HMA offers a range of quality absolute pressure gauges which are designed to reliably measure pressure. Our gauges come in various sizes and materials, such as monel, brass and stainless steel movements just to mention a few.

Rototherm DSU Diaphragm Seal Units
HMA Instrumentation recommends to fit a Rototherm DSU Diaphragm Seal Unit to a pressure gauge where the medium to be measured is highly viscous, contains suspended solids, or is potentially corrosive to the Bourdon tube. Rototherm DSU Diaphragm Seal Units from HMA Instrumentation are normally connected directly to the gauge. However, the connection may be also be affected by flexible capillary, which makes them ideal for remote pressure indication.

The flexible capillary can be used to facilitate the fitting of a Rototherm DSU Diaphragm Seal Unit from HMA Instrumentation in a surface- or panel-mounting location. The maximum capillary length is 5 m. Pressure is transmitted from the Rototherm DSU Diaphragm Seal Unit to the Bourdon tube by means of a suitable filling medium, the selection of which ensures compatibility with the process and process temperature.

If the Rototherm DSU Diaphragm Seal Unit from HMA Instrumentation is to be used on processes subject to temperature extremes, the temperature at the tipping point should be advised at the time of ordering. Rototherm DSU Diaphragm Seal Units from HMA Instrumentation can be fitted directly or remotely to the following Rototherm gauge types: SPG, RPG, DMC, SPGA, and turret gauges.

Rototherm Over Range Protectors
Rototerm Over Range Protectors from HMA Instrumentation is designed to protect gauges instruments, etc. from surges in pressure. These are available in shut-off ranges from 0.4 bar to 400 bar, with a maximum inlet pressure 600 bar.

A bonnet locking pin locks the bonnet safely to the body for added security. The maximum is temperature 80°C for the range of 0.4 to 2.5 bar and 110°C for the range 2.5 to 400 bar. Rototerm Over Range Protectors from HMA Instrumentation can also be supplied to NACE MR-01-75-Latest edition if required. The materials of construction range from 316 Grade stainless steel to Monel and brass.

Rototherm RPG Pressure Gauges
Rototherm RPG Pressure Gauges from HMA Instrumentation are available in 63 mm, 100 mm, and 150 mm dial sizes. In addition, dry and liquid-filled versions can be supplied, with either stainless Steel or Monel wetted parts.

The Rototherm RPG Pressure Gauges from HMA Instrumentation have a wide choice of mounting and process connection options. They comprise a range of economically-priced pressure gauges ideal for most industrial applications where accuracy and durability are mandatory.

A number of optional accessories are available for the Rototherm RPG Pressure Gauges from HMA Instrumentation, either as factory-fitted or retrofitted. These include diaphragm seal units, electrical contact head systems, syphons, over range protectors, snubbers, and additional pointers.