Improvements Presentation for upload.pptx

Improvements

1. IMPROVEMENTS IN PRODUCTS/ PROCESSES DURING THE YEAR 2020-21

2. PRODUCT IMPROVEMENTS

3. 3 PRODUCT IMPROVEMENTS Project Observations Improvements done T90 Failures were observed in Additional Distribution Box (ADB) of T-90 ALG System supplied to HVF, Avadi . On further analysis, it was found that Transistor Q7, Q15, Q23 & Q31 used in the Amplifier Circuits of Amplifier PCB (PCB A2 - 4 Amplifiers) and Transistor Q10 in Control Circuit 2 PCB (PCB A3 - 1 Amplifier) was failing during Short Circuit / Over load Protection Test. By introducing Test Field Resistors instead of Fixed Values for Resistors R14, R28, R42 & R56 in Amplifier PCB and for Resistor 26 in Control Circuit 2 PCB, the Amplifier Circuits were withstanding the Short Circuit / Over load Protection Test which was a Class `C’ System level tests. Accordingly the supplied ADBs were taken back from HVF, Short Circuit / Over load Protection Test is carried out by selecting appropriate Test Field Resistors / by changing the defective Transistor mentioned above. After this exercises there were no failures.

4. 4 PRODUCT IMPROVEMENTS Project Observations Improvements done T72 In T-72 Gun Setting Device (GSD), Contacts of the Brush Assembly were breaking , resulting in failure of the item. On further analysis, it was found that the Spot Welding of the Contacts is not sufficient to withstand continuous operation of GSD. The welding process was changed to Laser Fusion Welding after which there were no failures. R174 In R174 Mk II project, failures were observed in the Chest Switch Cable 1.2M and 2.2 M while doing Class `C’ tests. In order to ensure the reliable operation following improvements were incorporated: Switch Lever, thickness is increased from 1mm to 1.2mm. Semi Loctite applied in the Switch lever mounting screw. Insulator is added in between the Screw and Switch to Lift the Switch. Switch mounting Screws changed from SST-M2x10 to M2x14

5. 5 PRODUCT IMPROVEMENTS Project Observations Improvements done BOFORS & DHANUSH During advance sample evaluation of Connection Box Loader (C18) , problem observed during Rain test. Connectors mounted from inside & Casting drawings modified. Casting material changed from LM6 to LM25 (superior material). All evaluation tests repeated and found ok. This done in BOFORS C18 will be implemented in C18 of DHANUSH also. TLR/FLR In TLR/FLR MK-II Slewing system, when system is required to be used in Manual mode entire slewing system was switched off. Wiring change is done in Servo Drive Amplifier (Part no : 1750 008 953 74) to enable manual slewing without switching off full system . TLR/FLR During LCP2403 card Testing (Part no: 1753 022 018 18), it was observed PAL ICs failing frequently. The existing PAL IC (4374 750 503 05) found obsolete. Obsolete ICs has been replaced with New PAL IC (4374 137 701 67)

6. 6 PRODUCT IMPROVEMENTS We have received STPO for ANLS (AERV MK-II) ,Qty-53 Nos which are to be supplied in short period. Already Qty-02 system supplied to BEL- Pune by D&E (BEL-Chennai). ANLS (AERV MK-II) has come to production for the first time & In this ACDU (P/N: 1750 010 044 02) is a new item. During the first production batch of Qty-06 ACDU, Crack was observed in Display touch screen controller of ACDU. Out of 6 No’s, 3 No’s display touch screen got cracked 1 No’s in Testing after vibration. When back traced found 2-No’s cracked after Assembly. After Detail study & analysis modification were done inside ACDU by adding rubber cushions behind the touch screen display. Also New fixture was developed for conducting vibration tests. After the modification 8 No’s of ACDU were manufactured , tested, offered and cleared by Inspection Agency. In this batch no cracks observed in touch screen display.

7. 7 PRODUCT IMPROVEMENTS We have received Qty-16 No’s of CDU Processor card P/N: 1753 032 001 42 of ALNS for testing during March 2021. Out of 16, Qty-09 were tested and found OK and Qty-07 were found defective. The defective PCB’s were found OK during bench testing, but failing when integrated in CDU.CDU display goes OFF. On defect analysis it is observed that, in SRAM U1, U2, and U19 & U20 P/N: 4374 755 401 55 IC’s O/P signals problem was observed. All the four IC’s have same part number, when tested individually the O/P signals are found OK, but when integrated timing issue was observed. On further analysis , it was found that these IC’s are procured from different suppliers M/s Pyramid semiconductor, M/s Microchip Inc, M/s Austin electronics Inc etc having their own MPN’s and all are acceptable as per SAP. When these different manufacturer IC’s are mixed and soldered in place of U1, U2 , U19 & U20 timing issue arises and CDU display goes OFF. Since all the MPNs are acceptable in SAP, it is passing through assembly& inspection stage but failing in testing stage. After replacing the all four IC with same MPN, the PCBs found OK. As a CAPA action , notes were added to use same MPN ICs for U1,U2 ,U19 & U20 in GA & PL of CDU Processor card P/N: 1753 032 001 42 to avoid the repetition of problems in future .

