Products Service Applications Blog & Wiki Downloads About us Careers News & Events


Mechanical dial type gauging

Rugged mechanical vacuum gauges

  • In mechanical vacuum gauges the pressure is determined directly by recording the force acting on the surface of the diaphragm.
  • The readings obtained are independent of the type of gas and the pressure which is to be measured.
  • The pressure range for most mechanical dial gauges is approx. from 1000 mbar (atmospheric pressure, 750 Torr) to 1 mbar (0,75 Torr). 


The inner part of the BOURDONVAC is a Bourdon tube, which is bent into a circular arc and is connected to the vacuum system. 

Due to the effect of the external atmospheric pressure, the end of the tube bends more or less during the evacuation process. This actuates the pointer arrangement which is attached to this point. The corresponding pressure can be read off on a linear scale.

With BOURDONVAC gauges it is possible to roughly determine pressures from atmosphere to 1mbar/torr.

As the mechanism is exposed to local atmospheric pressure, it can be affected by fluctuations in atmospheric pressure.

Those gauges are designed for rough pressure measurement in harsh environments:

  • Great process compatibility due to its stainless-steel measuring cell,
  • Resistance against vibrations
  • IP54 rating
Portable and Mechanical Gauging


CAPSULE gauges operate with a diaphragm connected to a dial.

They contain a hermetically sealed, evacuated and thin-walled diaphragm capsule located within the instrument. As the vacuum pressure reduces the capsule bulges. This movement is transferred via a system of levers to a pointer and the pressure can be read off on a linear scale. 

As the measuring cell is hermetically sealed against the outside environment, it is not affected by changes in atmospheric pressure, making it more reliable at pressures below 10 mbar/torr.

  • Insensitive to vibrations
  • Due to the measuring system being open to the vacuum environment it is less compatible with corrosive media. 

As CAPSULE gauges are better to read lower pressures, we offer it with two full scales:

  • 1000 to 1mbar (750 to 0.75 torr)
  • 100 to 1 mbar (75 to 0.75 torr) with the later giving better resolution at the lower pressures.

It also comes with either:

  • a DN 16 ISO-KF flange to connect directly to a vacuum system
  • a 10 mm diameter hose nozzle with integrated isolation valve for panel mounting and use on packing machines.
Portable and Mechanical Gauging


Where the BOURDONVAC is great with corrosive media, but affected by atmospheric pressure, and the capsule gauge is less capable with corrosive media, but not affected by ambient pressure, the DIAVAC DV 1000 combines the best features of both into a single gauge. 

Inside the case is a diaphragm capable of absolute pressure measurements, and a sealed and evacuated vacuum chamber is separated by a diaphragm from the vacuum pressure to be measured. This serves as the reference quantity.

With increasing evacuation, the difference between the pressure which is to be measured and the pressure within the reference chamber becomes less, causing the diaphragm to flex. This flexure may be transferred by mechanical means like a lever, for example, to a pointer scale.

The DIAVAC DV 1000 is made for rough pressure measurement in corrosive environments as the sensitive parts are in a sealed reference volume and the materials exposed to vacuum in the sensing cell are Stainless steel/FPM.

To increase the accuracy of the gauge: each scale is individually calibrated for optimum performance.

Portable and Mechanical Gauging
  • Readout independent of the type of gas and changes in atmospheric pressure  
  • Stainless steel diaphragm (BOURDONVAC and DIAVAC) for excellent compatibility with most media  
  • Laser welding technology for high precision diaphragm mount (DIAVAC) 
  • Rugged table-top housing, can be freely mounted above the flange connection; also for panel mounting (DIAVAC and Capsule gauge) 
  • Measurement chamber can be easily cleaned owing to the detachable measurement flange (DIAVAC) 
  • Large and clear displays for easy final checks of vacuum levels 
Contact Leybold

Let's talk

We focus on customer proximity. Contact us for all your questions.