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OSG Screw Thread Insert STI Tap: Spiral Point, 7/8"-14 UNF, H4 / 2B-3B, 4 Flute - Spiral-Point STI Taps for Multiple Materials
OSGSpiral-Point STI Taps for Multiple Materials

OSG Screw Thread Insert STI Tap: Spiral Point, 7/8"-14 UNF, H4 / 2B-3B, 4 Flute

The OSG Screw Thread Insert STI Tap is a spiral-point tap designed for threading multiple materials, featuring a 7/8"-14 UNF thread size, H4 / 2B-3B tolerance, 4 flutes, and a plug chamfer (MPN 31403908).

SKU 3G-OTH-284688

Brand
OSG
Item
Screw Thread Insert STI Tap: Spiral Point, 7/8"-14 UNF, H4 / 2B-3B, 4 Flute
Category
Spiral-Point STI Taps for Multiple Materials
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Technical Specifications

OSG
Manufacturer Part Number
31403908
Type
H4 / 2B-3B, Plug Chamfer
Flute
4
UNF
7/8"-14
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OSG Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

The OSG Screw Thread Insert STI Tap is a spiral-point tap designed for threading multiple materials, featuring a 7/8"-14 UNF thread size, H4 / 2B-3B tolerance, 4 flutes, and a plug chamfer (MPN 31403908).

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 multiple materials to accept helical wire thread inserts. It is commonly used in aerospace, automotive, and industrial maintenance applications where stripped threads must be repaired or reinforced with a threaded insert.

What are the specifications of the OSG STI Tap 31403908?

The OSG STI Tap 31403908 is a spiral-point, plug-chamfer tap with 4 flutes. It cuts a 7/8"-14 UNF thread and is ground to H4 / 2B-3B tolerance class. This tap is designed for use with screw thread inserts in multiple materials.

Where to buy OSG STI Tap 31403908 worldwide?

3G Electric supplies the OSG STI Tap 31403908 to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for a quote and lead time on this spiral-point tap for thread insert applications.

How to select the correct STI tap for a thread insert?

Select an STI tap that matches the thread size and pitch of the insert, such as 7/8"-14 UNF. Use a plug-chamfer tap for through holes and a bottoming-chamfer for blind holes. The H4 tolerance ensures proper fit for 2B-3B class threads in the parent material.

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-point sti taps for multiple materials. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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