Preventive maintenance for Tanks and impellers

 

Maintenance is the process that ensures that machinery and equipment are in a condition to be used according to the owner's or user's desires. There are different types of maintenance:

 

1. Breakdown Maintenance:

   Breakdown maintenance is the oldest concept of maintenance. It involves repairing the parts that are damaged without any planned schedule. This type of maintenance has its drawbacks, including:

   - Lack of warning signals when machinery and equipment start to deteriorate.

   - Impact on production due to the long lead time for ordering some parts.

   - Inability to plan production schedules, leading to inefficient manufacturing processes.

 

2. Preventive Maintenance:

   Preventive maintenance is a planned maintenance approach. It involves the regular inspection, cleaning, repair, or replacement of equipment according to a predetermined schedule. Preventive maintenance is crucial for industrial facilities as it not only extends the lifespan of machinery but also ensures efficient production processes. Benefits include:

   - Prolonged equipment lifespan.

   - Reduction in disruptions during the production process.

   - Maintenance of the highest level of production process efficiency.

 

Source: https://www.thaiparker.co.th/th/articles/processing-service/What-is-Preventing-Maintenance

 

 

Objectives of Tank and Agitator Maintenance

 

1. Ensuring Effectiveness:

   - The primary goal is to enable agitators to operate efficiently, ensuring that tanks and agitators can be utilized to their full capabilities.

 2. Enhancing Performance and Longevity:

   - Maintenance aims to boost the performance of tanks and agitators, contributing to their longevity. Regular maintenance prevents wear and tear, addressing abnormalities or malfunctions that may occur over time without repairs. This helps in avoiding leaks in tanks and malfunctions in agitators.

 3. Ensuring Safety:

   - Safety is a crucial objective. Machinery and tools must be sufficiently safe for users. If equipment is faulty and unable to function normally, it may lead to accidents and injuries. Proper maintenance helps control potential hazards.

 4. Environmental Impact:

   - Maintenance contributes to reducing environmental impact. Malfunctioning and poorly maintained equipment can release dust, chemical fumes, or loud noises, posing dangers to operators and those nearby. Effective maintenance helps mitigate these environmental issues.

 5. Energy and Lubricant Efficiency:

   - Well-maintained tanks and agitators operate smoothly without oil leaks, resulting in minimal energy consumption. This efficiency contributes to cost savings in terms of electricity and lubricant usage.

 

 

Tank Maintenance

  Even though tanks are a vital part of the production process that may not demand constant attention or frequent checks compared to other systems, it is crucial to conduct regular inspections to ensure their effective operation. This is particularly true for routinely used equipment like mixing tanks.

 

  1. General Inspection:

• Verify the overall condition of the tank to ensure it maintains its original shape without any deformities or swelling.

• Confirm that the tank legs or the entire structure are positioned straight and parallel to the ground, without any tilting.

• Inspect the tank's surface for smoothness, ensuring there are no cracks or signs of corrosion.

  2. Color Assessment:

• Examine whether the color of the tank has undergone significant changes or if there are faded or discolored spots. Excessive color alterations may indicate wear and tear.

  3. Surface Examination:

• Check the tank for any stains or marks, especially on stainless steel tanks, ensuring there are no rust stains that could lead to potential leaks.

  4. Planning In-Depth Inspections:

• Schedule periodic in-depth inspections conducted by experts to prevent severe damage. This may include weld inspections using penetrant tests and checking the thickness of the tank walls.

 

 

Non-Destructive Evaluation of Stainless-Steel Tank Welds Using PT Test

  Non-destructive testing (NDT) is a critical process in ensuring the integrity of stainless-steel tank welds. The Liquid Penetrant Inspection (PT Test) is a non-destructive method employed for evaluating the soundness of these welds. This technique involves the application of a penetrant liquid, utilizing its unique ability to infiltrate narrow or confined areas within the weld, such as pitting or other discontinuities. The underlying principle of this method is "Capillary action" or the liquid's capability to penetrate.

 

  Principles of PT Test:

    The PT test relies on several key factors that determine the efficacy of the evaluation:

       1. Size of Discontinuity:

           - The PT test is more effective in detecting larger non-continuous areas or defects within the weld. The size of the discontinuity influences the extent to which the liquid penetrates.

