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HELI-COIL Screw-Locking Tanged Helical Insert, 1/4"-28, Plain, 100 PK - Screw-Locking Tanged Helical Inserts
HELI-COILScrew-Locking Tanged Helical Inserts

HELI-COIL Screw-Locking Tanged Helical Insert, 1/4"-28, Plain, 100 PK

The HELI-COIL Helical Insert is a tanged tang style, screw-locking insert with a 1/4"-28 fine thread, plain finish, and 18-8 material grade. It offers a tensile strength of 200,000 to 250,000 psi, is compatible with…

SKU 3G-OTH-529058

Also listed as: A35914CN250 · A3591 4CN250

Brand
HELI-COIL
Item
Screw-Locking Tanged Helical Insert, 1/4"-28, Plain, 100 PK
Category
Screw-Locking Tanged Helical Inserts
Available to Order
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Local availability & support — Singapore

Local office
20 Woodlands Link #09-05, Singapore 738733
Phone
+65 8878 8355
Delivery
Same-day or next-business-day delivery within Singapore for in-stock items; 7–14 days for factory-order parts from Europe.
Payment
Invoicing in SGD. PayNow, bank transfer, and corporate PO accepted.
Ships to
Singapore

Technical Specifications

HELI-COIL
Manufacturer Part Number
A3591-4CN250
Type
Screw-Locking, Plain, 100 PK
Tensile Strength
200,000 to 250,000 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
18-8
System of Measurement
Inch

Technical Documents

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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 with a 1/4"-28 fine thread, plain finish, and 18-8 material grade. It offers a tensile strength of 200,000 to 250,000 psi, is compatible with metal, and comes in a 100-piece pack (MPN A3591-4CN250).

Frequently Asked Questions

What is a HELI-COIL helical insert used for?

A HELI-COIL helical insert repairs or reinforces threaded holes in metal. The screw-locking design resists vibration loosening, making it ideal for automotive, aerospace, and industrial applications where joint integrity is critical.

What are the specifications of the HELI-COIL A3591-4CN250 insert?

This HELI-COIL insert has a 1/4"-28 fine thread, 18-8 material grade, and tensile strength of 200,000 to 250,000 psi. It is tanged tang style, screw-locking, plain finish, right-hand thread, and comes 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 and customs clearance to deliver genuine parts like the A3591-4CN250 to your facility, wherever it is located.

How to install a HELI-COIL tanged helical insert?

Install a HELI-COIL tanged insert by drilling to the specified STI tap size (1/4"-28), tapping the hole, then using a tang-style installation tool to wind the insert into place. After installation, break off the tang for a flush finish.

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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