The acid-base test of DINSEN cast iron pipe (also called SML pipe) is often used to evaluate its corrosion resistance, especially in acidic and alkaline environments. Cast iron drainage pipes are widely used in water supply, drainage and industrial piping systems due to their excellent mechanical properties and corrosion resistance. The following are the general steps and precautions for conducting acid-base tests on SML pipes:
Purpose of the experiment
Evaluate the corrosion resistance of ductile iron pipes in acidic and alkaline environments.
Determine its chemical stability under different pH conditions.
Provide a reference for material selection in practical applications.
Experimental materials
Cast iron pipe samples (cut into appropriate sizes).
Acidic solutions (such as dilute sulfuric acid, dilute hydrochloric acid, pH value can be adjusted as needed).
Alkaline solutions (such as sodium hydroxide solution, pH value can be adjusted as needed).
Containers (acid-resistant glass or plastic containers).
Measuring tools (pH meter, electronic balance, vernier caliper, etc.).
Corrosion rate measurement equipment (such as drying oven and balance required for weight loss method).
Protective equipment (gloves, goggles, lab coats, etc.).
Experimental steps
Sample preparation:
Cut the SML pipe sample and ensure that the surface is clean and free of oil.
Measure and record the initial size and weight of the sample.
Prepare the solution:
Prepare the acidic solution and alkaline solution of the required pH value.
Use a pH meter to calibrate the pH of the solution.
Immersion experiment:
Immerse the DINSEN cast iron pipe sample in the acidic solution and the alkaline solution respectively.
Make sure that the sample is completely immersed and record the immersion time (such as 24 hours, 7 days, 30 days, etc.).
Observation and recording:
Observe the surface changes of the sample regularly (such as corrosion, discoloration, precipitation, etc.).
Record the color change of the solution and the formation of precipitation.
Remove the sample:
After the predetermined time is reached, remove the sample and rinse it with distilled water.
Dry the sample and measure its weight and size change.
Corrosion rate calculation:
The corrosion rate is calculated using the weight loss method, and the formula is: Corrosion rate = surface area × time
Weight loss:
Compare the corrosion rates in acidic and alkaline environments.
Result analysis:
Analyze the corrosion resistance of ductile iron pipes under different pH conditions.
Evaluate its applicability in practical applications.
Precautions
Safety protection:
Acid and alkali solutions are corrosive, and the experimenters need to wear protective equipment.
The experiment should be carried out in a well-ventilated environment.
Solution concentration:
Select the appropriate acid and alkali concentration according to the actual application scenario.
Sample processing:
Ensure that the sample surface is clean to avoid impurities affecting the experimental results.
Experimental time:
Set a reasonable immersion time according to the purpose of the experiment to fully evaluate the corrosion performance.
Experimental results and applications
If the ductile iron pipe shows a low corrosion rate in an acid-base environment, it means that it has good corrosion resistance and is suitable for complex chemical environments.
If the corrosion rate is high, additional anti-corrosion measures (such as coating or cathodic protection) may be required.
Through acid-base experiments, the chemical stability of ductile iron pipes can be fully understood, providing a scientific basis for their application in specific environments.
Post time: Feb-28-2025