Slide 1. Introduction.

            The class develops the different types of car chains, their advantages and disadvantages, and their implications for fleet management.

Slide 2. Types of car chains.

• Use of car chains.

            Due to climate change, winters seem to be getting colder and snowfall more intense every year, especially in mountainous areas or regions with extreme climates. That is why having snow chains in the trunk is a minimum requirement when adverse conditions are approaching and can make a significant difference in safety, as they provide greater traction and control of the vehicle.

              In cold areas, with temperatures not exceeding 7 degrees Celsius or where it snows frequently, it is best and safest to fit your vehicle with winter tires, also known by the acronym M+S, and even add chains pre-mounted on the rim if the snowfall is very heavy. As temperatures in Spain vary greatly depending on the province, it may be sufficient to drive with mixed tires and, on occasion, have a set of snow chains available in case you encounter snowy roads.

            Always take into account the road you are going to drive on, as when you drive without chains in an area of snow or ice, you risk losing control of the vehicle. If you are traveling on ice or snow with mixed tires and without chains, you run the risk of losing traction, which means the steering wheel will be difficult to control and the brakes will not respond as they should in the event of an unexpected situation. To prevent this from happening, we explain the different types of snow chains available and which one is best for you.

• On which wheels should you put any type of snow chain on your car?.

            Before we dive into the types of snow chains that can be fitted to a car, it is important to know which tires they should be fitted to. You need to be clear that all types of snow chains are fitted to the drive wheels.

1. In a front-wheel drive vehicle, the drive wheels are those located on the front axle.
2. In rear-wheel drive vehicles, they are on the rear axle.
3. If the vehicle is 4×4 or all-wheel drive, it is best to fit chains to all four tires. If you only have one set of two chains, it is preferable to fit them to the front axle.

• How do I know what type of snow chains my car needs based on the size of the tires?.

            Snow chains fit onto car wheels, although there are different sizes depending on the dimensions of your car's tires. You need to look at three elements:

1. Wheel diameter.
2. Tire width.
3. Tire profile.

            You can find these three details on the side of the tire. Remember to check the drive axle, as sometimes the dimensions of the front and rear wheels may be different. You can also find them in the car's technical specifications in the following format: 205/55R/16 91V. The numbers may vary depending on your car and tire size.

            As a general rule, chains are universal for wheels between 13 and 17 inches. If the tire exceeds these measurements, you will need to find specific chains that include the diameter, width, and profile of your wheels.

• Driving with chains.

            It should be noted that these snow chains, especially the most common ones, are not designed for driving at normal speeds, but are generally intended for speeds not exceeding 50 km/h, especially in the case of textile chains. In any case, even with chains fitted, it is important to continue driving with caution.

            Chains help us to have more traction in slippery conditions, but they do not eliminate the risk 100%. That is why it is always advisable to adapt to the difficult conditions caused by snow or ice and, as we say, drive calmly and always anticipate what we are going to encounter on the road, adapting our driving accordingly to terrain that is often slippery and requires us to change our mindset in some ways, as many winter driving courses teach us.

• Types of snow chains available on the market.

1.      Liquid chains.

            Although they are called chains, they are actually a spray that is applied to the tire tread to increase grip at a specific moment. Their main function is to get you out of a very specific predicament, but they are not a permitted system for driving when chains are mandatory.

            The level of safety offered by this system is very low, so its use is not recommended.

2.      Metal chains.

            These are the most commonly used, classic chains with metal links. They allow for safe driving on snow or ice and are the most economical, but they are more complicated to fit, heavy, noisy, and can interfere with the correct use of stability control or ESP. When purchasing them, check that the label states that they are compatible with these systems. It is not recommended to drive with them without snow because they damage the tire and the rim. These are the ones you should generally fit on your car when it snows and the wheels start to skid due to the accumulation of snow on the asphalt.

Ø      Advantages.

1. High durability and resistance.
2. Value for money.
3. Ideal for deep snow and ice.
4. Good traction in extreme conditions.

Ø      Disadvantages.

1)      Difficult to install for those without experience.

2)      Noise when driving.

3)      Weight.

4)      Vibrations.

5)      Can damage the rim and suspension if there is not enough snow or ice.

3.      Fabric chains or textile chains.

            Very popular due to their light weight and easy installation. They consist of a fabric cover that covers the tread of the tire. They are the smoothest to drive on, can be used with ABS and ESP, and do not damage the rim, although they do wear out more quickly. It is recommended not to exceed the speed recommended by the manufacturer so as not to reduce the durability of this type of snow chain, which is usually less resistant than metal chains. If your journey through the snow is going to be short and in areas with loose snow, this type of snow chain is a good option.

Ø      Advantages.

