Carr Lane heavy duty key inserts are general-purpose threaded inserts with a thick, heavy-duty thread wall, suitable for most applications. Heavy-duty Key Inserts are ideal for thread reinforcement, especially when the mating stud or bolt will be removed frequently. They provide strong, permanent steel threads in almost any parent material – ferrous, non-ferrous, or non-metallic. Heavy-duty Key Inserts are also well suited for quick repair of stripped, damaged, or worn threads. Locking keys positively prevent the insert from rotating. Browse the complete line of heavy duty key inserts from Carr Lane in our online catalog.
Heavy-duty steel Key Inserts are available in a wide range of inch and metric ID thread sizes. The following inch sizes are shown on this page:
#10-24 to 1-1/2"-6 NC Coarse
#10-32 to 1-1/2"-12 UNF Fine
Body > 1215 steel, black oxide finish. Keys > 302 stainless steel. DFARS and RoHS compliant.
Heavy-duty stainless steel Key Inserts are available in a wide range of inch and metric ID thread sizes. The following inch sizes are shown on this page:
#10-24 to 3/4-10 NC Coarse
#10-32 to 1/2-20 UNF Fine
Body > 1215 steel, black oxide finish. Keys > 302 stainless steel. DFARS and RoHS compliant.
Heavy-duty steel Key Inserts are available in a wide range of inch and metric ID thread sizes. The following metric sizes are shown on this page:
M16 to M24 Metric Coarse
M16x1.5 to M24x2 Metric Fine
Please note, metric sizes smaller than those above are available only in stainless steel (see Related Products below):
M5 to M12 Metric Coarse
M8x1 to M12x1.25 Metric Fine
Body > 303 stainless steel. Keys > 302 stainless steel. RoHS compliant.
Key Inserts are often used to reinforce tapped holes in aluminum tooling plates.
Repair Kits contain an installation tool and several inserts of a given size.
Key Inserts are installed using standard drills and taps, but the required tap-drill size is slightly larger than normal for that OD thread size. See Installation Data table below for the appropriate tap-drill size. Locking keys must be driven down into the parent material during installation, providing a positive mechanical lock against rotation. See tables below for installation tools, or for repair kits containing an installation tool and several Key Inserts of a given size.
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