We employ a rigorous quality control process, overseeing each step of product manufacturing, monitoring process requirements at every stage to ensure product quality meets the necessary standards. We also ensure consistency and traceability, promptly addressing and rectifying any defects or issues according to established protocols.
The table below provides an example of management control plan within the conventional process of vacuum powder metallurgy for sintered neodymium iron boron (NdFeB) magnets, along with quality control methods and reactionnse plans.
|
No. |
Process |
Process Description |
MFG Devices |
Process Characteristics |
Process Specification |
Measurement Technique |
Sample Volume |
Sample Frequency |
Control |
Reaction |
|
1 |
Raw Material Incoming Inspection |
\ |
ICP |
Appearance/ Component |
Raw Material Inspection Standard |
ICP |
One Sample |
Per Batch |
Metallic Raw Material Inspection Procedure |
Rework |
|
2 |
Raw Material Pretreatment |
Pure Iron |
Buffing Machine |
Buffing Time |
Process Parameters |
Time Relay |
Once |
Per Batch |
Raw Material Treatment Work Instruction |
Rework |
|
Appearance |
Clean, No Rust |
Visual Measurement |
100% |
Per Batch |
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|
3 |
Smelting Process |
Ingredients |
Electron Platform Scale |
Ingredient Weight |
Process Parameters |
Electron Platform Scale |
Once |
Per Batch |
Raw Material Ingredient Work Instruction |
Rework |
|
Melting |
Vacuum Strip Casting Furnace |
Vacuum Degree |
Process Parameters |
Vacuum Gauge |
Once |
Per Batch |
Alloy Smelting Operation Procedure |
Adjust/ Rework |
||
|
Melting Temperature |
Thermodetector |
Once |
Per Furnace |
|||||||
|
Smelting Power |
Power Meter |
Once |
Per Furnace |
|||||||
|
Casting Slice Thickness |
Micrometer |
Some PCS |
Per Furnace |
Casting Inspection Working Instruction |
Adjust/ Rework |
|||||
|
Casting Slice Alloy Component |
ICP |
Once |
Per Furnace |
|||||||
|
Casting Slice Appearance |
Silvery white, no red, black or yellow |
Visual Measurement |
Once |
Per Furnace |
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|
4 |
Hydrogen Crushing Process |
Hydrogen Crushing |
Hydrogen Crushing Furnace |
Hydrogen Pressure |
Process Parameters |
Pressure Gauge |
Once |
Per Furnace |
Hydrogen Crushing Operation Procedure |
Adjust/ Rework/ Degrade |
|
Hydrogen Temperature |
Thermodetector |
100% |
Continuously |
|||||||
|
Hydrogen Content |
Outsourcing |
Every half a year |
\ |
|||||||
|
Particle Size |
Laser Particle Size Analyzer |
Once |
Per Batch |
|||||||
|
5 |
Milling Process |
Jet Milling |
Jet Milling |
Nitrogen Pressure |
Process Parameters |
Pressure Gauge |
100% |
Continuously |
Jet Milling Operation Procedure |
Adjust/ Rework |
|
Grinding Material Weight |
Weighting Instrument |
100% |
Continuously |
|||||||
|
Blender |
Mixing Amount |
Electronic |
Once |
Per Batch |
Blender Operation Procedure |
|||||
|
Laser Diffraction Particle Size Analyzer |
Particle Size |
Laser Particle Size Analyzer |
Once |
Per Batch |
Laser Particle Size Tester Operation Procedure |
|||||
|
6 |
Pressing Process |
Weighing |
Rare Earth Permanent Magnet Molding Press Machine |
Weight |
Process Parameters |
Weighting Instrument |
Once |
Continuously |
Magnet Molding Operation Procedure |
Adjust/ Rework/ Scrap |
|
Pressing |
Orientation Magnetic Field |
Gauss Meter |
Once |
Every Shift |
||||||
|
Pressing Dimension |
Vernier Caliper |
Some PCS |
Per Hour |
|||||||
|
Pressing Piece Weight |
Electronic Scale |
Some PCS |
Per Hour |
|||||||
|
Oxygen Content |
Oxygen Meter |
100% |
Continuously |
|||||||
|
Isostatic Pressing |
Isostatic Pressing Machine |
