What Thread-Locking Solution Are You Looking For?
Carbon steel key-locking thread inserts are manufactured from C1215 carbon steel and treated with a phosphate coating for corrosion protection. Each insert features 2 to 4 pre-assembled locking keys, evenly spaced around the external thread.
For internal thread sizes M8 and above (or 5/16-18 and above), the insert is equipped with four locking keys; smaller sizes are supplied with two locking keys.
After the insert is installed into a tapped hole, the locking keys are driven down into the parent material, creating a strong mechanical locking effect. These inserts are widely used in applications with high requirements for thread strength, such as military equipment, aerospace, railway locomotives, and vibration-intensive machinery.
Key Features of Carbon Steel Key-Locking Inserts
- Particularly suitable for applications requiring high-strength internal threads, offering excellent resistance to vibration and pull-out forces
- Compared with conventional stainless steel wire thread inserts, carbon steel key-locking inserts provide significantly greater enhancement of thread strength
- Available in the same specification range as stainless steel versions, including both metric and imperial sizes
- Simple to use and easy to install
The primary functions of key-locking inserts are thread repair and thread reinforcement. As an effective thread repair solution, they allow damaged internal threads to be restored quickly and reliably. When installed in low-strength base materials, key-locking inserts can greatly improve the strength and service life of threaded holes.
Application Case
Thread Reinforcement for Wellhead Valve Flange Connections in Oil Drilling Equipment
Challenge
An oilfield equipment manufacturer encountered long-term issues with flange bolt connections in wellhead valve systems used in both onshore and offshore drilling operations. These connections were subjected to high-pressure pulsation, strong vibration, and frequent start-stop cycles.
Under high loads and repeated assembly and disassembly, directly tapped threads in steel valve bodies were prone to thread wear, loosening, and even failure, creating potential leakage and safety risks.
Solution
Carbon steel key-locking thread inserts (M12 size) were introduced into the valve flange connection points to reinforce critical threaded holes. The carbon steel material provides high strength and excellent fatigue resistance, while the driven locking keys form a secure mechanical lock, ensuring stable preload even under high pressure and vibration.
Installation Process
1.Drill and tap the flange connection holes to the required size
2.Thread the carbon steel key-locking insert into the prepared hole
3.Drive the locking keys into the valve body material to prevent rotation or pull-out
4.Assemble the flange and valve components using high-strength bolts
Results
✔ No loosening or leakage under high-pressure conditions, verified through multiple pressure cycle tests
✔ Significantly improved thread load-bearing capacity, allowing higher axial loads and tightening torque
✔ Suitable for repeated assembly and disassembly, extending thread service life in wellhead equipment
✔ Enhanced overall system safety by reducing the risk of connection failure
Inch Series Light-Duty Carbon Steel Key-Locking Insert Specifications
|
Part No. |
Thread Insert Size |
Installation Parameters |
Disassembly Parameters |
|||||||
|
Internal Thread (2B) |
External Thread (2A) |
Length |
Length |
Bottom Hole Size |
Countersink Size |
Tapping Drill |
Drill Bit |
|||
|
Tap Size |
Depth |
Dimension |
Depth |
|||||||
|
RKKA 10-24 |
10-24 |
5/16-18 |
0.312 |
0.22 |
0.272 |
0.323 |
5/16-18 |
0.37 |
7/32 |
5/32 |
|
RKKA 10-32 |
10-32 |
5/16-18 |
0.312 |
0.22 |
0.272 |
0.323 |
5/16-18 |
0.37 |
7/32 |
5/32 |
|
RKKA 1/4-20 |
1/4-20 |
3/8-16 |
0.375 |
0.22 |
0.332 |
0.385 |
3/8-16 |
0.43 |
9/32 |
3/16 |
|
RKKA 1/4-28 |
1/4-28 |
3/8-16 |
0.375 |
0.22 |
0.332 |
0.385 |
3/8-16 |
0.43 |
9/32 |
3/16 |
|
RKKA 5/16-18 |
5/16-18 |
7/16-14 |
0.437 |
0.22 |
0.397 |
0.447 |
7/16-14 |
0.50 |
11/32 |
3/16 |
|
RKKA 5/16-24 |
5/16-24 |
7/16-14 |
0.437 |
0.22 |
0.397 |
0.447 |
7/16-14 |
0.50 |
11/32 |
3/16 |
|
RKKA 3/8-16 |
3/8-16 |
1/2-13 |
0.500 |
0.24 |
0.453 |
0.510 |
1/2-13 |
0.56 |
13/32 |
3/16 |
|
RKKA 3/8-24 |
3/8-24 |
1/2-13 |
0.500 |
0.24 |
0.453 |
0.510 |
1/2-13 |
0.56 |
12/32 |
3/16 |
|
RKKA 7/16-14 |
7/16-14 |
9/16-12 |
0.562 |
0.27 |
0.516 |
0.572 |
9/16-12 |
0.62 |
15/32 |
3/16 |
|
RKKA 7/16-20 |
7/16-20 |
9/16-12 |
0.562 |
0.27 |
0.516 |
0.572 |
9/16-12 |
0.62 |
15/32 |
3/16 |
|
RKKA 1/2-13 |
1/2-13 |
5/8-11 |
0.625 |
0.28 |
0.578 |
0.635 |
5/8-11 |
0.68 |
17/32 |
3/16 |
|
RKKA 1/2-20 |
1/2-20 |
5/8-11 |
0.625 |
0.28 |
0.578 |
0.635 |
5/8-11 |
0.68 |
17/32 |
3/16 |
Installation Instructions for Keensert-Type Inserts
Step 1
Drill the hole using a standard drill bit or remove the existing damaged thread.
Add a countersink if required.
Refer to the specific Keensert product data for the correct hole size and dimensions.
Step 2
Tap the hole using a standard tap corresponding to the insert's external thread size.
Step 3
Thread the Keensert insert into the newly tapped hole.
Manual installation is possible, but the use of a dedicated installation tool ensures proper seating.
Step 4
Use the installation tool to drive the locking keys into the parent material.
● For insert-type products, use the back side of the tool
● For stud-type products, use the lower edge of the tool
FAQ
Q1: How do you ensure the quality of industrial components?
We have over 20 years of manufacturing experience in the thread insert industry and operate a comprehensive quality management system. The production process includes multiple inspection stages, such as IQC (Incoming Quality Control), IPQC (In-Process Quality Control), FQC (Final Quality Control), and OQC (Outgoing Quality Control), ensuring strict control at every stage of production.
Q2: What is your minimum order quantity (MOQ)?
The standard MOQ is 100 pieces.
For stocked standard models, quantities can be adjusted based on actual requirements.
Q3: What shipping methods and delivery times do you offer?
Small-batch orders are typically shipped via DHL, TNT, UPS, or FedEx.
Transit time depends on the destination.
Q4: Which Incoterms do you support?
EXW, FOB, CIF, and DDP.
Q5: What is your lead time?
For standard products, samples are usually shipped within 3 days, and bulk orders are completed within 5–7 working days.
Lead time for non-standard products depends on design complexity and machining processes.
Hot Tags: carbon steel key locking insert, China carbon steel key locking insert manufacturers, suppliers, factory, Key Locking Thread Repair Inserts, Keylocking Thread Repair Insert, Carbon Steel Key Locking Insert, Metric Key Locking Inserts, key locking inserts, Key Lock Threaded Inserts
