How to Troubleshoot & Resolve NDT Cleaning Problems

  •  

5 basic steps to identify and solve a NDT aqueous cleaning issue, and a troubleshooting guide with common problems and solutions

By David Geis, Product Manager

 

 

Cleaning parts using aqueous solutions are usually only one part of a much larger manufacturing process. When a problem arises in the process, technicians and engineers need to trace the source of the problem and determine the best solution.

Sometimes a problem will appear immediately after the step causing it. In those cases, troubleshooting can be simple and straightforward.

Other times, problems will only appear after several more processing steps. In these cases, tracing back the root causes can be difficult.

In this article, we outline 5 basic steps you can take to identify and resolve an issue with your aqueous cleaning system, and give you a list of common problems associated with water-based cleaners along with solutions for each.

 

5 Steps to Resolve an Aqueous NDT Cleaner Problem

  1. Identify: Identify the stage in the process where the problem first becomes apparent. Closely observe that stage to find out what makes the problem visible.
     
  2. Find the source: Starting with the identified stage where the problem becomes apparent, work backwards through the process and closely observe each stage to identify the source of the problem.
     
  3. Monitor: When the stage causing the problem is found, monitor that stage to find out if the problem is transient, if it is periodic or if it is inherent to the process.
  4. Dig deeper:
     
    1. If the problem is transient or temporary, identify whether any materials or conditions have changed. Sometimes a simple change in material can introduce unforeseen problems.
       
    2. If the problem is periodic or sporadic, observe the environment and nearby process stages. Sometimes seemingly unrelated operations can influence each other to create a problem.
       
    3. If the problem appears to be inherent in the process stage, collect as much information as possible. Evaluate whether the problem can be eliminated by changing the stage where the problem originates, or by changing the stage where the problem becomes apparent. Determine whether subsequent process stages would be affected.
  5. Take action: Based on the information you have, implement the best solution to the problem.

 

Common Problems with Aqueous Cleaning

If you have concerns or troubles with your process that are not covered in this list, please let us know so our experts can help you find the right solution to your cleaning issues.
 

Part is not clean (general)

Possible Causes Solutions
Cleaner concentration is too low Check cleaner concentration and adjust if necessary
Temperature is too low Check temperature controller and adjust if necessary
Parts are not cleaned for long enough Increase the time that the part is processed
Cleaning solution is loaded with too much soil Check soil levels. If necessary, dump cleaning solution and clean out reservoir to remove soil sediment. Refill with fresh cleaning solution
Parts are not rinsed enough Increase rinsing time. Increase flow of rinse water. Check rinse water for contamination.
Cleaner solution is not aggressive enough Switch to a higher pH, higher alkalinity cleaner, let us help you select the right Daraclean cleaner

 

Part is not clean (hand scrubbing)

Possible Causes Solutions
Parts are not scrubbed enough Increase scrubbing action on part

 

Part is not clean (soak tank, agitated tank, ultrasonic tank)

Possible Causes Solutions
Dirt is not being lifted off surface because ultrasonic power is too low Adjust ultrasonic power setting
Large particles not removed because ultrasonic frequency is too high Adjust ultrasonic frequency setting
Small particles not removed because ultrasonic frequency is too low Adjust ultrasonic frequency setting
Too many parts loaded in bath at one time Decrease number of parts processed at one time

 

Part is not clean (spray washing)

Possible Causes Solutions
Too many parts being processed at one time Decrease number of parts processed at one time to allow more space
Parts are arranged so that spray is inconsistent Rearrange parts in basket

 

Part surfaces are dark after cleaning

Possible Causes Solutions
Cleaner concentration is too high Check bath concentration and dilute if necessary
Bath temperature is too high Check bath temperature controller and adjust if necessary
Metal surface is being attacked by aggressive chemistry Switch to lower pH, l ower alkalinity cleaner solution
Switch to a solution with more corrosion inhibitors
Let us help you select the right Daraclean cleaner

 