1.      Quick and easy installation.

2.      Compatible with ABS and ESP systems.

3.      Does not damage tires.

4.      Good value for money.

Ø      Disadvantages. 

1.      Less effective in deep snow or on hard ice.

2.      Limits maximum driving speed.

4.      Net chains or composite chains.

            These are similar to fabric chains, but in this case the cover is made of a network of plastic cables with steel studs and covered with fabric. They are quick and easy to fit, but the difference is that greater tension is used to fit them to the tire, so more force is required when fitting them. They are also more expensive than fabric chains, although they last longer. If you are going to use your car in the snow for a long time, choose this option over fabric chains. Like fabric chains, they are compatible with stability control.

Ø      Advantages.

1.      Greater resistance than textiles.

2.      Allow driving at higher speeds.

3.      Easy installation.

4.      Recommended for frequent use.

5.      Offer a smooth ride.

6.      Easy assembly.

7.      High durability.

Ø      Disadvantages.

1.      Higher price than other types.

2.      Not ideal for extreme snow conditions.

5.      Semi-automatic chains.

            Also known as spike spider chains, they consist of a fixed part that is always installed on the rim and a movable part that you can mount or remove depending on the road conditions. They are quick to install, very effective in heavy snow or ice, and highly durable. The downside is their price, which is much higher than conventional chains.

Ø      Advantages.

1.      Quick and easy installation.

2.      Perfect for everyday use.

3.      Recommended for high-end vehicles and low-profile tires.

Ø      Disadvantages.

1.      High cost.

2.      Requires specific adjustments for each vehicle model.

6.      TPU chains - Thermoplastic polyurethane.

            These represent a recent innovation on the market. These chains are lightweight and are secured using straps, creating a hardened “sole” with steel studs for better grip and penetration on ice. They usually include a specialized tool kit for installation and removal, as they are designed for short periods of time outdoors.

Ø      Advantages.

1.      Easy to install.

2.      Effective in moderate snow and ice.

Ø      Disadvantages.

1.      Limited durability.

2.      Not recommended for continuous use in extreme conditions.

• Snow chains for motorcycles. 

            Unless absolutely necessary, do not use your two-wheeled vehicle on snowy roads. Driving can become extremely difficult, with the consequent danger of falling. 

            If you have no choice but to use your motorcycle in snow, ice, wind, or rain, here are some recommendations on how to ride in bad weather. If you are going to ride in the snow, there are several options on the market, similar to those we have discussed for cars, although adapted to the size of motorcycle wheels.

1. Liquid chains.

            As with cars, this is a temporary solution that can get you out of a tight spot, but it is by no means a substitute for conventional chains and is not legal when chains are mandatory.

2. Metal chains.

            They work in a similar way to those used on cars. The chain is placed along the motorcycle tire, although unlike the former, it comes in segments rather than as a single piece. It is a practical solution, although it will not solve all your problems when driving in snow. Remember to place it at least on the rear wheel, which is normally the one that provides traction on a motorcycle.

3. Nylon straps.

            These are only for emergencies, when you need a little extra traction.

4. Studded tires.

            These are not permitted in Spain, but they are in other countries such as Norway, Denmark, Estonia, and Finland.

5. Winter tires.

            These are the most effective solution of all those mentioned. Remember to use them only when the temperature is below 7°C, at which point the grip of an all-season tire decreases, resulting in a longer braking distance, depending on road conditions and the speed of the motorcycle. 

• Implications for fleet management.

            The main consequences are cost and safety, depending on the chain we use.

            The following measures are recommended.

1. Safety.

            In a vehicle fleet, safety comes first, so it is recommended to use metal, semi-automatic, or TPU chains because they are the safest.

2. Storage.

            Chains must always be kept in the vehicle, in their cover or case, along with the assembly and disassembly instructions.

3. Maintenance.

            Although chains require virtually no maintenance, they should be checked from time to time to ensure they are in good condition, especially before winter.

4. Chain assembly.

            Chains should only be fitted when snow appears. Otherwise, they can damage the tire and rim.

5. Use of gloves.

            Wear gloves when fitting and removing chains. It is recommended that you store them together with the chains.

6. Training for drivers and mechanics in our workshop.

            Drivers and mechanics in our workshop must be trained in the assembly and disassembly of chains.

            It is recommended that drivers practice assembling and disassembling chains at our facilities.

            It is recommended that drivers take a course on driving with chains.

7. Purchasing chains.

            The chains purchased must be of good quality and easy to mount and dismount, and it must be checked that the chain is compatible with the car model.

            Don't wait until it snows; buy them in advance to avoid stock shortages and to have time to practice.

Slide 3. Thank you for your time.

            The class has developed the types of car chains, their advantages and disadvantages, and the implications for fleet management, see you soon.