Additional Manufacturer Narrative · 1
AT THE DISTRIBUTOR'S REQUEST, WE REVIEWED THE PRODUCTION DOCUMENTS, CARRIED OUT A THOROUGH EXAMINATION ON THE INSTRUMENT AND CONDUCTED A TREND ANALYSIS ACCORDINGLY. RESULTS: OF INSTRUMENT PART NO. 600-147 WITH LOT #110899, A TOTAL QUANTITY OF 40 INSTRUMENTS WERE MFG IN MARCH 1999 AND SHIPPED TO JARIT AGAINST THE FOLLOWING INVOICES: # 997170 OF 1999; # 997349 OF 1999; # 997416 OF 1999; #997584 OF 1999 AND # 997778 OF 1999. WITHIN THE PAST FIVE YEARS, A TOTAL OF 387 INSTRUMENTS OF PART NO. 600-147 HAVE BEEN SUPPLIED TO JARIT. A TREND ANALYSIS CONDUCTED BY US BASED ON A COMPLAINT EVAL DID NOT REVEAL ANY STRIKING FEATURES INDICATING AN ACCUMULATIVE OCCURRENCE OF THIS TYPE OF NONCONFORMANCE. WITHIN THE PAST FIVE YEARS, THERE HAVE NEITHER BEEN ANY COMPLAINTS NOR ANY MDR REPORTING OF THE DAMAGE DESCRIBED. UPON TRACING BACK THE LOT NUMBER IN QUESTION, WE FOUND THAT BOTH THE CORRECT MATERIAL AND COMPONENTS HAD BEEN USED AND THAT THE INSTRUMENT IS IN CONFORMANCE WITH THE PRODUCT SPECS. AN EXAMINATION OF THE INSTRUMENT REVEALED THE FOLLOWING: THE JAW PART BROKE OFF; A HARDNESS TEST PERFORMED ON THIS JAW RESULTED IN A VALUE OF HRC 47 (WITH HRC 44-48 BEING SPECIFIED). A MICROSCOPIC EXAMINATION OF THE JAW PART REVEALED CORROSION BOTH ON THE DRAW ROD AND IN THE HINGE AREA. THE FRACTURED SURFACE, TOO, SHOWS SIGNS OF CORROSION. CONCLUSION: THE INSTRUMENT IS IN ACCORDANCE WITH THE SPECS. WE HAVE NO EXPLANATION AS TO WHAT EXACTLY THIS DAMAGE WAS CAUSED BY. BASED ON THE CORROSION SEEN ON THE FRACTURED SURFACE, WE SUSPECT THE JAW TO HAVE BEEN PRE-DAMAGED BY A FINE HAIRLINE CRACK. HAIRLINE CRACKS MAY RESULT FROM AN OVERSTRESSING OR A MISUSE OF AN INSTRUMENT DURING USE. SUCH CRACKS ARE PRONE TO BUILDING CORROSION, AS A RESULT OF WHICH THE CRACK INCREASES OVER TIME. ACCORDINGLY, THIS LEADS TO A GRADUAL DECREASE IN STABILITY WHICH ULTIMATELY MAKES THE JAW BREAK AT THE SMALLEST STRESS ACTING UPON IT. CORRECTIVE AND PREVENTIVE ACTION: BASED ON OUR EXAMINATION, WE HAVE NO INDICATION WHATSOEVER THAT EITHER THE DESIGN, MATERIAL OR MFG PROCESS, OR ANY CIRCUMSTANCES WITHIN OUR SPHERE OF INFLUENCE HAVE GIVEN CAUSE FOR ANY CORRECTIVE OR PREVENTIVE ACTION TO BE INITIATED BY US. NO ACTION WILL THEREFORE BE TAKEN BY US.