{"product_id":"heli-coil-7551-7-thread-insert-tool-7-16-14-unc-prewinder","title":"Heli-coil 7551-7 Thread Insert Tool 7\/16-14 Unc Prewinder","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe HELI-COIL 7551-7 is a hand-operated thread insert installation tool designed for installing 7\/16-14 UNC wire thread inserts. It uses a Type II Prewinder mechanism that compresses the insert for clean, accurate engagement into the receiving hole. The tool accepts both free-running and locking insert types, making it suitable for a range of repair and assembly applications. The prewinder body measures 25\/32 inches in diameter and the spinner measures 3-23\/32 inches in diameter. This is a hand-use tool intended for technicians and machinists performing thread repair or new thread installation on equipment and assemblies in the field or shop.\u003c\/p\u003e\n\u003cp\u003eThis tool is used wherever HELI-COIL or compatible wire thread inserts in the 7\/16-14 UNC size are installed. Common applications include thread repair on machinery, engine components, structural fastener bosses, and industrial equipment. It is suited for both production assembly environments and field repair scenarios where a hand tool is preferred or required. The prewinder design ensures the insert coil is properly wound down before engagement, reducing installation errors and protecting threads in the parent material.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003eType II Prewinder mechanism compresses insert coil for accurate, controlled installation\u003c\/li\u003e\n  \u003cli\u003eCompatible with both free-running and locking wire thread inserts\u003c\/li\u003e\n  \u003cli\u003eDesigned for 7\/16-14 UNC thread size\u003c\/li\u003e\n  \u003cli\u003ePrewinder body diameter: 25\/32 inches\u003c\/li\u003e\n  \u003cli\u003eSpinner diameter: 3-23\/32 inches\u003c\/li\u003e\n  \u003cli\u003eHand-operated  -  no power source required, suitable for field use\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003eDesigned for use with free-running and locking wire thread inserts in the 7\/16-14 UNC thread standard. Intended as an OEM-matched installation tool for HELI-COIL 7\/16-14 UNC thread insert series.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003eInstallation is performed by hand and does not require power tools. Before installing thread inserts, ensure the parent hole has been properly drilled and tapped to the correct HELI-COIL tap size for 7\/16-14 UNC threads. Load the insert into the prewinder, align with the tapped hole, and advance the spinner to drive the insert to the correct depth. Follow the insert manufacturer's installation depth specifications for the application.\u003c\/p\u003e\n\u003ch4\u003eTechnical Specifications\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eTool Type\u003c\/strong\u003e: Hand Installation Tool, Type II Prewinder\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThread Size\u003c\/strong\u003e: 7\/16-14\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThread Standard\u003c\/strong\u003e: UNC\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eInsert Compatibility\u003c\/strong\u003e: Free-Running and Locking\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePrewinder Body Diameter\u003c\/strong\u003e: 25\/32 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eSpinner Diameter\u003c\/strong\u003e: 3-23\/32 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003ePrewinder Length\u003c\/strong\u003e: 7\/16 inches\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eUNSPSC Code\u003c\/strong\u003e: 23291800\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eStandard Information\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eBrand\u003c\/strong\u003e: HELI-COIL\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eManufacturer Part Number\u003c\/strong\u003e: 7551-7\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"HELI-COIL","offers":[{"title":"Default Title","offer_id":51972948820274,"sku":"7551-7","price":231.61,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/d2244c37caae28806c31065eba45f234.jpg?v=1789971348","url":"https:\/\/voomisupply.com\/products\/heli-coil-7551-7-thread-insert-tool-7-16-14-unc-prewinder","provider":"Voomi Supply","version":"1.0","type":"link"}