Hydrochloric acid containing metal dust and heated to a temperature of 98°C is fed to a concentration analyzer in order to manage the concentration of the hydrochloric acid during the acid cleaning process.
An air-driven diaphragm pump was used, which posed the following problems.

• The diaphragm is damaged very quickly due to the high-temperature hydrochloric acid that contains metal dust, so frequent diaphragm replacements are required.
• Measured values were not stable due to the pulsation of the pump.

To prevent diaphragm deterioration due to wear and high temperatures, T-branch remote head specifications, in which the hydrochloric acid and the diaphragm do not come into direct contact, were used.
Also, heat-radiation fin specifications were used to prevent the high temperatures from being conveyed to the drive part of the pump.

• This made it possible to use the diaphragm for long periods of time, reducing the frequency of maintenance.
• Because a constant amount can be supplied without pulsation, it became possible to obtain stable measured results.