Types of Wiper Blade Tests
One of the most common wiper blade tests is the initial wipe test, a reliable first assessment of the blade’s performance. A wiper blade is tested on a glass windshield for a desired make and model of vehicle and given a grade on a scale from one to ten. A wiper blade earns a grade of ten if there is no streaking, chatter lines, or remaining water on the wipe pattern. Lower grades are given when the blade leaves behind water, streaks, smears, or chatter lines. This test may be repeated for hundreds, thousands or even millions of cycles to predict the lifespan of the wiper blade and observe its performance over time.
The rubber compound used to make the wiper blade may undergo material testing, such as physical or environmental testing. Physical property testing for wiper blades assesses the mechanical strength of the rubber. This may include durability, hardness, tensile, elongation, and compression or permanent set testing. Environmental testing assesses how a wiper blade will perform in service by recreating variables of its anticipated service conditions in a controlled laboratory setting. Common examples include ozone, QUV, and Xenon arc weathering.
Custom testing protocols for wiper blades will vary based on the manufacturer’s goals. For example, a rubber testing laboratory may design a test to determine how long it takes for a wiper blade to clear away insect viscera or other debris that may collect on a windshield.
Testing may also be conducted on windshield and wiper blade coatings. For example, some manufacturers apply a coating to wiper blades to stiffen the edges for a more effective wipe. The performance of the coating, and its impact on coefficient of friction, can be tested in a laboratory.
Industry Standard Tests for Windshield Wiper Blades
There are several standard protocols for windshield wiper testing:
SAE J903—Passenger Car Windshield Wiper Systems
SAE J198—Windshield Wiper Systems - Trucks, Buses, and Multipurpose Vehicles
SAE J198 describes methods for evaluating the performance of wiper systems for two types of vehicles:
- Buses, trucks, and other multi-passenger vehicles with a gross vehicle weight rating (GVWR) over 10,000 pounds (4,500 kilograms).
- Light duty utility vehicles with a GVWR under 10,000 pounds (4,500 kilograms).
Other specifications designed to evaluate specific properties of rubber materials, such as ASTM D1149—Standard Test Methods for Rubber Deterioration—Cracking in an Ozone Controlled Environment, may also be referenced.
Rubber Endurance in the Automobile Industry
Everyday automobiles contain countless rubber components that must perform in virtually all types of weather and other challenging conditions. This is especially true for wiper blades, which are most often engaged in inclement weather conditions, such as rain, snow, and sleet. Plus, unlike hoses and other internal components, wiper blades receive virtually no protection from the elements and are constantly exposed to intense conditions, such as direct sun, that may accelerate aging.
Windshield wiper blade manufacturers face an additional challenge: Customers want their wiper blades to last as long as possible. Laboratory testing can help manufacturers determine which material, compound, and design choices will yield the most durable product and give them a competitive advantage.
When To Replace Wiper Blades
Most wiper blades are designed to last anywhere from six to twelve months in normal operating conditions. However, service life can vary. Signs that windshield wiper blades need to be replaced include:
- Visible streaks or bands of water left on the windshield immediately after the blade has been engaged.
- Cracks, tears, or missing chunks in the rubber.
- Bent or damaged frame components.
- Chatter, or high-frequency skipping across the windshield, rather than a smooth sweep.
Car owners may be able to extend the service life of their windshield wiper blades via preventive measures:
- Avoid using wipers on a dry windshield by maintaining adequate levels of wiper fluid.
- Avoid parking in the direct sun for prolonged periods as much as possible.
- Clear off snow and ice and allow icy windshields to thaw before engaging the wipers on winter days.
Windshield Wiper Inspections by ACE Laboratories
ACE Laboratories is proud to offer a full portfolio of windshield wiper blade testing services. Our state-of-the-art rubber testing laboratory is equipped for environmental conditioning, physical properties testing, lifespan testing, and custom protocols for wiper blades and wiper blade coatings. Our experts have years of experience testing rubber products designed for automotive applications, giving us specialized insight into the product development and testing process for wiper blades.
ACE has invested in direct video streaming for our wiper blade testing services, allowing for close, real-time supervision of initial wipe testing. Manufacturers have the option of watching every minute of the testing period themselves. This enables close collaboration between ACE experts and our customers when assigning subjective initial wipe grades to products under test.
Our custom setup for wiper blade inspection also allows us to monitor energy consumption during the testing process. With this capability, we can advise on highly specialized topics, such as the effect of different coatings on power consumption, wiper blade performance, and others.
To learn more about wiper blade testing services from ACE Laboratories, talk to a member of our team >
