The Levelstate Type 501 Water Column from HMA INSTRUMENTATION is a low-pressure water column manufactured from ASTM A105 carbon steel extrusion. The section was designed by Levelstate specifically for the application. The rating is 150 bar @ 341°C, and pressure-tested to 225 bar @ ambient temperature.

The probe seats are machined into the thick wall of the extrusion at custom spacing as determined by the customer. Probes are staggered odds on one side and evens on the other for the greatest resolutions over smaller distances. Probes are secured by means of a screw thread, and are sealed with Metaflex gaskets. The minimum probe spacing is 25 mm. Steam and water connection stubs are provided with either socket or butt weld finishes. The top of the column incorporates an eye bolt for hanging purposes. However, this can be substituted for a vent connection.