       2. Liquid Surface Tension:

           - Adequate surface tension in the liquid used for the PT test is essential. This property ensures effective penetration and coverage across the weld's surface.

       3. Wet Ability:

           - The wet ability of the liquid refers to its capacity to spread across the surface of the material being tested. The liquid's ability to wet the surface affects its spread and the likelihood of detecting defects.

 

Source: https://naichangmashare.com/2020/02/15/penetrant-testing-basic/

 

Care Tips for Stainless Steel Tanks:

  1. Regular Cleaning:

• Clean the tank thoroughly after each use to prevent the accumulation of residues or contaminants.

  2. Acid Cleaning Precautions:

• If using acids for cleaning stainless steel, ensure proper rinsing with water and verify that no residual acid remains in the tank.

  3. Product Change Considerations:

• When switching cleaning products, start with the mildest one first and conduct a small test cleaning in a limited area to ensure the substance does not damage the surface.

  4. Avoiding Rust Stains:

• Prevent the use of cleaning equipment made of steel to avoid the occurrence of rust stains. opt for non-ferrous cleaning tools to safeguard against corrosion.

 

Things to Avoid with Stainless Steel Tanks:

  1. Avoid Coating with Beeswax or Greasy Substances:

• Refrain from coating stainless steel with beeswax or greasy substances, as these can make dust or stains adhere more easily, making cleaning more challenging.

  2. Avoid Cleaning Products with Chloride and Halide Compounds:

• Avoid using cleaning products containing chloride and halide compounds such as bromine, iodine, and fluoride, as they may lead to corrosion and damage the stainless-steel surface.

  3. Avoid Hydrochloric Acid for Cleaning:

• Do not use hydrochloric acid for cleaning, as it may cause needle-like pitting and stress corrosion cracking on the surface.

 

Source: bestkitchen9.com/th/articles/172896-การดูแลรักษา%20และทำความสะอาดอุปกรณ์สแตนเลส;January 6, 2024

 

 

Maintenance of Impellers: Ensuring Safety and Efficiency:

  1. Intact Impeller Cover:

• Ensure that the impeller cover is in good condition to prevent accidental contact with rotating parts, minimizing the risk of accidents.

  2. Secure Motor Fastenings:

• Regularly check and ensure the stability and strength of motor fastenings to prevent any unexpected loosening during operation.

  3. Safety During Maintenance:

• When performing maintenance and repairs, always cut off the power supply to guarantee the safety of personnel.

  4. Condition of Electrical Wires:

• Verify that electrical wires are in optimal condition to avoid electrical hazards.

 

Maintenance Procedures:

  1. Lubricate Moving Parts:

• Ensure that lubrication points are adequately filled with lubricating oil suitable for the motor gear set, impeller set, and replace as needed every six months.

  2. Seal Replacement:

• Change the impeller seal based on wear conditions suitable for the operational timeframe.

  3. Cooling System Check:

• Examine the cooling system pipe for the mechanical seal, ensuring it is intact without cracks or fluid leakage.

  4. Regular Maintenance every 6 months:

• Perform routine maintenance every six months, addressing fragile components and conducting repairs. Check the alignment to maintain the proper alignment of each impeller.

  5. Inspect Bearing Lubrication Monthly:

• Regularly inspect the lubrication of impeller bearings every month.

  6. Belt Tension Check:

• Verify the tension of belts, ensuring they adhere to the specified standards.

  7. Plan Annual In-Depth Inspection:

• Schedule an annual in-depth inspection conducted by specialized personnel to prevent significant damage.

 

Benefits of Maintenance:

• Cost Reduction:

• Reduced maintenance costs by addressing issues before they escalate.

• Decreased Machinery Downtime:

• Reduced chances of machinery and equipment breakdowns, minimizing production downtime.

• Efficient Production:

• Enhanced production efficiency through well-maintained machinery.

• Optimized Spare Parts Inventory:

• Reduced inventory of spare parts required for maintenance.

• Increased Production Efficiency:

• Improved overall production efficiency with effective maintenance planning.

• Minimized Production Halts:

• Decreased occurrences of production halts due to efficient maintenance practices.