installed on a superheated system, a non-return valve should be fitted on the inlet.
  • Welding: When welding the trap into the pipeline, this should be carried out by electric arc process. (The cover and flanges are TIG welded to the body during manufacture).
  • Maintenance: The SIB30 and SIB30H are factory set sealed steam traps. They are non-adjustable, non-maintainable, and require no maintenance; therefore, no spares are available.