Spirax Sarco BT6-B Balanced Pressure Steam Traps

Spirax Sarco BT6-B Balanced Pressure Steam Traps

The Spirax Sarco BT6-B sanitary balanced pressure thermostatic steam trap is designed to remove condensate from clean and pure steam applications with minimal condensate retention. Applications include sterile steam barriers, block and bleed installations, mains drainage and CIP / SIP of vessels and reactors and process lines.

Manufactured in 316L, the crevice free body design of the BT6-B incorporates a 15° angled seat to ensure full drainability. The body is self draining and available with a surface finish of up to 0.4 µm (16 micro-inch Ra).

The standard element is extremely sensitive to changes in condensate temperature and is designed to open with a minimum of sub-cooling, less than 3.6˚F (2°C) from steam saturation temperature at pressures below 36 psig (2.5 barg) for typical operating conditions. Exact operating performance may be affected by operating pressure, installation and ambient conditions.

A high capacity version is available for high condensate loads or where CIP/SIP fluids are used.

Each trap is individually packaged within a 'clean' environment with protective end caps and sealed in a protective plastic bag.

Surface Finish

All internal wetted surfaces have a finish of 0.6 µm (25 micro-inch Ra).


# Part Materials
1 Body Stainless Steel - ASTM A 276-87 Gr. 316L
2 Seat & Connection Stainless Steel - ASTM A 276-87 - Gr. 316L
3 Element Stainless Steel - AISI 316L
4 Clamp Stainless Steel - AISI 304L
5 Seal TPFE Jacketed Viton
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  • Mechanical and Electro-polishing to 0.375 µm (15 micro-inch Ra). 
  • PFTE encapsulated Viton seal can be supplied for dairy applications.
  • Special connections to suit most piping systems.

The BT6 is available with certification to EN 10204 3.1, typical internal surface finish certificates and typical certification of seals FDA/USP compliance. Note: All certification/inspection requirements must be stated at the time of order placement.


The BT6 fully complies with ASME BPE and the requirements of the European Pressure Equipment Directive 97 / 23 / EC. All seals comply with FDA CFR title 21, part 177, section 1550 and USP24 class VI.

Sizes and Pipe Connections
  • ½", ¾", 1" and 1½" sanitary clamp ends to ASME BPE.  Additional connections are available on request. Please contact STI.


ISO 1127 (Series 1) tube butt weld ends
  • 13.5 mm O/D x 1.6 mm wall thickness tube butt weld (DN8-I)
    17.2 mm O/D x 1.6 mm wall thickness tube butt weld (DN10-I)
    21.3 mm O/D x 1.6 mm wall thickness tube butt weld (DN15-I)
  • Note: Other connection options are available on request. Please Contact STI.
Pressure/Temperature Limits
  • The BT6 MUST NOT be used in this region.
  • The BT6 should not be used in this region as damage to the internals may occur.
  • Note:  For hygienic/sanitary clamp ends, the maximum pressure/temperature may be restricted by the gasket or sanitary clamp used.  Please Contact STI.



Body Design Conditions
PMA Maximum allowable pressure @ 140°C 10 bar g
TMA Maximum allowable temperature @ 9.2 bar g 177°C
N/A Minimum allowable temperature -254°C
PMO Maximum operating pressure for saturated steam service 6 bar g
TMO Maximum operating temperature @ 165°C 6 bar g
N/A Minimum operating temperature 0°C
N/A Designed for maximum cold hydraulic test pressure 15 bar g




Dimensions/Weights (approximate) in mm and kg
Size A B C D E Weight
1/2" 65 64 71.5 77 61 0.70
3/4" 65 64 71.5 77 61 0.71
1" 65 64 71.5 77 61 0.94
1-1/2" 65 64 71.5 77 61 0.86