A thermal separation of the working cylinder and the drive is necessary with measuring gas pumps, where the cylinder head is heated, or where pumped gases have a temperature above +130 degrees Celsius.
Here the cylinder head is separated from the motor or pump housing by spacers that have poor thermal conductivity. This enables the cylinder head to be heated up to a max. +240 degrees Celsius. The cylinder heads as well as other miscellaneous gas-conducting components can be chemically nickel-plated (-C-) to protect against alkalis and can be hard-coated (-E-) to protect against acids.
The coating is well proven with heated pumps: -E- aluminium, hard-coated. The heated and gas-conducting components are also available in VA. All data for the thermally separated pumps can be found under: PB-29, PB-32