Isostatic |
Pressure Gauge |
100% |
Continuously |
Isostatic Pressing Operation Procedure |
||||
|
7 |
Sintering Processing |
Sintering |
Vacuum Sintering Furnace |
Sintering Temperature |
Process Parameters |
Temperature Controller |
100% |
Continuously |
Sintering Operation Procedure |
Adjust/ Rework/ Scrap/ Degrade |
|
Sintering Time |
Temperature Controller |
100% |
Continuously |
|||||||
|
Vacuum Degree |
Vacuum Gauge |
100% |
Continuously |
|||||||
|
8 |
Inspection |
Appearance Inspection |
Visual Inspection |
Appearance |
No Oxidation, Impurity, Fissure |
Visual Measurement |
100% |
Per Furnace |
Blank Property Inspection Standards/Magnet Blanks Performance Inspection Operation Instruction |
Adjust/ |
|
Dimension Inspection |
Vernier Caliper |
Length/Width/Height |
Process Parameters |
Vernier Caliper |
Some PCS |
Per Furnace |
||||
|
Magnetic Performance Inspection |
Permanent Magnet Material Precision Measurement System |
Magnetic Properties |
Br, Hcb, Hcj, Hk, Bhmax |
Permanent Magnet Material Precision Measurement System |
Some PCS |
Operation |
||||
|
9 |
Machining Process |
Cutting |
Cutting Machine |
Length/ Width/Height/ Outer Diameter |
Process Parameters |
Micrometer |
100% |
Per Batch |
Cutting Work Instruction |
Rework/ Reinspect/ Scrap |
|
Grinding |
Grinding Machine |
Micrometer |
100% |
Per Batch |
Grinding Work Instruction |
|||||
|
Trepanning |
Trepanning Machine |
Inner Diameter |
Micrometer |
100% |
Per Batch |
Trepanning Work Instruction |
||||
|
Chamfering |
Chamfering Machine |
Chamfering |
Projector |
GB/T 2828 |
Per Batch |
Chamfering Work Instruction |
||||
|
10 |
Semi-finished Products Inspection |
Appearance Inspection |
\ |
Appearance |
No oil stain, oil, dirt or oxidation layer on surface; Chips etc. |
Visual Measurement |
Full Inspection |
Per Batch |
Semi-finished Products Appearance Inspection Standards |
Rework/ Reinspect/ Scrap |
|
Dimension Inspection |
Micrometer |
Length/Width/Height/Outer Diameter/Inner Diameter |
Process Parameters |
Micrometer |
5%/Batch |
Per Batch |
X-R Control Chart |
|||
|
11 |
Plating Process |
Rinse Washing |
Rinse Tank |
Time |
Process Parameters |
Change |
100% |
Per Batch |
Cleaning Technology |
Adjust/ |
|
Acid Washing |
Descaling Tank |
Time |
Automatic Control |
100% |
Per Batch |
Cleaning Technology |
||||
|
Coating |
Coating Tank |
PH Value |
PH meter |
Once |
Everyday |
Coating Technology |
||||
|
Temperature |
Temperature Controller |
100% |
Per Batch |
Coating Technology |
||||||
|
Time |
Automatic Control |
100% |
Per Batch |
Coating Technology |
||||||
|
12 |
Final Products Inspection |
Appearance Inspection |
\ |
Appearance |
No bumps, particle, water ripple, waterlogging, broken corner, scratch and other defects that beyond the standards on the surface |
Visual Measurement |
100% |
Per Batch |
Magnets Surface Quality Standard after Coating |
Rework/ |
|
Dimension Inspection |
Digital Caliper |
Length/Width/ Height/ Outer Diameter/ Inner Diameter |
Products Requirements |
Digital Caliper |
GB2828 |
Per Batch |
Final Products Inspection Standards |
Rework/ |
||
|
Coating Thickness |
Coating Thickness Detector |
Coating Thickness |
Coating Thickness Detector |
1-2PCS |
Per Batch |
|||||
|
13 |
Packing Process |
Marking |
Auto Marking Machine |
\ |
Products Requirements |
Visual Measurement |
Random 10pcs |
Per Batch |
Marking Work Instruction |
Rework |
|
Packing |
Package Machine |
\ |
Counting |
100% |
Per Batch |
Packaging Work Instruction |
Rework |
|||
|
14 |
Shipment |
\ |
\ |
Carton Size & Quantity |
Products Requirements |
Counting |
100% |
Per Batch |
Shipment Work Instruction |
Rework |
