Liquid Penetrant Testing (Fluorescent Penetrant Inspection - FPI)

The perfect non-destructive-test (NDT) solution for inspection of components, Liquid Penetrant Testing, or Fluorescent Penetrant Inspection (FPI), is commonly used in the aerospace and medical industries. Precision surface finishing leaders, Kemet, now offer FPI systems with advanced process control that ensures repeatability, process safety and traceability of each batch within the set parameters.

Fluorescent Penetrant Inspection - FPI

About FPI non-destructive testing

Fluorescent penetrant inspection is one form of non-destructive testing. It involves the application of fluorescent dye to the surface of an object in order to detect any possible faults. The FPI method is used in many different industries.

In the aviation industry, parts cleaning and non-destructive testing (NDT) are closely related. The surfaces of objects to be inspected during servicing and repairs are cleaned using chemical or mechanical methods to remove scale, rust and dirt. If necessary, coatings which may affect the inspection are also removed. When manufacturing new parts, objects are e.g. anodized or pickled and non-destructive testing is then used to determine the flawlessness of the parts.

FPI Solutions for Manufacturing and MRO

The systems meet the ASTM E1417 FPI standard common to both the aerospace and medical industries. Kemet offer a range of standard systems as well as the flexibility to combine automated and manual operation to provide streamlined, maintainable NDT inspection, with integrated waste water handling and extraction systems as options, to generate cost savings on process chemicals, labour and energy consumption.

Finnsonic have supplied fully automated systems for airframe components, turbine blades, and medical implants as well as smaller manual systems for less critical parts. An intelligent combination of automation and manual handling can reduce labour requirements, while an adjustable layout can provide a small footprint. As with Finnsonic’s cleaning machines, these FPI systems are durable, safe, ergonomic and user-friendly.

A variety of systems are available, from flexible manual roll track spray lines with a small footprint, to fully automated roll conveyor immersion lines for high capacity, mass production with dipping penetrant application, “Dust Storm” developer chamber and integrated pre and post wash. Further options include material handling and batch traceability via a data log, fully automated penetrant and developer spray, basket rotation, basket trolleys and automatic loading/unloading conveyors

Automated FPI Line

  • The automatic FPI line ensures process safety and high capacity with minimal operator involvement.
  • User friendly operator interface with data collection of each batch for quality control and traceability.
  • Buffering infeed conveyor, various conveyor sizes available on request.
  • Pre-cleaning with ultrasonic technology provides precision cleaning with automatic tuning feature.
  • Automatic electrostatic penetrant spray with rotation of the carrier, PLC controlled contact time.
  • Water wash with dedicated spray nozzles, penetrant residues removed from the waste water in a separate storage tank.
  • Emulsifier, PLC controlled time critical treatment.
  • Automatic electrostatic developer spray with rotation of the carrier, PLC controlled contact time.
  • The carriers can hold parts with various sizes and shapes.

Liquid Penetrant Testing machine

Fluorescent Penetrant Inspection machine

FPI solution concepts

Manual roll track spray line

  • Ideal for inspection of wheel and brake parts
  • Flexible with a small footprint
  • Optional dip or electrostatic spray methods

Roll conveyor immersion line

  • Automated high capacity system for mass production
  • Penetrant application by dipping
  • “Dust Storm” type developer chamber

Manual chain hoist line

  • Higher throughput with minimum foot print
  • Double FPI line for turbofan MRO

Automated line

  • Integrated process with pre and post wash
  • Automated process control and material handling
  • Batch traceability via data log

Booth line

  • A manual monorail system
  • Inspection of large parts such as aero-structures

Key features and benefits

  • Intelligent combination of automation and manual handling provides labour cost savings
  • Traceable and reliable inspection
  • Adjustable layout provides small footprint
  • Low consumption of process chemicals
  • Low operational costs
  • Durable and safe
  • Ergonomic/User-friendly

Optional features include

  • Fully automated penetrant and developer spray
  • Basket rotation
  • Upgraded ventilation systems
  • Integrated Pre-cleaning and cleaning after FPI processes
  • Basket trolleys and automatic loading/unloading conveyors

Main applications

  • Engine parts
  • Aerostructures
  • Wheel hubs
  • Brake parts
  • Landing gear
  • Automotive parts