HELI-COILGeneral Purpose STI Taps

HELI-COIL Screw Thread Insert STI Tap: Straight Fute, 1/4"-28 UNF, H2 / 3B, 3 Flute

The HELI-COIL Screw Thread Insert STI Tap is a straight flute, general-purpose tap designed for installing HELI-COIL screw thread inserts. This 1/4"-28 UNF tap features an H2 / 3B tolerance class, a plug chamfer, and…

SKU 3G-OTH-262006

Also listed as: 4 FPB · 4-FPB

Brand

HELI-COIL

Item

Screw Thread Insert STI Tap: Straight Fute, 1/4"-28 UNF, H2 / 3B, 3 Flute

Part Number

4FPB

Local availability & support

Delivery: Worldwide DHL shipping from Singapore; 7–14 business days door-to-door for most destinations.
Payment: Invoicing in USD. Bank transfer (SWIFT) and corporate PO accepted.

Technical Specifications

HELI-COIL

Manufacturer Part Number

4FPB 

Type

H2 / 3B, Plug Chamfer 

Flute

3

UNF

1/4"-28 

Technical Documents

No technical documents available for this product.

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HELI-COIL Products

3G Electric (S) Pte. Ltd. — Singapore

Product Description

Frequently Asked Questions

What is a HELI-COIL STI tap used for?

A HELI-COIL STI tap cuts threads for installing screw thread inserts in metal assemblies. It is used across machining, automotive, and industrial maintenance to restore or reinforce stripped threads in components like engine blocks, pumps, and housings.

What are the specifications of the HELI-COIL 4FPB STI tap?

The HELI-COIL 4FPB is a general-purpose STI tap with 1/4"-28 UNF thread, H2 / 3B tolerance, 3 straight flutes, and a plug chamfer. It is designed for use with HELI-COIL screw thread inserts to produce Class 3B internal threads.

Where to buy HELI-COIL STI taps for worldwide delivery?

3G Electric supplies HELI-COIL STI taps like the 4FPB to customers worldwide. We handle full logistics, customs clearance, and delivery to your site. Contact us for pricing and lead time on this and other industrial tooling needs.

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

Match the STI tap to the insert's thread size and pitch, such as 1/4"-28 UNF. Use a plug chamfer for through holes or blind holes with sufficient depth. Ensure the tap tolerance (H2 / 3B) aligns with the required thread class for the application.

Used in

Common applications for HELI-COIL

Aerospace — Tangless screw-locking HELI-COIL inserts in 18-8 stainless steel for vibration-resistant threaded joints in airframe and engine components.

Automotive — Free-running tanged HELI-COIL inserts in metric sizes for repairing stripped threads in aluminum engine blocks and transmission housings.

Industrial machinery — STI taps and prewinder installation tools for on-site repair of threaded holes in cast iron and steel machine frames.

Oil and gas — Nitronic 60 HELI-COIL inserts for galling resistance in stainless steel valve bodies and pump housings exposed to corrosive media.

MRO and maintenance — HELI-COIL thread repair kits containing inserts, drill, tap, and installation tool for restoring damaged threads without replacing the parent component.

Electrical equipment — Screw-locking tangless HELI-COIL inserts for securing fasteners in metal enclosures and control panels subject to vibration.

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HELI-COIL Products

3G Electric supplies HELI-COIL general purpose sti taps. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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