Updates: d4 batch number, and d9 product receipt date.The device was returned to the manufacturer and evaluated at tek park for distal tip separation.An investigation of the device manufacturing records was conducted by the manufacturer for the lot # of the device in question.No non-conformances were reported.All device history records (dhr) are reviewed and released according to documented procedures and a device is not released if it does not meet requirements or is nonconforming.Additionally, historical scrap rates were reviewed with no increase observed in scrap related to the complaint issue.Previous investigations performed against devices returned with distal braze failures identified improvement opportunities following a review of the tube sub assembly test procedure work instruction (wi), the brazing procedure wi, and the brazed joint buffing wi.While the tube subassembly joint is 100% percent tested with a torsional force, there was no requirement for applying a bending force to the joint.Therefore, a manual bend test was added to the wi.Additionally, a review of the torque test fixture and accompanying wi, noted the potential for the tube to slip inside the collet during inspections allowing for a defective part to potentially pass this test.The tube sub assembly test procedure was further updated to note this potential failure mode and to define the process for cleaning the parts and fixture/collet with alcohol prior to use.A review of the brazing procedure wi revealed that the glass tube was too short to effectively seal the brazing area off from the surrounding environment.Without a proper seal the brazing area could have insufficient argon present to facilitate effective brazing.The brazing procedure wi was updated to include a check for this condition prior to brazing.Additionally, the supplier updated the wi to optimize the order of operations of when flux is applied, the soldering ring is assembled, and the tube is loaded.This change ensured that flux would be present throughout the entire joint space and allow for proper solder travel.Furthermore, a functional review and visual examination of the nest, which the tube sub assembly sits into, was performed.This review revealed that the two argon access holes were clogged.Therefore, the associated preventative maintenance activities were updated to monitor the access holes and prevent a recurrence of buildup.Finally, the supplier updated the brazed joint buffing wi to note the potential failure mode of excessive buffing, which could remove too much material and weaken the joint.The visual inspection at tek park noted nicks, scratches and jaw assembly was broken and disassembled from the jaw housing.Repair information was not available.Functional testing revealed that the instrument function was not smooth and consistent, and there was jaw misalignment.The complained failure of the device was confirmed.Based on prior evaluations of complaint devices reported with a failure mode of distal braze break/separation, this event likely occurred due to inadequacies in the defined production process which limited the device performance.Aesculap inc.Opened a corrective action/preventive action (capa) for further evaluation of the design transfer of this device.
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