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OSG Screw Thread Insert STI Tap: Spiral Fute, 1/2"-20 UNF, H4 / 2B-3B, 4 Flute - Spiral-Flute STI Taps for Steel & Stainless Steel
OSGSpiral-Flute STI Taps for Steel & Stainless Steel

OSG Screw Thread Insert STI Tap: Spiral Fute, 1/2"-20 UNF, H4 / 2B-3B, 4 Flute

The OSG Screw Thread Insert STI Tap (MPN 0147908) is a spiral-flute tap for steel and stainless steel, sized 1/2"-20 UNF with a H4 / 2B-3B tolerance and bottoming chamfer. It features 4 flutes and is designed for…

SKU 3G-OTH-244334

Brand
OSG
Item
Screw Thread Insert STI Tap: Spiral Fute, 1/2"-20 UNF, H4 / 2B-3B, 4 Flute
Category
Spiral-Flute STI Taps for Steel & Stainless Steel
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Technical Specifications

OSG
Manufacturer Part Number
0147908
Type
H4 / 2B-3B, Bottoming Chamfer
Flute
4
UNF
1/2"-20
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OSG Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The OSG Screw Thread Insert STI Tap (MPN 0147908) is a spiral-flute tap for steel and stainless steel, sized 1/2"-20 UNF with a H4 / 2B-3B tolerance and bottoming chamfer. It features 4 flutes and is designed for threading holes to accept screw thread inserts.

Frequently Asked Questions

What is an OSG Screw Thread Insert STI Tap used for?

An OSG Screw Thread Insert STI Tap cuts internal threads in steel and stainless steel to accept helical wire thread inserts. It is commonly used in aerospace, automotive, and industrial maintenance to repair or reinforce stripped threads without replacing the parent component.

What are the specifications of the OSG STI Tap 1/2"-20 UNF?

This OSG STI Tap has a 1/2"-20 UNF thread, H4 / 2B-3B tolerance, 4 flutes, and a bottoming chamfer. It is designed for spiral-flute tapping in steel and stainless steel. The manufacturer part number is 0147908.

Where to buy OSG STI Taps worldwide?

3G Electric supplies OSG STI Taps worldwide. We handle full logistics, customs clearance, and delivery to your facility. Contact us for pricing and lead time on this 1/2"-20 UNF spiral-flute tap (MPN 0147908).

How to select the correct STI tap size for a thread repair?

Select an STI tap that matches the original thread size and pitch, such as 1/2"-20 UNF. Use a bottoming chamfer for blind holes and a spiral-flute design for steel or stainless steel. Always verify the tap tolerance (e.g., H4 / 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

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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