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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

The HELI-COIL Helical Insert is a tanged tang style, screw-locking insert in a 100-pack, featuring a 1/4"-28 fine thread, right-hand direction, and 18-8 material grade. It offers a tensile strength of 200,000 to…

SKU 3G-OTH-529108

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
A3591-4CNW187
Type
Screw-Locking, 100 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

The HELI-COIL Helical Insert is a tanged tang style, screw-locking insert in a 100-pack, featuring a 1/4"-28 fine thread, right-hand direction, and 18-8 material grade. It offers a tensile strength of 200,000 to 250,000 psi, with a dry film lubricant finish, and is compatible with metal substrates.

Frequently Asked Questions

What is a HELI-COIL helical insert used for?

A HELI-COIL helical insert repairs or reinforces threads in metal substrates. This screw-locking, tanged tang style insert with 1/4"-28 fine threads provides strong, wear-resistant threads in aluminum, cast iron, or steel components, preventing thread stripping under high-stress applications.

What are the specifications of the HELI-COIL A3591-4CNW187 insert?

This HELI-COIL insert has a 1/4"-28 fine thread, right-hand direction, and 18-8 material grade. It offers a tensile strength of 200,000 to 250,000 psi, a dry film lubricant finish, and is compatible with metal substrates. The STI tap size is 1/4"-28, and it comes in a 100-pack.

Where to buy HELI-COIL helical inserts in worldwide?

3G Electric supplies HELI-COIL helical inserts worldwide. As a global industrial solutions provider, we handle full logistics and customs clearance to deliver these screw-locking inserts to your facility. Contact us for availability and lead time on the A3591-4CNW187 100-pack.

How to install a HELI-COIL tanged tang insert?

To install a HELI-COIL tanged tang insert, drill to the specified STI tap size (1/4"-28), tap the hole with the corresponding STI tap, then use a tang break-off tool to install the insert. After installation, break off the tang with a punch. Always follow the manufacturer's instructions for best results.

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, M6-1.00 Thread Size, 1,000 PK (MPN 4184-6CNW090S). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: M6-1.00; Compatible Material: Metal; System of Measurement: Metric; 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, 7/8"-9 Thread Size, 1 5/16 in Overall Lg (MPN 3585-14CN1312). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: 7/8"-9; 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, 7/8"-9 Thread Size, 1 5/16 in Overall Lg (MPN 3585-14CN1312). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: 7/8"-9; 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, #6-32 Thread Size, Plain, Plain, 100 PK (MPN A3585-06CN276). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #6-32; 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, #6-32 Thread Size, Plain, Plain, 100 PK (MPN A3585-06CN276). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #6-32; 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, Plain, 1,000 PK (MPN 3591-4CN250S). 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, Plain, 1,000 PK (MPN 3591-4CN250S). 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, M6-1.00 Thread Size, Plain, 100 PK (MPN A4184-6EN060). 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 A4184-6EN060). 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, M4-0.70 Thread Size, Plain, 100 PK (MPN A4184-4CN060). 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, 100 PK (MPN A4184-4CN060). 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, #8-32 Thread Size, Plain, 1,000 PK (MPN 3585-2CN164S). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #8-32; 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, #8-32 Thread Size, Plain, 1,000 PK (MPN 3585-2CN164S). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: #8-32; 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, M2.5-0.45 Thread Size, Plain, 1,000 PK (MPN 4184-2.5CN025S). Key specifications — Material Grade/Class: 18-8; Thread Direction: Right Hand; STI Tap Size: M3-0.50; Compatible Material: Metal; System of Measurement: Metric; Brand: HELI-COIL; Drill Bit Size: 2.55mm; Tensile Strength: 200,000 to 250,000 psi.