QFR No - 8000887717
Defect Details
| NC No. | 8000887717 |
| NC Date | 21/08/2024 |
| NC Submission Date | |
| Part No. | S1HT05507B |
| Part Name | OUTER SPRING - K1JF |
| Supplier Name & Code | 100186-SAGAR SPRINGS PRIVATE LIMITED |
| ETL Plant | 1136-ETL Suspension Sanand |
| Defect Details | THICKNESS UNDERSIZE-END COIL THICKNESS UNDERSIZE |
1. Problem Description
| Defect Description | Tip thickness observed 1 mm against specification 2 mm Min . |
| Detection Stage | Inprocess |
| Problem Severity | Function |
| NG Quantity | 156 |
| Is Defect Repeatative? | No |
| Defect Sketch / Photo |
Supplier Communication Details
| Quality Head Email ID | quality@sagarsprings.com |
| Plant Head/CEO Email ID | ajai.singh@sagarsprings.com |
| MD Email ID | sagar@sagarsprings.com |
2. Stock Details & action taken for NG parts
| Location | ETL End | Warehouse | Transit | Supplier FG | Supplier WIP | Total |
|---|---|---|---|---|---|---|
| Total Qty |
4032
|
0
|
0
|
1500
|
0
|
5532
|
| Check Qty |
4032
|
0
|
0
|
1500
|
0
|
5532
|
| NG Qty |
250
|
0
|
0
|
100
|
0
|
350
|
| Scrap | 350 |
| Rework | 0 |
| Under Deviation | 0 |
| Containment Action |
|---|
| SSPL Person visited ETL - Sanad plant and 100% inspection done for tip thickness undersize. |
3. Process Flow
| Process Flow Description |
|---|
| Coiling - Tempering - Spring End Grinding - Shot Peening - Tempering - Scragging - Powder Coating - Final Inspection - Packing - Dispatch |
4. Process Details
| Process / Operation | Spring End Grinding |
| Outsource | No |
| Machine / Cell | Spring End Grinding Machine |
| Machine / Cell No. | Spring End Grinding |
5. Problem Analysis
| Type | Possible Cause | Fact Verification | Jud |
|---|---|---|---|
| Man | Untrained operator | Experienced operator working on this part | O |
| Method | Grinding angle maintained more than spec | Grinding angle maintained maintained more than 300° to maintain spring standing | X |
| Man | Instructions not followed by operator | Operator is experienced, skilled and following instructions | O |
| Machine | Grinding machine condition not OK | CNC Grinding machine ( German make) | O |
| Method | Dressing not done in defined frequncy | Auto dressing system in place | O |
| Material | Free length variation in input springs for Grinding | Free length group wise grinding done | O |
6. Inspection Method Analysis (Current)
| Inspection Method | Gauge |
| Other Inspection Method | |
| Check Point at Final Inspection | Yes |
| Checking Freq. | Sampling |
| Sampling | No |
| Sample Size | sample pla |
7. Root Cause Analysis (Occurance)
| Why 1 | Grinding angle maintained more |
| Why 2 | Grinding angle maintained more than 300° against 250° Min. |
| Why 3 | Grinding angle maintained more for spring standing |
| Why 4 | Spring standing effects function (Noise issue) |
| Why 5 | To maintain spring standing grinding angle maintained more than 300° caused tip thickness less |
| Root Cause (Occurance) | To maintain spring standing grinding angle maintained more than 300° caused tip thickness less |
Root Cause Analysis (Outflow)
| Why 1 | Tip thickness less than 2.0 mm passed |
| Why 2 | Tip thickness not checked |
| Why 3 | Spring standing property is functional effecting parameter so, same is checked and passed |
| Why 4 | |
| Why 5 | |
| Root Cause (Outflow) | Spring standing property is functional effecting parameter so, same is checked and passed |
8. Countermeasure ( Occurrence , Outflow & System side Actions )
| Type | Countermeasure Details | Responsibility | Target Date | Actual Date | Status |
|---|---|---|---|---|---|
| Occurance | Grinding angle will be maintained between 250°-300° to maintain standing property, tip thickness and optimize parameters | SSPL | 05/09/2024 | 05/09/2024 | Completed |
| Outflow | Grinding angle 250° marked on gauge for detection control during grinding | SSPL | 05/09/2024 | 05/09/2024 | Completed |
9. Inspection Method After Customer Complaint
| Change In Inspection System | Yes |
| Change Details | Grinding angle 250° marked on gauge |
| Inspection Method | Gauge |
| Other Inspection Method | |
| Check Point at Final Inspection | Yes |
| Checking Freq. | Sampling |
| Sampling | No |
| Sample Size | sample pla |
10. Evidance of Countermeasure
| Occurance (Before) |
Grinding angle maintained more than 300° 1028_Occurance_Before.pptx |
| Occurance (After) |
Grinding angle will be maintained between 250°-300° to maintain standing property, tip thickness and optimize parameters 1028_Occurance_After.pptx |
| Outflow (Before) |
Grinding angle gauge marked from 270°-330° 1028_Outflow_Before.pptx |
| Outflow (After) |
Grinding angle 250° marked on gauge for detection control during grinding 1028_Outflow_After.pptx |
11. Horizontal Deployment
| Horizontal Deployment Required | Yes |
| Applicable Machine / Model / Plant | Applicable for all Outer Coil Springs |
12. Document Review
| Documents | PFMEA |
| Specify Other Document | OPL |
13. Effectiveness Of Action
| Reviewed Quantity | 5 |
| Reason for submission | END COIL THICKNESS UNDERSIZE |