OSG Screw Thread Insert STI Tap: Spiral Fute, 1"-12 UNF, H4 / 2B-3B
SKU 3G-OTH-281081
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Frequently Asked Questions
What is the OSG Screw Thread Insert STI Tap used for?
This OSG spiral-flute STI tap is used to cut internal threads in multiple materials for installing screw thread inserts. It is commonly applied in aerospace, automotive, and general manufacturing where strong, replaceable threads are required in aluminum, steel, and cast iron.
What are the specifications of the OSG STI Tap 31504201?
The OSG STI tap has a 1"-12 UNF thread size, H4 / 2B-3B tolerance, and 4 flutes with a spiral flute design. The manufacturer part number is 31504201. It is designed for multiple materials and produces threads that accept standard screw thread inserts.
Where to buy OSG STI Tap 31504201 worldwide?
You can source the OSG STI Tap 31504201 through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to worldwide destinations. Contact us for availability and lead time on this spiral-flute tap.
How to select the correct OSG STI tap for a thread insert?
Select an OSG STI tap based on the thread size and pitch of the insert, such as 1"-12 UNF. Ensure the tap tolerance (H4 / 2B-3B) matches the required thread class. For multiple materials, a spiral-flute design helps evacuate chips. Always verify the insert manufacturer's recommended tap drill size.
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Common applications for OSGOSG Products
3G Electric supplies OSG spiral-flute sti taps for multiple materials. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.