Parts have a rainbow pattern similar to heat burn

Possible Causes Solutions
Bath temperature is too high Check bath temperature controller and adjust if necessary
Dryer temperature is too high Check dryer temperature controller and adjust if necessary

 

Part surfaces show pitting, but part surface is otherwise clean

Possible Causes Solutions
Metal surface is being attacked by aggressive chemistry     Switch to lower pH, lower alkalinity cleaner solution
Switch to cleaner solution containing more corrosion inhibitors
Add low-concentration corrosion inhibitor to rinse water
Use a protective coat of machine oil for long-term parts storage
Let us help you select the right Daraclean cleaner

 

Part surfaces have starburst pattern

Possible Causes Solutions
Part surface being damaged by ultrasonics Decrease ultrasonic power
Increase ultrasonic frequency

 

Cleaning solution turns yellow or brown

Possible Causes Solutions
Bath temperature too high Check bath temperature controller and adjust as necessary
Cleaner concentration too high Check cleaner concentration
Cleaning solution oxidized over time Ambient air can cause certain cleaner formulations to oxidize and darken over time. This does not affect the usefulness or cleaning ability of the solution.
Cleaning solution loaded with too much emulsified oil Check soil levels. If necessary, dump cleaning solution and clean out reservoir to remove soil sediment. Refill with fresh cleaning solution.

 

A film of oil develops on top of the cleaning solution

Possible Causes Solutions
Cleaner concentration too low Check cleaner concentration and adjust as necessary
Bath temperature too low Check bath temperature controller and adjust as necessary
Oil-phase de-foaming agent added  If an oil-based de-foaming agent is in use, the film of oil on top of the solution is there to prevent the formation of foam
Oil loading in cleaner tank too high  Check soil levels. If necessary, dump cleaning solution and clean out reservoir to remove soil sediment. Refill with fresh cleaning solution
Cleaner chemistry not compatible with soils being cleaned Switch to a different cleaner that is chemically compatible with the base material and soils being cleaned, let us help you select the right Daraclean cleaner

 

Excessive foam

Possible Causes Solutions
Too much agitation Decrease agitation until foaming stops
Spray pressure and volume too high Check pressure and flow regulators and adjust if necessary
Recirculation pump cavitating Check condition of pump and check for flow blockage
Cleaner concentration too high Check cleaner concentration and adjust as necessary
Bath temperature too low Check bath temperature controller and adjust as necessary
Cleaner de-foaming agents used up Replenish de-foaming agents
Foaming soil or additive introduced to bath If soil is naturally foaming, a different cleaner formulation may be required, or additional de-foaming agents may need to be used, let us help you select the right Daraclean cleaner

 

Parts have a film of oil when removed from the cleaning solution

Possible Causes Solutions
Parts not completely cleaned See above recommendations for Part is not clean
Oil loading of cleaner bath too high Check soil levels. If necessary, dump cleaning solution and clean out reservoir to remove soil sediment. Refill with fresh cleaning solution
Oil contamination of rinse water Check rinse water to make sure only clean water is used for parts rinsing
Parts have excessive grease or heavy oils before cleaning Add pre-cleaning step to remove excessive grease and heavy oil from parts
Cleaner chemistry not compatible with soils being cleaned Switch to a different cleaner that is chemically compatible with the base material and soils being cleaned, let us help you select the right Daraclean cleaner

 

Parts have a white film or powdery residue

Possible Causes Solutions
Parts not sufficiently rinsed after cleaning Check rinse water to make sure only clean water is used for rinsing
Increase rinsing time or add second rinse stage
Increase rinse water flow or agitation in rinse tank.
Hard water scale forming on parts Install water conditioners on the processing line
Switch to a different cleaner that has better hard water tolerance, let us help you select the right Daraclean cleaner
Silicates precipitating on parts Switch to a different cleaner that does not use silicates, let us help you select the right Daraclean cleaner

 

