Midland Black Malleable Iron Locknut
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Regular price
$1.66
- ✔ In Stock — Ships Same Day or Next Business Day
- ✔ Trusted by contractors and industrial buyers
- ✔ Bulk pricing available — Request a Quote
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Contact us for contractor pricing or large quantity discounts →
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✔ In Stock – Fast Shipping from Multiple U.S. Warehouses
✔ Contractor-Grade Black Malleable Iron – Threaded NPT
✔ Bulk Pricing Available – Multiple Sizes In Stock
✔ Contractor-Grade Black Malleable Iron – Threaded NPT
✔ Bulk Pricing Available – Multiple Sizes In Stock
High Demand Item – Frequently Reordered by Plumbing and Gas Contractors
The Midland Black Malleable Iron Locknut is a threaded nut used to lock and secure fittings, flanges, and pipe connections in black iron piping systems. Available in multiple sizes — select from the dropdown above.
Black malleable iron construction with NPT threads. Used to secure and lock threaded connections in place. Conforms to ASTM A197.
Applications
- Securing threaded fittings and flanges in gas piping
- Locking pipe connections in compressed air systems
- General plumbing and mechanical piping applications
- Industrial piping installations
IMPORTANT:
- For low-pressure applications only — not rated for high-pressure service
- Black iron finish — not suitable for outdoor or corrosive environments without additional protection
- Always verify local code compliance before installation
Key Features
- Black malleable iron — ASTM A197
- NPT threads
- Secures and locks threaded connections
- Multiple sizes available
Frequently Asked Questions
What is a locknut used for?
Threaded onto a fitting or pipe to lock and secure the connection — prevents loosening.
What thread type?
NPT threads.
Are these galvanized?
No — black iron finish.
What standards?
ASTM A197.
Why Contractors Choose This Product
- Locks threaded connections securely
- NPT compatibility with standard fittings
- Stocked in 1/2" through 2"
- ASTM A197 conforming
✔ In Stock – Ready to Ship
✔ Bulk Pricing Available
✔ Fast Shipping from Multiple U.S. Warehouses
✔ Built for Contractors, Not DIY
✔ Bulk Pricing Available
✔ Fast Shipping from Multiple U.S. Warehouses
✔ Built for Contractors, Not DIY