Minerallac 5/16" Split Lock Wa...
IN STOCK (leaves warehouse same day if ordered before 3pm ET)
$50.09
$11.43
Minerallac 5/16" Split Lock Washers - Medium Split, Zinc Plated Steel, Hardened Bearing Surface, 100 Pack

Minerallac 5/16" Split Lock Washers - Medium Split, Zinc Plated Steel, Hardened Bearing Surface, 100 Pack

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Model: 40530J

In Stock (leaves warehouse same day if ordered before 3pm ET)

$50.09
$11.43
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Minerallac 5/16" Split Lock Washers - Medium Split, Zinc Plated Steel, Hardened Bearing Surface

Professional Fastening Solution for Vibration Resistance & Load Distribution

Minerallac 5/16" Split Lock Washers deliver professional-grade fastening performance with zinc plated steel construction and hardened bearing surfaces. These medium split lock washers provide superior torque control and load distribution while resisting loosening caused by vibration and corrosion, making them essential components for reliable mechanical connections.

Professional Features & Benefits

  • 5/16" Size with Precision Dimensions: 0.322" inside diameter and 0.583" outside diameter ensure proper fit and optimal performance in standard fastening applications.
  • Zinc Plated Steel Construction: Provides excellent corrosion resistance and durability while maintaining the strength characteristics needed for demanding applications.
  • Hardened Bearing Surface: Creates more uniform torque control and superior load distribution compared to standard washers, enhancing connection reliability.
  • Medium Split Design: Optimized split configuration applies greater bolt tension per unit of applied torque for enhanced clamping force.
  • Rockwell Hardness C38-43: Professional hardness rating ensures consistent performance and resistance to deformation under load.
  • 0.078" Thickness: Engineered thickness provides optimal spring action and vibration resistance without excessive bulk.
  • Vibration & Corrosion Resistance: Advanced design characteristics resist loosening caused by both mechanical vibration and environmental corrosion.

Technical Specifications

  • Country Of Origin: China
  • Inside Diameter: 0.322
  • Outside Diameter: 0.583
  • Product Color: Silver
  • Product Finish: Zinc Plated
  • Product Material: Steel
  • Product Type: Split Lock Washer
  • Rockwell Hardness: C38 - 43
  • Thickness: 0.078

Professional Applications

  • Industrial Equipment Assembly
  • Commercial Construction Projects
  • Electrical Panel & Enclosure Installation
  • HVAC System Components
  • Machinery & Equipment Maintenance
  • Professional Repair & Service Operations
  • Critical Infrastructure Applications

Why Choose Minerallac Quality?

Minerallac split lock washers combine precision engineering with zinc plated steel construction and professional hardness ratings to deliver reliable fastening performance. The hardened bearing surface and corrosion-resistant finish ensure long-term durability in demanding professional applications where vibration resistance and load distribution are critical.

Manufacturer Resources

Product Specs

Inside Diameter:
0.322
Outside Diameter:
0.583
Product Color:
Silver
Product Finish:
Zinc Plated
Product Material:
Steel
Product Type:
Washer
Rockwell Hardness:
C38 - 43
Thickness:
0.078
Department:
Electrical
Product Subgroup:
Electrical Fasteners
Product Group:
Hangers, Supports & Fasteners

Minerallac 40530J – Frequently Asked Questions

1) Will a Minerallac 40530J lock washer fit a 5/16 inch bolt or threaded rod?
Yes. The 40530J split lock washer has a 0.322 inch inside diameter, which clears a 5/16 inch (0.3125 inch) bolt shank or 5/16-18 threaded rod with minimal slop. Outside diameter is 0.583 inch, so it sits under a standard 5/16 hex nut or bolt head without overhanging the bearing area.
2) Should I use a split lock washer or a flat washer under my nut?
They do different jobs. A flat washer spreads load over soft or oversized-hole material; the Minerallac 5/16 split lock washer is a spring element that keeps bolt tension when vibration would otherwise back the nut off. On vibrating equipment, HVAC units, and machinery mounts you often want both: flat washer against the material, split lock washer against the nut. The split design applies greater bolt tension per unit of applied torque, and its hardened bearing surface gives more uniform torque control than a plain washer.
3) Is zinc plated steel good enough for these washers outdoors or in a damp mechanical room?
Zinc plated steel handles indoor and sheltered damp conditions, which covers most panel, enclosure, and mechanical room work. It is a sacrificial coating, not stainless, so in direct weather exposure, coastal air, or wash-down areas expect eventual red rust at cut edges and the split. For those openings specify a stainless or hot-dip galvanized washer instead.
4) How do I order 5/16 Minerallac lock washers, and what comes in the package?
Order by part number 40530J. That is the 5/16 inch medium split, zinc plated steel lock washer supplied in a 100 piece jar, which is the usual way an electrician or maintenance shop buys them for the truck or the crib.
5) Are these washers hard enough not to flatten out and lose their spring?
They are heat treated to Rockwell C38-43, which is the hardness range a split lock washer needs to bite into the nut face and spring back rather than crush permanently under clamp load. That hardness, plus the hardened bearing surface, is what keeps torque consistent on repeated service work where fasteners get broken loose and retightened.
6) Can I use these 5/16 lock washers on strut and electrical enclosure hardware?
That is the intended use. The 40530J is an electrical fastener, and typical applications include electrical panel and enclosure installation, HVAC components, industrial equipment assembly, and machinery maintenance. Any 5/16 bolt, strut nut, or threaded rod connection that sees vibration is a fit; just confirm your hole and nut suit the 0.583 inch outside diameter.
7) Where are Minerallac 40530J lock washers made?
The 40530J 5/16 split lock washer is manufactured in China. That matters on public work where a domestic-origin requirement is written into the spec, so check the project documents before submitting these on a government or federally funded job.
How fast can I get the Minerallac 40530J delivered?
Most orders ship the same day from our distribution partners, with quick delivery throughout the continental U.S. Need it urgently? Contact Us for expedited shipping options.
Can I return it if it doesn’t work for me?
Yes—ZenSupply offers a hassle-free return policy. If the product isn’t the right fit, reach out to our support team for a return authorization or setup a return by following our return instructions.
Does the Minerallac 40530J come with a warranty?
Absolutely. The Minerallac 40530J is backed by a manufacturer’s warranty. For full warranty terms, check the product documentation or Contact Us.
How do I get technical support or installation help for the Minerallac 40530J?
You can call, text, or email our expert support team for fast answers. We’re here to help with product selection, installation tips, and troubleshooting. Contact Us
Why buy the Minerallac 40530J from ZenSupply?
ZenSupply makes it easy to get the commercial door hardware you need—fast shipping, expert support, and rewards on every order. Our team is always ready to help you choose the right product for your project.
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