Liquid penetrant inspection (LPI), or dye penetrant inspection, is a reliable, efficient, and cost-effective method for detecting surface flaws of welds, castings, and other components that cannot be destroyed. LPI or dye penetrant is a portable surface inspection method, allowing our Engaged Experts to conduct comprehensive onsite evaluation.

What is Liquid Penetrant Inspection Utilized For?

Liquid penetrant inspection is a valuable tool for evaluating non-ferromagnetic and non-metallic materials. In addition to utilizing dye in checking for defects and cracks, it can also be used to determine other surface characteristics, such as porosity. 


The Dye Penetrant Inspection process

Parts must go through a pre-cleaning process (etch, alkaline or solvent-cleaning) before the liquid penetrant is applied. After allowing proper dwell time, excess penetrant is removed from the surface (but not from any possible defects), and the part is dried. Then a developing powder is applied; this developer pulls up the dye that has seeped into cracks or pores, resulting in visible marks or indications that identify surface flaws. Based on the results, an inspector then provides a report with the type, number and size of defects on a component.


Element’s Liquid Penetrant Inspection (LPI) qualifications 

Our non-destructive testing (NDT) experts are well-trained in liquid penetrant inspection and hold Level II and III certifications from ASNT, among other qualifications. Element provides Type II non-fluorescent NDT services to all of the various commercial and nuclear codes, as well as Type I fluorescent inspection to aerospace, government, nuclear, and after-market applications.

For more information about our liquid penetrant inspection services or to request a quote, contact us today. 

  • A 55’ x 15’ wet room equipped with a 2.5-ton hoist for processing large specimens
  • All methods of dye penetrant inspection, including lipophilic and hydrophilic emulsified systems, as well as water washable and solvent removable to meet any sensitivity requirements
  • Certification by major prime contractors for the inspection of fracture critical hardware
  • In-house chemical etching services, which allows for "one-stop lab" processing
  • Our testing facility at Element Altbach, Germany offers high-volume Liquid Penetrant Inspection with a capacity of up to 12,000 parts per day
American Metals Society
AMS 2645, AMS 2646, AMS 2647
American National Standards Institute
American Petroleum Institute
API 1104
American Society of Mechanical Engineers
ASME Section III, ASME Section V, ASME Section VIII
American Society for Metals
ASM 2700
American Society of Non-Destructive Testing
American Society for Testing and Materials
ASTM E165, ASTM E1417, ASTM E1418
American Welding Society
AWS D1.1
Deutsches Institut Fur Normung E.V.
DIN EN 571-1, DIN EN ISO 3452-5, DIN EN ISO 3452-6, DIN EN 10228-2, DIN EN ISO 3452-2, DIN EN 1371-1, DIN EN 1371-2
EN 571
Military Standard
MIL STD 271F, MIL STD 6866, NAVSEA T9074-AS-GIB-010/271, MIL-STD-2132, MIL-I-6866, MIL-STD-1907
National Aerospace Standard
Society of Automotive Engineers
SAE J426
Various Customer Specifications
Including Aerojet Rocketdyne, Boeing, Bombardier, Cessna, GE, Hamilton Sunstrand, Honeywell, Northrop Grumman, and Rolls Royce.
High-volume Liquid Penetrant Inspection (LPI) Center at Element Altbach, Germany

Our team of over 9,000 Engaged Experts in North America, Europe, The Middle East, Australia, Asia and Africa are ready to help you.