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OSG 1/4"-28 UNF Spiral-Flute STI Tap for Steel & Stainless Steel - Spiral-Flute STI Taps for Steel & Stainless Steel
OSGSpiral-Flute STI Taps for Steel & Stainless Steel

OSG 1/4"-28 UNF Spiral-Flute STI Tap for Steel & Stainless Steel

The OSG Screw Thread Insert STI Tap (Spiral Flute) is a 1/4"-28 UNF bottoming-chamfer tap with an H3 / 2B-3B tolerance class and 3 flutes, designed for threading holes that will accept screw thread inserts in steel…

SKU 3G-OTH-244194

Brand
OSG
Item
1/4"-28 UNF Spiral-Flute STI Tap for Steel & Stainless Steel
Part Number
0146308
Category
Spiral-Flute STI Taps for Steel & Stainless Steel
Available to Order
Also known as:0146308OSG
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Technical Specifications

OSG
Manufacturer Part Number
0146308
Type
H3 / 2B-3B, Bottoming Chamfer
Flute
3
UNF
1/4"-28

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OSG Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The OSG Screw Thread Insert STI Tap (Spiral Flute) is a 1/4"-28 UNF bottoming-chamfer tap with an H3 / 2B-3B tolerance class and 3 flutes, designed for threading holes that will accept screw thread inserts in steel and stainless steel. As a specialist in industrial solutions across 14 departments—including machining, electrical, and power transmission—3G Electric sources and supports this OSG tap alongside brands like Schneider, ABB, and SKF, with deep expertise in combustion, pumps, and controls.

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 in steel and stainless steel for screw thread inserts. It creates threads that accept a helical coil insert, commonly used in aerospace, automotive, and industrial maintenance to repair or strengthen tapped holes.

What are the specifications of the OSG 1/4"-28 UNF STI tap?

The OSG STI tap has a 1/4"-28 UNF thread size, H3 / 2B-3B tolerance, 3 flutes, and a bottoming chamfer. It is designed for spiral-flute tapping in steel and stainless steel. The manufacturer part number is 0146308.

Where to buy OSG taps in worldwide?

3G Electric supplies OSG taps worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your site. Contact us for availability and lead time on the OSG 1/4"-28 UNF STI tap (MPN 0146308).

How to select the correct OSG STI tap for a repair job?

Select an OSG STI tap that matches the thread size and pitch of the insert you plan to install. For steel or stainless steel, use a spiral-flute design with a bottoming chamfer for blind holes. Verify the tap tolerance (e.g., H3 / 2B-3B) matches your required thread class.

Used in

Common applications for OSG
Automotive engine block production — OSG micro drill bits for oil gallery and coolant passage drilling in cast iron
Medical device manufacturing — OSG micro drill bits for drilling bone screw pilot holes in stainless steel implants
Aerospace component machining — OSG micro drill bits for fastener holes in titanium alloy structural parts
Mold and die making — OSG micro drill bits for cooling channel drilling in hardened tool steel (HRC 45-50)
Electronics enclosure fabrication — OSG micro drill bits for precision holes in aluminum alloy housings (with appropriate coating selection)
General engineering job shops — OSG micro drill bits for small-diameter hole drilling in mild steel and alloy steel parts
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OSG Products

3G Electric supplies OSG spiral-flute sti taps for steel & stainless steel. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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