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GESTRA VK – Flow Indicator / Vaposcope for Steam Traps

The GESTRA VK is a dual-sided flow indicator designed for monitoring flow in steam and condensate lines. It is installed upstream of the steam trap, allowing operators to identify normal condensate discharge, condensate backup, or live steam leakage. It features no moving parts and does not function as a flow meter.

Versions and Connections

• VK 14: PN16, DN15–DN50, flanges EN 1092-1 B1 PN16
• VK 16: PN40 or ASME Class 150/300, DN15–DN50
• VK16 Connections: EN / ASME flanges, ISO 228-1 G or NPT threads per ASME B16.11, socket-weld per DIN EN 12760 / ASME B16.11 Class 3000
• Glass: MAXOS® borosilicate glass DIN 7080
• Glass Sealing: graphite / CrNi

Materials and Operating Limits

VK14 uses body 5.1301 / EN-GJL-250, suitable for fluids up to pH 9. VK16 uses body 1.0460 and insert 1.0619, with a pH limit of 10. VK14 operates up to 16 bar at lower temperatures, reducing to 9.6 bar at 280 °C. VK16 reaches up to 40 bar, reducing to 27.6 bar at 300 °C.

Applications

Used in:

• steam trap operation monitoring
• condensate lines before return
• condensate banking-up detection
• live steam leakage diagnosis
• auxiliary networks for Group 2 fluids, with chemical compatibility checks

Installation and Maintenance

Install upstream of the steam trap, following flow arrow and baffle position instructions. Piping should not impose stress or torque on the body. Manual recommends periodic visual inspection for leaks and deposits, and replacement of worn components.

FAQ

Does it accept an actuator?
No. It is a passive flow indicator.

What should be specified in the order?
Type VK14 or VK16, DN/NPS, connection, operating pressure, operating temperature, fluid pH, and requirement for EN 10204 certificate.