Penetrant Line | DPI & FPI Industrial Process Systems

NEXSEN penetrant immersion tanks are designed and manufactured using a custom engineering approach based on specific customer requirements and application needs. During the design phase, parameters such as part geometry, dimensions, production volume, penetrant inspection method (visible or fluorescent), and process workflow are carefully evaluated to determine the most suitable penetrant processing system.

NEXSEN penetrant immersion tanks are used as part of the penetrant testing process to perform penetrant application, emulsification, rinsing, developing, and drying operations in a controlled and repeatable manner. These tanks ensure consistent penetrant coverage and reliable inspection results by providing stable process conditions throughout the inspection cycle.

The systems can be configured as individual tanks or as part of a complete penetrant inspection line, depending on production requirements. NEXSEN penetrant immersion systems can be designed for manual, semi-automatic, or fully automatic operation.

A typical penetrant immersion system may include the following process stations:

Penetrant application tank
Emulsifier tank (lipophilic or hydrophilic)
Water rinse tank
Drying oven
Developer application system (dry powder or wet developer)
Final drying station

Tank Design Features

NEXSEN penetrant immersion tanks are manufactured using industrial-grade materials resistant to penetrant chemicals and cleaning agents, ensuring durability and long-term operation in demanding industrial environments.

Standard design features may include:

Chemical-resistant stainless steel tank construction
Overflow and filtration systems
Temperature control systems
Chemical level monitoring systems
Agitation systems for penetrant uniformity
Drainage and maintenance access points
Adjustable part baskets or fixtures
Integrated lifting systems or hoists for heavy components

Process Control Parameters

To ensure consistent penetrant inspection results, the following technical parameters are considered during system design:

Penetrant dwell time
Penetrant sensitivity level (Level 1 / Level 2 / Level 3)
Emulsification time and concentration
Rinse water pressure and flow rate
Drying temperature control
Developer application uniformity
Chemical contamination monitoring

Typical Penetrant Process Flow

A typical penetrant inspection process may include the following stages:

Pre-cleaning
Penetrant immersion (Level 1 / Level 2 / Level 3 penetrant)
Penetrant dwell time
Excess penetrant removal
Emulsifier application (lipophilic or hydrophilic)
Water rinse
Drying
Developer application (dry powder or wet developer)
Final drying (if required)
Inspection under UV-A or white light

Applicable Standards

NEXSEN penetrant immersion tank systems can be designed in accordance with the following international standards:

ISO 3452 – Non-destructive testing — Penetrant testing
ASTM E165 / E165M – Liquid Penetrant Examination
ASTM E1417 / E1417M – Liquid Penetrant Testing
ASME Boiler and Pressure Vessel Code Section V – Article 6
AMS 2644 – Penetrant inspection materials
ISO 3059 – Lighting requirements for NDT

Applications

NEXSEN penetrant immersion tank systems are used to detect surface-breaking defects such as cracks, porosity, seams, laps, and other surface discontinuities in industries including:

Aerospace and defense
Automotive manufacturing
Casting and forging industries
Railway systems
Oil and gas equipment manufacturing
General industrial manufacturing

Click the link below for our article on What is the Penetrant Testing:

What is the Penetrant Testing?

Click the link below for our article on Penetrant Sensitivity Levels:
Penetrant Sensitivity Levels

Click the link below for our Penetrant Bench products:
Penetrant Bench

Click the link below for our Penetrant Cabinet products:
Penetrant Cabinet

For videoscope inspection of materials such as shafts and couplings after penetrant testing, the following product may be of interest to you:
Shaft and Coupling Inspection System

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