{"product_id":"heli-coil-7552-7-thread-insert-tool-7-16-20-unf-prewinder","title":"Heli-coil 7552-7 Thread Insert Tool 7\/16-20 Unf Prewinder","description":"\u003ch3\u003eProduct Description\u003c\/h3\u003e\n\u003cp\u003eThe HELI-COIL 7552-7 is a Type II prewinder hand installation tool designed for installing 7\/16-20 UNF thread inserts without power equipment. The tool accepts both free-running and locking thread insert types, making it a versatile addition to any shop or field repair kit. The prewinder body measures 25\/32 inches in diameter, with an overall prewinder length of 5.25 inches and a spinner diameter of 3-23\/32 inches. HVAC technicians, plumbers, electricians, and general maintenance pros use this tool when restoring stripped or damaged threads in metal components using helical wire thread inserts.\u003c\/p\u003e\n\u003cp\u003eThis tool is used in applications where hand-driven thread insert installation is required, such as tapped hole repair in aluminum housings, cast iron components, or other base materials where thread inserts restore original thread integrity. The 7\/16-20 UNF size is common in fastener-critical assemblies found in HVAC equipment, pumps, compressors, and mechanical systems. It is suited for both shop bench work and field service where powered installation tools are unavailable or impractical.\u003c\/p\u003e\n\u003ch4\u003eKey Features\u003c\/h4\u003e\n\u003cul\u003e\n  \u003cli\u003eInstalls 7\/16-20 UNF thread inserts by hand without power tools\u003c\/li\u003e\n  \u003cli\u003eCompatible with both free-running and locking insert types\u003c\/li\u003e\n  \u003cli\u003eType II prewinder design for controlled, accurate insert placement\u003c\/li\u003e\n  \u003cli\u003ePrewinder body diameter of 25\/32 inches for stable grip and alignment\u003c\/li\u003e\n  \u003cli\u003eSpinner diameter of 3-23\/32 inches for comfortable hand operation\u003c\/li\u003e\n  \u003cli\u003eOverall prewinder length of 5.25 inches suits standard insert depths\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch4\u003eCompatibility\u003c\/h4\u003e\n\u003cp\u003eDesigned for use with free-running and locking helical wire thread inserts in the 7\/16-20 UNF thread size, consistent with HELI-COIL and equivalent insert systems requiring a Type II prewinder installation tool.\u003c\/p\u003e\n\u003ch4\u003eInstallation Notes\u003c\/h4\u003e\n\u003cp\u003eThis tool is hand-operated and requires no power source. Before installing a thread insert, verify the parent hole has been drilled and tapped to the correct insert tap size for the 7\/16-20 UNF specification. Ensure the work piece is secured and the threaded hole is clean and free of debris before loading the insert onto the prewinder. Follow the insert manufacturer's installation procedure for proper seating depth and tang break-off where applicable.\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\u003eMinimum Thread Size\u003c\/strong\u003e: 7\/16-20\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eThread Standard\u003c\/strong\u003e: UNF\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: 5.25 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: 7552-7\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"HELI-COIL","offers":[{"title":"Default Title","offer_id":52070412124466,"sku":"7552-7","price":232.44,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0270\/4519\/9983\/files\/4288174c9e2abd89315c4733c7b2fbd4.jpg?v=1790048421","url":"https:\/\/voomisupply.com\/products\/heli-coil-7552-7-thread-insert-tool-7-16-20-unf-prewinder","provider":"Voomi Supply","version":"1.0","type":"link"}