8. PROCESS IMPROVEMENTS

9. 9 PROCESS IMPROVEMENTS Project Observations Improvements done BMP-II Failure of Insulation Resistance and Di Electric Test in Control Gear Gun Stabilizer System Soldering on Cosine terminals improved by carrying out Pigtail Wiring. WD Corrected accordingy . Fig: Cosine Potentiometer contacts by introducing Pigtail Wiring to reduce IR failures

10. 10 PROCESS IMPROVEMENTS Project Observations Improvements done BMP-II Failure of Insulation Resistance and Di Electric Test in Control Gear Gun Stabilizer System (ii) The process of cable branching, shield preparation, proper insulation of wires with black tape & routing of the cable form with cable ties at appropriate places was explained to sub vendor. Fig: Improved Shield Wires

11. 11 PROCESS IMPROVEMENTS Project Observations Improvements done BMP-II Failure of Insulation Resistance and Di Electric Test in Control Gear Gun Stabilizer System (iii) Proper fastening of cable form near Cosine Potentiometer

12. 12 PROCESS IMPROVEMENTS Project Observations Improvements done BMP-II Failure of Insulation Resistance and Di Electric Test in Control Gear Gun Stabilizer System (iii) Proper Cleaning of J1 Connector pins & LED Assy , switch contacts and potentiometer Fig: Cleaning of Connectors before putting sleeve and blowing of hot air Fig: Switch Contacts and Potentiometer

13. 13 PROCESS IMPROVEMENTS Alignment Fixture for Gun Setting Device of T-72 manufactured to avoid parallax error while taking measurements. HVF, Avadi reported Leakages in many of the Actuating Cylinder of T-72. An additional Bench Level Testing of Elevation Hydraulics System called as `Run In Test Stage' was established and all the Elevation Hydraulics System is subjected to Running for 1 Hour in this Test stand before Testing in the Turret Test Stand. This additional test will ensure the continuous movement of the Piston of the Actuating Cylinder upto both the extremes thereby ensuring the reliability of the System. Any failures in Seals of the Actuating Cylinder will be detected at BEL and a failure at Customer end is avoided. HVF, Avadi was rejecting T-72 Gyro Unit for Unevenness movement of turret in throw over speed. The issue was jointly studied by BEL, HVF & CQA (AVL) at BEL Turret Test Stand & in the Tank

14. 14 PROCESS IMPROVEMENTS BEL , Chennai received Supply Order from DGOS, New Delhi for the supply of Qty 146 Nos of T-90 Amplidyne Unit . So far this item was tested in the Horizontal & Inclined Turret Test Stand and supplied to HVF. Since this is a Spare order, a separate Test Set up was made using a Test Jigs & Loading Rheostats for Testing the Amplidyne as per ATP. Instead of keeping the Amplidyne under test in the Ground, a Fixture was fabricated to arrest the self movement during High speed rotation. Previously the Motor RPM was checked by removing the Fan cover which was unsafe, a technological cover with provision for observing the speed of the Amplidyne motor introduced. Accordingly, ATP was also modified. The entire set up was made to carry out the test measurements easily and safely .

15. 15 PROCESS IMPROVEMENTS 155 mm Dhanush / Bofors Project Time Module PCB used in Connection Box Loader (C18) was tested only at PCB level. Post assembling and wiring, its functionality was not checked at Unit Level. Moreover, there are 366 wire connections in the unit and inspecting the same as per Wire List requires removing all the 31 Nos. of relays in order to access the relay pins. A Test Jig was made to test all the relays and new test procedures were made to test the Time Module PCB at Unit Level. By using this Test Jig, all the wiring connections to the relays are covered and hence it ensures that all the wirings are checked, thereby saving Inspection & Testing man hours. Fig: C18 Test setup

16. 16 PROCESS IMPROVEMENTS 155 mm Dhanush / Bofors Project For Insulation Resistance (IR) & Di-electric Strength (DE) checks of Connection Box Loader C18, pins for all the connectors to be checked wrt body. This takes 25 minutes for each unit. A mating connector has been used for shorting all pins together in the connector for checking wrt body. It takes less than 10 minutes. Fig: Mating Connectors

17. 17 PROCESS IMPROVEMENTS 155 mm Dhanush / Bofors Project Time Module PCB of Connection Box Loader (C18) is to be tested for ESS for 4 hrs. Only 1 No. of Test cable was available to test the Time Module PCB at a time. New Test Jig was made to simultaneously connect 5 PCBs for testing in ON condition during ESS Tests for 4 hrs, thereby reducing Testing Cycle time . Fig: Time Module PCB Test Setup

18. 18 Project Observations Improvements done ALNS for CAR ( Rohini -AK) Test for testing back up time provided by Capacitor Box Assy in integrated mode be specified / included in the ATP New tests added in ATP and submitted for approval to MSQAA on 27.01.2021 L-70 Subunit Level : SMC test jig incorporation in the ATP. The modified ATP submitted to CQAR for approval. Separate test procedure for Optronic Pedestal to be introduced. Test Procedure for Optronic Pedestal submitted to CQAR for approval. MRLS items to be offered with final packing case and with required information. Packing of MRLS modules has been standardized with proper stacking and ESD marking introduced on modules to avoid missing of components/to ensure quantity and quality of items. PROCESS IMPROVEMENTS BASED ON CUSTOMER FEEDBACK

19. 19 Project Observations Improvements done L-70 Gun Level : TMR has check OK/Not Ok observation for certain parameters for ATP checks. TMR is updated to enter readings during the ATP checks. No checks for power control panel & fuse panel. Checklist points were added to include the readings & functionality of power control panel & fuse panel. Gun rotation in Tr & El was not smooth in some guns Gun tuning parameters were ensured for smooth rotation in Tr & El Measuring of Firing Magnet Solenoid Coil resistance to ensure proper functioning of firing circuit. Measuring of Firing Magnet Solenoid Coil resistance to ensure proper functioning of firing circuit. PROCESS IMPROVEMENTS BASED ON CUSTOMER FEEDBACK