Excessive scale buildup on tank fixtures or heater

Possible Causes Solutions
Hard water scale Install water conditioners on the processing line
Switch to a different cleaner that has better hard water tolerance, let us help you select the right Daraclean cleaner
Silicates precipitating on parts Increase maintenance routines to clean scale off more frequently
Switch to a different cleaner that does not use silicates, let us help you select the right Daraclean cleaner

 

Part surfaces appear grainy after cleaning

Possible Causes Solutions
Part is being etched by galvanic action between dissimilar metals Verify that all equipment and cleaning tanks are properly grounded. Verify that part baskets or fixturing are properly grounded
Part is being attacked by aggressive cleaner chemistry  Switch to a cleaner that is compatible with the base metal of the parts, let us help you select the right Daraclean cleaner

 

Color of alloy changes after cleaning

Possible Causes Solutions
Part is being anodized by galvanic action between dissimilar metals Verify that all equipment and cleaning tanks are properly grounded. Verify that part baskets or fixturing are properly grounded
Part is being attacked by aggressive cleaner chemistry Switch to a cleaner that is compatible with the base metal of the parts, let us help you select the right Daraclean cleaner

 

Cleaner tank begins to rust at comers

Possible Causes Solutions
Galvanic action is corroding metal of cleaner tank Verify that all equipment and cleaning tanks are properly grounded
Let us help you determine the root cause and solution to advanced cleaning problems

 

Cleaner system begins to leak

Possible Causes Solutions
Galvanic action is corroding metal of cleaner tank Verify that all equipment and cleaning tanks are properly grounded
Rubber gaskets and seals being attacked by oils removed from parts Verify all seals used in cleaning equipment are compatible with the oils and solvents being removed from parts at the temperatures being used
Let us help you determine the root cause and solution to advanced cleaning problems

 

 

We are ready to provide additional assistance with troubleshooting of cleaning processes, help with selecting the best cleaning solution for a part or soil, or to answer general questions about industrial parts cleaning.

Want to stay up on the latest NDT insights and articles from Magnaflux? Subscribe to Magnaflux updates get fresh news delivered to your inbox.

Please wait while we gather your results.

Related Blog Posts

6 Factors to Get the Best Aqueous Cleaning Results

In this article, we will go over the six key factors to a successful cleaning process and give you some Pros & Cons to consider for each

Read More...

Understanding the Magnaflux Shelf Life Statement for NDT Chemicals

Understanding the Magnaflux Shelf Life Statement for NDT Chemicals

Answering popular questions regarding shelf life for magnetic particle and liquid penetrant products used in nondestructive testing

Read More...

Understanding Safety Data Sheets

Understanding Safety Data Sheets: Do You Know What’s in the Chemicals You Handle?

We highlight the 5 major sections to understand on a Safety Data Sheets (SDS) in accordance with US OHSHA Hazcom 2012 GHS regulations

Read More...

5-Point Guide to Understanding Aqueous NDT Cleaning

A real-life approach to understanding industrial aqueous cleaning before and after nondestructive testing

Read More...

What You Need to Start-up In-house Testing [Checklist]

What You Need to Start-up In-house Testing [Checklist]

Step-by-step process listing everything from the equipment needed in magnetic particle testing and liquid penetrant testing to preparation for NDT audits

Read More...

How to Troubleshoot & Resolve NDT Cleaning Problems

5 steps to identify and solve a NDT aqueous cleaning issue, and a troubleshooting guide with common problems + solutions

Read More...

Success with the Right Precleaning

Prepare for Penetrant Testing Success with the Right Precleaning

Learn why proper precleaning before liquid penetrant inspections can make or break your nondestructive testing results

Read More...

JOIN OUR MAILING LIST TO RECEIVE THE LATEST NDT INSIGHTS AND ARTICLES FROM MAGNAFLUX

Magnaflux

155 Harlem Avenue
Glenview, IL 60025, USA
Telephone: +1 847-657-5300
Contact Magnaflux Customer Service

Select Your Country North America Mexico Brazil China Europe India New Zealand, Australia, Japan, Southeast Asia
© 2024 Magnaflux - All Rights Reserved.
top