OSG 1/2"-20 UNF Spiral-Flute STI Tap, H3 / 2B-3B, Bottoming Chamfer, 4 Flutes
The OSG Screw Thread Insert STI Tap is a spiral-flute tap designed for threading holes to accept screw thread inserts. This specific model features a 1/2"-20 UNF thread size, an H3 / 2B-3B tolerance class, a…
SKU 3G-OTH-273420
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Product Description
The OSG Screw Thread Insert STI Tap is a spiral-flute tap designed for threading holes to accept screw thread inserts. This specific model features a 1/2"-20 UNF thread size, an H3 / 2B-3B tolerance class, a bottoming chamfer, and 4 flutes (MPN 8018400).
Frequently Asked Questions
What is an OSG spiral-flute STI tap used for?
An OSG spiral-flute STI tap is used to cut internal threads for screw thread inserts in materials that produce stringy chips, such as aluminum and low-carbon steel. The spiral-flute design evacuates chips upward, making it ideal for blind-hole applications. This tap is commonly used in automotive, aerospace, and general manufacturing.
What are the specifications of the OSG 8018400 STI tap?
The OSG 8018400 is a spiral-flute STI tap with a 1/2"-20 UNF thread, H3 / 2B-3B tolerance, 4 flutes, and a bottoming chamfer. It is designed for screw thread insert installation. The H3 / 2B-3B designation ensures precise thread fit for insert applications.
Where to buy OSG taps in worldwide?
You can source OSG taps worldwide through 3G Electric, a global industrial equipment distributor. We handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead times on the OSG 8018400 STI tap and other OSG tooling.
How to select the correct STI tap for a thread insert?
Select an STI tap that matches the insert's thread size and pitch, such as 1/2"-20 UNF. Choose a spiral-flute design for blind holes or a spiral-point design for through holes. The chamfer type—bottoming for threads near the hole bottom—and tolerance class (e.g., H3 / 2B-3B) must align with the insert manufacturer's recommendations.
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3G Electric supplies OSG spiral-flute sti taps. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.
