The term pickling is used to describe acid treatments for the removal of rust formed by atmospheric corrosion and scale formed by heat treatment processes on steel. Essentially three acids or a combination are used to remove corrosion products from steel which are phosphoric, hydrochloric and sulphuric acids all of which will remove rust but only sulphuric and hydrochloric will remove scale.
Hydrochloric and Sulphuric Acid products are used for the removal of sludge and scale from pre-treatment plants and pipework systems. The best option is to use a specially formulated Sulphuric Acid based product at around 40C.
Hydrochloric Acid products should only be used at ambient temperatures.
They operate under the following conditions.
Normally used by spray or immersion at concentrations from ten to fifty percent by dilution with water at temperatures from ambient to 70°C.
Normally used by immersion at fifty percent by volume with water at ambient temperature.
Normally used by immersion at around ten percent dilution with water at temperatures around 60°C.
Products are available that will degrease and pickle in one operation and consist of the above acids alone or in combination blended with solvents and surfactants.
Acid cleaners are also used to etch aluminium prior to chrome and chrome free conversion coatings.
For further technical information on our product range please call Brian on 01204 495818 or email us to see which process meets your individual requirements.