Palnut Type Lock Nut | Mechanically Galvanized | Poleline Hardware

Reliable Spring-Tension Locking for Poleline Hardware. The Yokelink Palnut Type Locknut is an engineered, lightweight secondary fastener designed to prevent the primary load-bearing nuts from loosening due to high vibration, wind loads, or hardware shrinkage on utility poles.

How the Spring Action Works: Stamped from high-quality AISI 1050 Spring Steel, the Palnut is installed on top of a standard square or hex nut. When tightened with a wrench, the Palnut distorts slightly, creating a powerful, spring-like prevailing torque that grips the bolt threads and firmly presses against the primary nut. When the load is released, it returns to its original shape.

To maintain the integrity of the spring steel and ensure precise thread engagement, our Palnut type locknuts are Mechanically Galvanized to ASTM B695 Class 50, providing excellent corrosion resistance without the hydrogen embrittlement risks associated with standard hot-dip galvanizing.

DIN 7967 metric Hex Self-locking counter Pal Nut and stainless steel Palnut are available in Yokelink per the request.

 

Key Features of Pal Nut

Material: Premium AISI 1050 Spring Steel.

Mechanism: Spring-tension distortion creates a secure, vibration-proof lock.

Profile: Low-profile, lightweight stamped hex design.

Coating: Mechanically Galvanized (ASTM B695) for outdoor durability.

Production Process of Pal Nut Type Locknut

 

Pal nuts are manufactured from Spring steel. After blanking and stamping to form the thin, curved locking profile, the blanks are punched and tapped to create precise internal threads. Deburring and surface finishing ensure smooth assembly. The nuts are then hot-dip galvanized in accordance with ASTM A153 for corrosion resistance. All production and inspection comply with IEEE C135.1 and IEEE C135.80 standards for overhead power line applications.

 

Yokelink Quality Control and Testing Equipments

 

We don't just reference standards; we also verify them in practice: each batch of products undergoes destructive tensile testing in our internal laboratory to ensure load performance exceeds the minimum requirements of IEEE C135.1 / IEEE C138.80 or CSA specification; we use optical comparators to ensure the geometric accuracy of chamfered tips and rolled threads, enabling convenient on-site installation; at the same time, we conduct comprehensive testing on Rockwell hardness, coating thickness, and other parameters, and each shipment is accompanied by the original manufacturer's material specifications (MTRs) and quality inspection reports, with all data traceable back to the raw material furnace number.

The Application of Pal Nut Type Locknut

 

Pal nut type locknuts are widely used in overhead transmission and distribution lines, pole fixtures, cross arms and various fastener assemblies. As secondary locking fasteners, they effectively prevent loosening caused by vibration and outdoor working conditions. Made from AISI 1050 carbon steel and hot-dip galvanized per ASTM A153, they feature good corrosion resistance. Fully compliant with IEEE C135.1 and IEEE C135.80 standards, they provide safe, reliable and stable locking for long-term power line operation.

 

 

Yokelink Product Quality Inspection Report

 

We provide comprehensive inspection services for machine bolts, including SGS test bolts and formal Production Part Inspect Report (PPIR). The SGS tests verify the bolts’ compliance with international standards like ASTM A307 and IEEE C135.80, covering mechanical properties and corrosion resistance. The PPIR details all inspection items, ensuring each machine bolt meets dimensional, performance and quality requirements, providing reliable quality assurance for overhead line and industrial applications.

 

Technical Specifications of Pal Nut type Locknut

 

 

Part No.	Size	Width	Height	Weight
		Inch (B)	Inch (A)	Kg / Pcs
PN-38	3/8"-16	9/16	0.145	0.001
PN-12	1/2"-13	13/16	0.190	0.003
PN-58	5/8"-11	15/16	0.213	0.005
PN-34	3/4"-10	1-1/8	0.246	0.006
PN-78	7/8"-9	1-5/16	0.311	0.010
PN-100	1"- 8	1-5/8	0.336	0.021

 

 

DIN 7967 metric Hex Self-locking counter Pal Nut and stainless steel Palnut are available per the request.

 

Cross Reference (Industry Equivalents):

 

Size	Part No.	HUBBELL	ALLIED BOLT
3/8"-16	PN-38	3530	7851
1/2"-13	PN-12	3531	7852
5/8"-11	PN-58	3532	7853
3/4"-10	PN-34	3533	7854
7/8"-9	PN-78	3534	7855
1"- 8	PN-100	3515

 

(Note: Manufacturer part numbers are for reference only. Yokelink products are interchangeable based on IEEE standards.)

 

Frequently Asked Questions (FAQ)

 

Q1: What is the difference between an MF Locknut and a Palnut?

A: While both are secondary locknuts used in poleline construction, they operate differently. An MF Locknut is a solid, concave-shaped nut that flattens when tightened to lock the threads. A Palnut is a lightweight, hex-shaped nut stamped from spring steel. It uses spring tension—distorting under load and gripping the threads—to prevent the primary nut from vibrating loose.

Q2: Why are Palnut type locknuts usually mechanically galvanized instead of hot-dip galvanized?

A: Palnuts are made of high-carbon spring steel (like AISI 1050) and have extremely thin, fine profiles. Traditional Hot-Dip Galvanizing (HDG) involves extreme heat that can ruin the spring temper of the steel and clog the thin threads with zinc. Mechanical galvanizing (ASTM B695) applies a protective zinc layer at room temperature, preserving the spring action and eliminating the risk of hydrogen embrittlement.

Q3: How do you install a Palnut on a utility pole?

A: First, securely tighten the primary load-bearing nut (such as a square or heavy hex nut) against the hardware. Then, thread the Palnut onto the bolt with the smooth face towards the primary nut. Spin it down finger-tight, and then use a wrench to tighten it an additional 1/3 to 1/2 turn to engage the spring locking action.

Value-Added Supply Chain Services

 

1. Blanket Order & Free Warehousing

Yokelink offers Blanket Order programs: Place an annual order to lock prices, we manufacture your total volume and hold stock in our facility free of charge. Split Shipments: Schedule partial shipments (e.g., monthly or quarterly) based on your project progress. You get the benefits of just-in-time delivery without the risk of shortages.

2. DDP Shipping (USA Duties Included)Landed Cost Certainty

We handle the complex logistics. Our DDP (Delivered Duty Paid) service covers sea freight, US Customs clearance, and Section 301 tariffs. The price we quote is the final price delivered to your door / Warehouse.

3. Free Sample Program

We offer Free Samples to qualified commercial buyers for testing and approval.

 

Reference Information:

 

For IEEE C135.1 technical details behind our specification, see Understanding IEEE C135.1 Standard

https://www.yokelink.com/blog/understanding-ieee-c135-1-standard-for-zinc-coated-steel-bolts-and-nuts-in-overhead-line-construction-32333.html

 

IEEE C135.1 vs. IEEE C135.80: Key Differences in Pole Line Fasteners

https://www.yokelink.com/news/ieee-c135-1-vs-ieee-c135-80-key-differences-in-pole-line-fasteners-353686.html

 

IEEE C135.1 Specification Download:

 

https://www.yokelink.com/news/ansi-c135-1-ieee-std-c135-1-specification-163053.html

 

How to Choose the Right Machine Bolt Under IEEE C135.1

https://www.yokelink.com/news/how-to-choose-the-right-machine-bolt-under-ieee-c135-1-353752.html