Form C washers have a slightly large overall diameter than Form A & B washers, as you can see by comparing the same sized washer in the table below. This means that they are particularly suitable for use with materials that are softer than hard metal (such as wood and plastic), as they give a wider spread of load and reduce the potential for damage. When it comes to flat washers, the good news is that regardless of where you buy them or who makes them, the dimensions should be almost exactly the same. This is because all metric flat washers are classed within certain Forms, and each form has the same dimensions regardless of manufacturer. Often called penny washers or mudguard washers, repair washers have an overall outside diameter that is larger than standard flat washers. Boltight Typhoon+ tensioners are our secure bolting solutions that have been developed to meet the technical and environmental demands of the wind energy market.

This increased surface area spreads the force (and hence the tension load) that is applied over a much greater area when the nut is tightened, making them ideal for use on weak or damaged surfaces. BS4320 washer forms A to D are typically supplied self-finish in a range of metals including steel alloys, brass and copper. Use the Expander System as a lug wear repair solution for an easy, cost effective and permanent repair method, provided to over 2 million customers globally. As with all of our fasteners, please note that it is the responsibility of the user to assess the suitability of the product in question. FORM A & B WASHERS

Explore reliable and resilient bolting solutions for common issues such as leakage, vibration, corrosion and thermal cycling in downstream oil & gas refineries.

Expander System is an award-winning patented solution with over one million systems installed since 1985. A permanent solution to lug bore wear that doesn’t require special skilled technician. The following table shows the exact dimensions of all our Form A & BWashers (don’t forget to make an allowance for the 1mm +/- tolerance in diameter as stated above).High performance and dedication to safety are in our DNA. The fact that we are the only company to offer CE marked securing washers is proof.