How Low Temperatures Impact Dye Penetrant Testing

  •  

In this article, we look at how lower inspection temperatures affect the performance of dye penetrant testing cleaners, penetrant and developers 

November 28, 2017  |  by Cheri Stockhausen, Product Applications Manager

Dye Penetrant Testing on Pipe

 

The operating temperature range for penetrant inspection as specified in ASTM E1417 Standard Practice for Liquid Penetrant Testing is 40°F to 125°F (4°C to 52°C), but how is the penetrant inspection affected at temperatures below 40°F (4°C) and can the inspection process be adjusted to achieve acceptable results?

To answer these questions, we evaluated SKC-S cleaner/remover, SKL-SP2 solvent removable dye penetrant and SKD-S2 non-aqueous developer at a range of temperatures in order to figure out what NDT inspectors can expect when using these, or similar quality dye penetrant products when inspecting at lower temperatures

 

Cleaning at lower temperatures

At lower temperatures in the range of 32°F – 50°F (0°C – 10°C), the solvent cleaner will take longer to dry.

We used 75°F (24°C) as our ambient, standard operating temperature, and observed how decreasing temperatures impacted how quickly the solvent cleaner dried. Below are our suggested drying time for solvent-based cleaner/removers at lower temperatures.
 

Temperature Cleaner Drying Time
75°F / 24°C Standard
50°F / 10°C 2 x Standard
40°F / 4°C 3 x Standard
32°F / 0°C 4 x Standard

 

It is critical to make sure the solvent has evaporated during the precleaning step either by wiping with a clean, lint free cloth or using air dryers to ensure a clean and dry part prior to penetrant application. Unevaporated cleaner remaining in indications can impede penetrant entry into the surface breaking indications.

 

Dwelling at lower temperatures

Penetration time should also be extended since the viscosity of penetrant increases with decreasing temperatures, which slows down penetration and can significantly impact the test results.
 

Temperature Dwell Time
75°F / 24°C Standard
45°F / 7°C 2 x Standard
32°F / 0°C 2.5 x Standard

 

Developer at lower temperatures

Developer drying time is more of a challenge and our tests showed the developing action is impeded because of the slower solvent evaporation. When the developer dries, the indications become fuzzy or show excessive bleed out.

Penetrant Developer

We were not able to get good results at 32°F (0°C) because the developer remained wet and did not dry within a reasonable amount of time. At 38 – 40°F (3 – 4°C), and with some air movement, developer film will dry at 5 times the standard time at 75°F (24°C).
 

Temperature Developer Drying Time
75°F / 24°C Standard
40°F / 4°C 5 x Standard

 

A positive note is at low temperatures, we found good indications with extremely small and tight defects. The slow drying rate of the developer film allows greater bleed out of the penetrant from the defect. For large defects, longer development time caused excessive bleed out making indication interpretation more difficult.

 


Contact us if you need more help assessing your low temperature dye penetrant application, or have any questions on additional products for dye or liquid penetrant testing

 

Do you have any tips for low temperature dye penetrant testing or other non-destructive testing?
Share your ideas in the comments section below.

Want to stay up on the latest NDT insights and articles from Magnaflux? 

Subscribe to Magnaflux updates above to get fresh news delivered to your inbox once a week.

Please wait while we gather your results.

Related Blog Entries

PeneCert Test Services

Understanding PeneCert Test Services [SlideShare]

Learn more about test services for in-use penetrant, emulsifiers and developers to comply with ASMT E1417 and AMS 2644.

Read More...

Dye Penetrant Testing on Pipe

How Low Temperatures Impact Dye Penetrant Testing

Learn how lower inspection temperatures effect the performance of dye penetrant testing cleaners, penetrant and developers

Read More...

Liquid Penetrant in Dip Tank

How to Maintain Penetrant Testing System Performance

Learn how liquid penetrant testing products lose performance over time and what to do to ensure penetrant test reliability.

Read More...

Magnaflux Penetrant Inspection

Understanding Type-, Batch- and In-Use-Testing for Liquid Penetrants [Case Study]

Learn the differences between type testing, batch testing and in-use testing for NDT liquid penetrants.

Read More...

Magnaflux Penetrant Inspection

Higher Sensitivity Penetrant Improves Inspection Quality [Case Study]

In this case study, we help an aerospace customer improve inspection quality and consistency with two Magnaflux penetrants

Read More...

Magnetic Particle Crack Comparison

How Brightness and Contrast Impact NDT Inspections

How perception and vision can have a significant impact on probability of detection in non-destructive testing inspections.

Read More...

Dye Penetrant Infographic

The Ultimate Guide to Visible Dye Penetrant Testing [Infographic]

Some handy tips for beginners who are new to visible dye penetrant testing or NDT pros who want an easy reference guide.

Read More...

Magnaflux Penetrant Testing

Exposing 10 Common Misunderstandings about Penetrant Testing

We reveal common misperceptions about liquid penetrant inspection we’ve seen in the field in recent years

Read More...

Magnaflux Water Washable Penetrant

Water Washable versus Post Emulsifiable Penetrant – Which is Right for You?

Learn the differences between water-removable and non-water-washable liquid penetrant to figure out which is right for you

Read More...

AMS 2644 Penetrant Sensitivity Levels

A Guide to AMS 2644 Penetrant Sensitivity Levels

Understand fluorescent liquid penetrant sensitivity levels and how to find the right one for your application

Read More...

Penetrant Testing Demo

How to Do Fluorescent Liquid Penetrant Testing [Video]

Watch a demonstration of the penetrant inspection method according to ASTM E1417, including basic steps for NDT with an AMS 2644 Type 1 penetrant.

Read More...

Leak-Detection-Penetrant-Testing

Leak Detection with Penetrant Testing Process

Read more about using penetrant testing products to inspect for leaks by using fluorescent or visible/colored penetrant to enhance visual detection of leaks.

Read More...

The following required items were not provided or are in the wrong format. Please provide the required responses and submit again:

Name:
  Please enter your name
  Please enter a valid email
Comment Title
Comment: 250 characters left
  Please enter a comment

Title:
Thanks for your teaching update
By:
Skofmox Ventures Ltd Nigeria
Comment:

Thanks.

Magnaflux

155 Harlem Avenue
Glenview, IL 60025, USA
Telephone: +1 847-657-5300
Fax: +1 847-657-5388
Contact Magnaflux Customer Service

Select Your Country North America Mexico Brazil China Europe Russia India New Zealand, Australia, Japan, Southeast Asia
© 2016 Magnaflux - all rights reserved.
top