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OSG Screw Thread Insert STI Tap: Spiral Fute, 9/16"-18 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, 9/16"-18 UNF, H4 / 2B-3B, 4 Flute

The OSG Screw Thread Insert STI Tap (MPN 30203501) is a spiral-flute tap for steel and stainless steel, sized 9/16"-18 UNF with an H4 / 2B-3B tolerance and a bottoming chamfer. It features 4 flutes and is designed…

SKU 3G-OTH-244327

Brand
OSG
Item
Screw Thread Insert STI Tap: Spiral Fute, 9/16"-18 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
30203501
Type
H4 / 2B-3B, Bottoming Chamfer
Flute
4
UNF
9/16"-18
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OSG Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The OSG Screw Thread Insert STI Tap (MPN 30203501) is a spiral-flute tap for steel and stainless steel, sized 9/16"-18 UNF with an H4 / 2B-3B tolerance and a bottoming chamfer. It features 4 flutes and is designed for threading holes to accept screw thread inserts.

Frequently Asked Questions

What is the OSG 30203501 STI tap used for?

The OSG 30203501 is a spiral-flute STI tap designed for threading holes in steel and stainless steel before installing screw thread inserts. Its bottoming chamfer allows threading close to the bottom of blind holes, making it ideal for repair and production work in automotive, aerospace, and general manufacturing.

What are the specifications of the OSG 30203501 STI tap?

This OSG tap has a 9/16"-18 UNF thread size, H4 / 2B-3B tolerance, 4 flutes, and a bottoming chamfer. It is a spiral-flute STI tap for steel and stainless steel. The manufacturer part number is 30203501. It is designed for use with screw thread inserts to restore or strengthen threads.

Where to buy OSG taps in worldwide?

3G Electric supplies OSG taps like the 30203501 to customers worldwide. As a global industrial distributor, we handle full logistics, customs clearance, and delivery to your location. Contact us for availability and lead time. We source and deliver genuine OSG tooling for manufacturing and maintenance applications.

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

Select an STI tap that matches the insert's thread size and pitch, such as 9/16"-18 UNF. Choose a spiral-flute design for steel or stainless steel to clear chips from blind holes. The H4 / 2B-3B tolerance ensures proper fit. OSG taps like the 30203501 are engineered for consistent thread quality in demanding materials.

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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