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

The HELI-COIL Helical Insert is a tanged tang style, screw-locking insert in a plain finish, supplied in a 100-piece pack. This inch-system insert features a 1/4"-28 fine thread, a tensile strength of 200,000 psi…

SKU 3G-OTH-528918

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

HELI-COIL
Manufacturer Part Number
A3591-4EN500
Type
Screw-Locking, Plain, 100 PK
Tensile Strength
200,000 psi
Finish Type
Plain
Thread Size
1/4"-28
Thread Type
Fine
STI Tap Size
1/4"-28
Thread Direction
Right Hand
Compatible Material
Metal
Material Grade/Class
Nitronic 60
System of Measurement
Inch
View Full Spec Sheet

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

Product Description

The HELI-COIL Helical Insert is a tanged tang style, screw-locking insert in a plain finish, supplied in a 100-piece pack. This inch-system insert features a 1/4"-28 fine thread, a tensile strength of 200,000 psi, and is made from Nitronic 60 material for use in metal. It requires an STI tap size of 1/4"-28 and has a right-hand thread direction.

Frequently Asked Questions

What is a HELI-COIL helical insert used for?

A HELI-COIL helical insert repairs or reinforces threads in metal components. This screw-locking, tanged tang style insert with 1/4"-28 fine threads provides strong, wear-resistant threads in applications like automotive, aerospace, and industrial machinery, preventing thread stripping and extending part life.

What are the specifications of the HELI-COIL A3591-4EN500 insert?

This HELI-COIL insert has a 1/4"-28 fine thread size, right-hand direction, and requires an STI tap size of 1/4"-28. It is made from Nitronic 60 material with a tensile strength of 200,000 psi, comes in a plain finish, and is supplied in a 100-piece pack.

Where to buy HELI-COIL helical inserts worldwide?

3G Electric supplies HELI-COIL helical inserts worldwide. As a global industrial solutions provider, we handle full logistics, customs clearance, and delivery to your location. Contact us to order the A3591-4EN500 screw-locking insert or other HELI-COIL thread repair products for your application.

How to install a HELI-COIL tanged helical insert?

To install a HELI-COIL tanged insert, drill the hole to the specified size, tap it using the correct STI tap (1/4"-28 for this insert), then use a tang-style installation tool to wind the insert into the tapped hole. After installation, break off the tang with a punch for a secure, screw-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, #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.
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, 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.
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.
HELI-COIL Helical Insert: Tanged Tang Style, Screw-Locking, M4-0.70 Thread Size, Plain, 1,000 PK (MPN 4184-4CN040S). 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, M4-0.70 Thread Size, Plain, 1,000 PK (MPN 4184-4CN040S). 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.
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.
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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.