A tire is a ring-shaped component that surrounds a wheel's rim to transfer a vehicle's load from the axle through the wheel to the ground and to provide traction on the surface over which the wheel travels. Most tires, such as those for automobiles and bicycles, are pneumatically inflated structures, providing a flexible cushion that absorbs shock as the tire rolls over rough features on the surface. Tires provide a footprint, called a contact patch, designed to match the vehicle's weight and the bearing on the surface that it rolls over by exerting a pressure that will avoid deforming the surface.
An inflatable is an object that can be inflated with a gas, usually with air, but hydrogen, helium, and nitrogen are also used. One of several advantages of an inflatable is that it can be stored in a small space when not inflated, since inflatables depend on the presence of a gas to maintain their size and shape. Function fulfillment per mass used compared with non-inflatable strategies is a key advantage. Stadium cushions, impact guards, vehicle wheel inner tubes, emergency air bags, and inflatable space habitats employ the inflatable principle. Inflation occurs through several strategies: pumps, ram-air, blowing, and suction.
The contact patch is the portion of a vehicle's tire that is in actual contact with the road surface. It is commonly used in the discussion of pneumatic tires, where the term is used strictly to describe the portion of the tire's tread that touches the road surface. The term “footprint” is used almost synonymously. Solid wheels also exhibit a contact patch which is generally smaller than the pneumatic “footprint”.
Aquaplaning or hydroplaning by the tires of a road vehicle, aircraft or other wheeled vehicle occurs when a layer of water builds between the wheels of the vehicle and the road surface, leading to a loss of traction that prevents the vehicle from responding to control inputs. If it occurs to all wheels simultaneously, the vehicle becomes, in effect, an uncontrolled sled. Aquaplaning is a different phenomenon from when water on the surface of the roadway merely acts as a lubricant. Traction is diminished on wet pavement even when aquaplaning is not occurring.
The Firestone and Ford tire controversy of the 1990s saw hundreds of people die in automobile crashes caused by the failure of Firestone tires installed on light trucks and SUVs made by Ford Motor Company.
The Schrader valve is a type of pneumatic tire valve used on virtually every motor vehicle in the world today. The Schrader company, for which it was named, was founded in 1844 by August Schrader. The original Schrader valve design was invented in 1891, and patented in the United States in 1893.
Rolling resistance, sometimes called rolling friction or rolling drag, is the force resisting the motion when a body rolls on a surface. It is mainly caused by non-elastic effects; that is, not all the energy needed for deformation of the wheel, roadbed, etc., is recovered when the pressure is removed. Two forms of this are hysteresis losses, and permanent (plastic) deformation of the object or the surface. Note that the slippage between the wheel and the surface also results in energy dissipation. Although some researchers have included this term in rolling resistance, some suggest that this dissipation term should be treated separately from rolling resistance because it is due to the applied torque to the wheel and the resultant slip between the wheel and ground, which is called slip loss or slip resistance. In addition, only the so-called slip resistance involves friction, therefore the name "rolling friction" is to an extent a misnomer.
A tire-pressure gauge, or tyre-pressure gauge, is a pressure gauge used to measure the pressure of tires on a vehicle. Proper tire pressure is crucial for vehicle safety, fuel efficiency, and tire longevity. Tire gauges come in various types, including analog, digital, and dial gauges, each offering different features and accuracy levels. Tire-pressure gauges can be used both professionally and casually and come in many different sizes.
Cold inflation pressure is the inflation pressure of tires as measured before a car is driven and the tires warmed up. Recommended cold inflation pressure is displayed in the owner's manual and on the Tire Information Placard attached to the vehicle door edge, pillar, glovebox door or fuel filler flap.
A beadlock or bead lock is a mechanical device that secures the bead of a tire to the wheel of a vehicle. Tires and wheels are designed so that when the tire is inflated, the tire pressure pushes the bead of the tire against the inside of the wheel rim so that the tire stays on the wheel and the two rotate together. In situations where tire pressure is insufficient to hold the bead of the tire in place, a beadlock is needed.
A run-flat tire is a pneumatic vehicle tire designed to resist the effects of deflation when punctured, allowing the vehicle to continue to be driven at reduced speeds for limited distances. First developed by tire manufacturer Michelin in the 1930s, run-flat tires were introduced to the public market in the 1980s. They have increased in popularity over time.
A tire-pressure monitoring system (TPMS) monitors the air pressure inside the pneumatic tires on vehicles. A TPMS reports real-time tire-pressure information to the driver, using either a gauge, a pictogram display, or a simple low-pressure warning light. TPMS can be divided into two different types – direct (dTPMS) and indirect (iTPMS).
A blowout is the uncontrolled release of crude oil and/or natural gas from an oil well or gas well after pressure control systems have failed. Modern wells have blowout preventers intended to prevent such an occurrence. An accidental spark during a blowout can lead to a catastrophic oil or gas fire.
A flat tire is a deflated pneumatic tire, which can cause the rim of the wheel to ride on the tire tread or the ground potentially resulting in loss of control of the vehicle or irreparable damage to the tire. The most common cause of a flat tire is the puncturing of the tire by a sharp object, such as a nail or pin, letting the air escape. Depending on the size of the blowout, the tire may deflate slowly or rapidly.
Petroleum is a fossil fuel that can be drawn from beneath the Earth's surface. Reservoirs of petroleum are formed through the mixture of plants, algae, and sediments in shallow seas under high pressure. Petroleum is mostly recovered from oil drilling. Seismic surveys and other methods are used to locate oil reservoirs. Oil rigs and oil platforms are used to drill long holes into the earth to create an oil well and extract petroleum. After extraction, oil is refined to make gasoline and other products such as tires and refrigerators. Extraction of petroleum can be dangerous and have led to oil spills.
Inspection and maintenance of tires is about inspecting for wear and damage on tires so that adjustments or measures can be made to take better care of the tires so that they last longer, or to detect or predict if repairs or replacement of the tires becomes necessary. Tire maintenance for motor vehicles is based on several factors. The chief reason for tire replacement is friction from moving contact with road surfaces, causing the tread on the outer perimeter of tires to eventually wear away. When the tread depth becomes too shallow, like for example below 3.2 mm, the tire is worn out and should be replaced. The same rims can usually be used throughout the lifetime of the car. Other problems encountered in tire maintenance include:
A bicycle tire is a tire that fits on the wheel of a bicycle or similar vehicle. These tires may also be used on tricycles, wheelchairs, and handcycles, frequently for racing. Bicycle tires provide an important source of suspension, generate the lateral forces necessary for balancing and turning, and generate the longitudinal forces necessary for propulsion and braking. Although the use of a pneumatic tire greatly reduces rolling resistance compared to the use of a rigid wheel or solid tire, the tires are still typically the second largest source, after wind resistance, of power consumption on a level road. The modern detachable pneumatic bicycle tire contributed to the popularity and eventual dominance of the safety bicycle.
An aircraft tire or tyre is designed to withstand extremely heavy loads for short durations. The number of tires required for aircraft increases with the weight of the aircraft, as the weight of the airplane needs to be distributed more evenly. Aircraft tire tread patterns are designed to facilitate stability in high crosswind conditions, to channel water away to prevent hydroplaning, and for braking effect.
Continental Airlines Flight 603 was a scheduled McDonnell Douglas DC-10 flight between Los Angeles International Airport and Honolulu International Airport. On March 1, 1978, it crashed during an aborted takeoff, resulting in the deaths of four passengers.
Investigation of diving accidents includes investigations into the causes of reportable incidents in professional diving and recreational diving accidents, usually when there is a fatality or litigation for gross negligence.
