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HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 1/4"-28 Thread Size - Screw-Locking Tanged Helical Inserts
HELI-COILScrew-Locking Tanged Helical Inserts

HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 1/4"-28 Thread Size

HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 1/4"-28 Thread Size, 500 PK (MPN 3591-4CNW500S). This 18-8 stainless steel insert features a Dry Film Lubricant finish, right-hand fine threads, and a…

SKU 3G-OTH-528862

Brand
HELI-COIL
Item
Helical Insert: Tanged Tang Style, Screw-Locking, 1/4"-28 Thread Size
Category
Screw-Locking Tanged Helical Inserts
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Technical Specifications

HELI-COIL
Manufacturer Part Number
3591-4CNW500S
Type
Screw-Locking, 500 PK
Tensile Strength
200,000 to 250,000 psi
Finish Type
Dry Film Lubricant
Thread Size
1/4"-28
Thread Type
Fine
STI Tap Size
1/4"-28
Thread Direction
Right Hand
Compatible Material
Metal
Material Grade/Class
18-8
System of Measurement
Inch
View Full Spec Sheet

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HELI-COIL Products
3G Electric (S) Pte. Ltd. — Singapore

Product Description

HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 1/4"-28 Thread Size, 500 PK (MPN 3591-4CNW500S). This 18-8 stainless steel insert features a Dry Film Lubricant finish, right-hand fine threads, and a tensile strength of 200,000 to 250,000 psi. Designed for metal substrates, it requires an STI Tap Size of 1/4"-28 and is supplied in inch-system packaging.

Frequently Asked Questions

What is a HELI-COIL screw-locking helical insert used for?

A HELI-COIL screw-locking helical insert repairs or reinforces threads in metal substrates, providing a strong, wear-resistant thread that resists loosening under vibration. It is commonly used in automotive, aerospace, and industrial maintenance applications where thread integrity is critical.

What are the specifications of the HELI-COIL 3591-4CNW500S insert?

This HELI-COIL insert has a 1/4"-28 fine thread size, right-hand direction, and is made from 18-8 stainless steel with a Dry Film Lubricant finish. It offers a tensile strength of 200,000 to 250,000 psi and requires an STI Tap Size of 1/4"-28. Supplied in a 500-piece pack.

Where to buy HELI-COIL helical inserts in worldwide?

3G Electric supplies HELI-COIL helical inserts worldwide, handling full logistics and customs clearance for international orders. As a global industrial solutions provider, we source and deliver genuine HELI-COIL parts like the 3591-4CNW500S to any location, ensuring compliance with local import requirements.

How to install a HELI-COIL tanged screw-locking insert?

To install a HELI-COIL tanged insert, drill out the damaged thread to the specified size, tap the hole using the correct STI tap (1/4"-28 for this insert), then wind the insert into the tapped hole using a HELI-COIL installation tool. Break off the tang after installation for a permanent, locking thread.

Used in

Common applications for HELI-COIL
Aerospace engine repair — HELI-COIL STI taps for M12x1.75 metric threads in aluminum alloy components
Automotive transmission rebuild — HELI-COIL STI taps for 7/16-14 UNC threads in cast iron housings
Industrial pump maintenance — HELI-COIL STI taps for #10-32 UNF threads in stainless steel pump bodies
Hydraulic cylinder repair — HELI-COIL STI taps for M6x1 metric threads in steel cylinder heads
General manufacturing — HELI-COIL STI taps for 9/16-18 UNF threads in machinery base plates

HELI-COIL Products

3G Electric supplies HELI-COIL screw-locking tanged helical inserts. We supply genuine products with in-stock availability on common SKUs, technical documentation, commissioning support, and warranty service — worldwide.

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HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, #10-32 Thread Size, Plain, Plain, 100 PK (MPN A3591-3EN285). Key specifications — Material Grade/Class: Nitronic 60; Thread Direction: Right Hand; STI Tap Size: #10-32; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 psi; Thread Type: Fine.
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HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, M6-1.00 Thread Size, Plain, 100 PK (MPN A4184-6EN120). Key specifications — Material Grade/Class: Nitronic 60; Thread Direction: Right Hand; STI Tap Size: M6-1.00; Compatible Material: Metal; System of Measurement: Metric; Brand: HELI-COIL; Drill Bit Size: 6.25mm; Tensile Strength: 200,000 psi.
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HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, M6-1.00 Thread Size, Plain, 100 PK (MPN A4184-6EN120). Key specifications — Material Grade/Class: Nitronic 60; Thread Direction: Right Hand; STI Tap Size: M6-1.00; Compatible Material: Metal; System of Measurement: Metric; Brand: HELI-COIL; Drill Bit Size: 6.25mm; Tensile Strength: 200,000 psi.
HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 1 1/4"-12 Thread Size, Plain, 100 PK (MPN A3591-20CN1250). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: 1-1/4"-12; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Fine.
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HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 1 1/4"-12 Thread Size, Plain, 100 PK (MPN A3591-20CN1250). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: 1-1/4"-12; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Fine.
HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, M4-0.70 Thread Size, 100 PK (MPN A4184-4CNW060). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: M4-0.70; Compatible Material: Metal; System of Measurement: Metric; Brand: HELI-COIL; Drill Bit Size: 4.2mm; Tensile Strength: 200,000 to 250,000 psi.
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HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 5/16"-18 Thread Size, Plain, 100 PK (MPN A3585-5CN469). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: 5/16"-18; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Coarse.
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HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 5/16"-18 Thread Size, Plain, 100 PK (MPN A3585-5CN469). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: 5/16"-18; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Coarse.
HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 1/4"-28 Thread Size, 100 PK (MPN A3591-4CNW500). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: 1/4"-28; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Fine.
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HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, 1/4"-28 Thread Size, 100 PK (MPN A3591-4CNW500). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: 1/4"-28; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Fine.
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HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, #10-32 Thread Size, Plain, Plain, 100 PK (MPN A3591-3CN190). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #10-32; Compatible Material: Metal; System of Measurement: Inch; Brand: HELI-COIL; Tensile Strength: 200,000 to 250,000 psi; Thread Type: Fine.