The question of what the part covering the wheel arch is called often arises from beginners or owners who are faced with the need to repair after winter operation. In everyday life, this detail is called differently: locker, underflag, wing or just plastic protection. But a technically competent name, floppy. It is this element that takes the brunt of the stones, sand, salt and reagents flying from under the wheels, which are generously watered by the roads by utilities.
The absence or damage of this protection can lead to serious consequences for the body of the car. Water and dirt, getting into the space above the arch, cause corrosion of metal, destroy the paintwork and can damage the elements of the suspension or wiring. Understanding what this knot is made of and why it is needed will help you keep the car in excellent condition for many years to come.
In this article, we will analyze in detail the design of the underwings, the materials of their manufacture, and also consider the nuances of installation and replacement. You will learn why standard parts often fail to work and what to look for when choosing aftermarket solutions. The right approach to protecting arches is to invest in the durability of your vehicle’s body.
Official name and functions of the element
So let's get to the terminology. The details in question are officially named floppy (or locker, from English). Locker - lock, close, close. This is not just a decorative pad, but an important part of the body protection system. The main task of the backrest is to isolate the inner surface of the wheel arch and the adjacent elements of the engine compartment or trunk from the aggressive effects of the external environment.
The functionality of this detail is much wider than it seems at first glance. It not only protects the metal from rust, but also performs an acoustic role, reducing noise from tyre rolling and gravel strikes against the body. In addition, the under-wing forms the correct airflow, removing heat from the brake mechanisms and preventing the clogging of space above the wheel with snow porridge or dirt.
In modern cars, engineers pay special attention to aerodynamics. Locker It often has a complex geometry that helps direct air currents along the side of the vehicle, reducing overall aerodynamic drag. Damage or loss of this part can imperceptibly impair the stability of the car at high speeds and increase fuel consumption.
⚠️ Note: Operation of the car without wings in winter is extremely undesirable. Salt and reagents, mixed with water, form an aggressive electrolyte that is able to burn through the metal of the arch in one season.
Manufacturing materials: from plastic to rubber
The modern automotive industry uses several basic types of materials to produce wheel arch protection. The choice of material directly affects the durability, noise insulation and cost of the part. The most common option is polypropylene. It is a tough but elastic plastic that perfectly holds its shape and withstands significant mechanical stress without breaking down.
The second most popular material is rubber and various rubber mixtures. Rubber slats are more common on commercial transport or as additional sprayers. They have a high wear resistance, but over time they can smack in the cold, becoming brittle. There are also composite materials on the market that combine the properties of plastic and rubber to achieve an optimal balance between rigidity and flexibility.
Separately, it is worth mentioning felt or fabric lockers, which can be found on some premium models of past years. They provide excellent noise insulation, but are categorically not suitable for our operating conditions due to their ability to absorb moisture and dirt, turning into a hotbed of corrosion.
When choosing a material for replacement, it is important to take into account the climatic characteristics of the region. For the northern latitudes, where temperature variations are high, The best choice is considered to be frost-resistant polyethylene or special mixtures of polypropylenewhich retain elasticity even at -40°C. Cheap plastic in such conditions will quickly crack from the first impact of a stone or when you try to remove it for engine washing.
Design features and types of fastening
The design of the under-wing depends on the model of the car and the layout of the under-hood space. They can be whole, covering the entire arch, or composite, consisting of several sections. Fixing is carried out with the help of special plastic pistons, screws or clips. The quality of fasteners often leaves much to be desired, so when replacing lockers, it is recommended to immediately purchase a new set of fixers.
In some cars, the underwings are integrated into the ventilation system. Through special holes or channels in it is carried out air intake to cool the engine or remove heat from the brakes. Violation of the tightness or integrity of such systems can lead to overheating of the nodes. Therefore, when installing abnormal parts, it is important to check the coincidence of technological holes.
There is a division into front and rear wings. The front ones often have a more complex shape, since they must bypass the steering elements, shock absorbers and engine splashes. Rear wings are usually simpler, but play a key role in protecting the sills and bottom of doors from dirt emissions from under the rear wheels.
When buying new underwings, immediately purchase a spare set of pistons and clips - old ones break down in 90% of cases, even if they look whole.
Comparison of staff and non-staff solutions
Car owners often face a dilemma: to look for an original spare part or to buy an analogue. The standard slats are usually ideal for geometry, but their quality can vary. Factories often save on the thickness of the plastic, making it thin and brittle to reduce the weight of the car and the cost of production.
The aftermarket market offers solutions with improved performance. Such slats may be thicker, have additional reinforcement or reinforced mounting places. However, there is a risk: the geometry of the non-original part can differ by several millimeters, which will lead to difficulties in installing or the appearance of creaks when moving.
Below is a comparative table that helps to determine the choice:
| Characteristics | The standard wing | Non-standard (quality) | Unregular (cheap) |
|---|---|---|---|
| Geometry accuracy | Perfect. | Tall. | Low (requires further development) |
| Thickness of material | Standard (often thin) | Enlarged. | Different, often brittle |
| Price. | Tall. | Medium | Low. |
| Term of service | Medium. | High-pitched | Low. |
When choosing an analogue, be sure to check the availability of quality certificates and reviews of other owners of your car model. Cheap plastic can produce an unpleasant odor when heated or deformed by heat from the exhaust system if it passes near the arch.
The process of replacing the backing with your own hands
Replacing the backrest is a procedure that can be performed independently in garage conditions. It does not require complex special tools, but requires accuracy and compliance with a certain sequence of actions. The main rule is not to use excessive force, so as not to damage the fastening holes in the body.
Before the start of work, the car must be prepared. The machine should be installed on a flat platform, fixed with recoil stops and, if necessary, lift the desired side with a jack. For ease of operation, it is better to remove the wheel, although in some cases it is enough to simply turn the steering wheel to the stop.