When a tap head is turned on or off, a rotating screw forces the tap washer to move up or down (respectively) within the body of the tap assembly. This lifts it away from the seat and opens up the flow valve. In doing so, it allows pressurised mains water held in the plumbing system to pass through the tap spout at varying volumes and speeds. Key to this function is the fact that tap washers are typically made from materials that can be squeezed or compressed to form a watertight seal (although exceptions do exist for certain tap types). This enables them to seal off the valve opening more effectively, even in cases where general usage-related wear and tear has caused small surface irregularities over time.

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 Rubber washers and gaskets are displaced and distorted more aggressively than some other materials under high compression forces. This can lead to increased signs of wear after extended use. They’re very low friction in operation, further contributing to both longevity and a smoother, easier tap action - hence being used more often on lever-style taps They achieve their purpose by creating an impenetrable physical barrier between the tap seat and the spout. The material construction of most tap washers also means that they’re able to fill and even out any irregularly-shaped voids between different parts of a tap fitting (generally the valve and the tap seat), effectively sealing off the tap spout from the valve. 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.What type of tap washer should I buy? The one aspect that tends to cause more confusion and uncertainty than any other regarding this question is often getting the correct sizing. Often called penny washers or mudguard washers, repair washers have an overall outside diameter that is larger than standard flat washers. Rubber tap washers are another popular choice for sealing many types of bath and sink taps. Sealing washers in rubber are sold at a wide variety of standard sizes - common requirements include the 15mm rubber washer, 1-inch rubber washer, 32mm rubber washer and 40mm rubber washer. BS4320 washer forms A to D are typically supplied self-finish in a range of metals including steel alloys, brass and copper.

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. Depending on the tap type and the specifics of its assembly, you may need large tap washers, mudguard washers, small tap washers, or even mini versions. Commonly used washer sizes for various indoor or outdoor taps include: 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. 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). When it comes to longevity and function in tap washers, rubber is considered to share many of the properties of nylon, although overall it is a much softer and more pliant material. This can mean that it creates a more effective seal against certain harder materials, or where there is more surface irregularity.Tap washers are designed to be used in nearly all types of taps, where their key role is to help control the flow of water. They can also work to prevent leaking and contamination while a tap is shut off. Regardless of the washer type and material, their basic function is to press down against the seat or flow valve on the inside of a tap assembly, creating a closed-off seal that stops water from flowing to the spout when the tap head is turned to the ‘off’ position. How Do Tap Washers Work? They also work differently to the other more traditional sealing washer types outlined above. In a tap that uses ceramic tap washers, a pair of close-fitting slotted ceramic discs replace the more standard nylon, rubber or fibre washer. One of the two ceramic discs is fixed in place, while the other can rotate through 90 degrees (hence quarter-turn).

Ceramic tap washers are hard-wearing and highly resistant to water erosion, meaning that they tend to last a long time