
Magnaflux 2461 Centrifuge Tube for Visible MPI Bath Monitoring
The Magnaflux 2461 is a 100 ml ASTM pear-shaped centrifuge tube used to monitor the bath concentration and contamination level of magnetic particles in Magnavis 7C and 7HF visible (non-fluorescent) magnetic particle baths. Graduated from 0 to 1.5 ml in 0.10 ml increments, the 2461 provides the precise readings needed to maintain consistent bath strength and reliable inspection results.
Note: Centrifuge tube only — stand must be purchased separately.
Why Bath Concentration Monitoring Matters
The amount of magnetic particles per gallon of fluid in the inspection bath is called its concentration or bath strength. Maintaining the correct concentration is critical:
- Too low: Weak or absent indications — defects may go undetected
- Too high: Heavy background buildup masks indications — fine defects become invisible
- Correct range: Consistent, reliable indications for all defect types
Bath strength should be checked at least once per day, after thorough mixing and agitation of the entire bath. The gravity settling method using an ASTM pear-shaped centrifuge tube is the most widely used and accepted technique.
Settling Time for Visible Baths: After drawing your sample, allow it to settle for 60 minutes before reading concentration — oil-based visible baths (Carrier II) require the full settling period for accurate results. Check your procedure specification for the target concentration range for 7C and 7HF baths — typically 1.2–2.4 ml/100 ml per ASTM E1444. Always agitate the bath for at least 15 minutes before sampling to ensure particles are fully suspended and readings are accurate.
Compatible Magnetic Particles
- Magnaflux 7C — Black non-fluorescent wet method particles for bulk oil-based MPI baths
- Magnaflux 7HF — Black non-fluorescent oil-based aerosol for field and spot inspections
Specifications
| Property | Specification |
|---|---|
| Part Number | 2461 |
| Volume | 100 ml |
| Graduation Range | 0 – 1.5 ml |
| Graduation Increment | 0.10 ml |
| Shape | ASTM pear-shaped |
| Compatible Particles | Magnavis 7C, 7HF (visible/non-fluorescent) |
| Stand Included | No — sold separately |
| Brand | Magnaflux |