How is a Wheel made?

Automotive wheels are made with many different types of manufacturing processes. The performance of an alloy wheel is a direct result of the manufacturing technique employed. Wheel companies that supply to the O.E.M. market must follow certain procedures during the manufacturing process to maintain the quality and integrity of their product.

One-Piece Cast Wheels

This is the most common type of aluminum wheel. The casting of wheels is the process of getting molten aluminum inside a mold to form a wheel. There are different ways this can be accomplished and although it sounds simple, this is truly an art when done properly.

Gravity Casting

Gravity casting is the most basic process of pouring molten aluminum into a mold utilizing the earth's gravity to fill the mold. Gravity casting offers a very reasonable production cost and is a good method for casting designs that are more visually oriented or when reducing weight is not a primary concern. Since the process relies on gravity to fill the mold, the aluminum is not as densely packed in the mold as some other casting processes. Often gravity cast wheels will have a higher weight to achieve the required strength.

Low Pressure Casting

Low pressure casting uses positive pressure to move the molten aluminum into the mold quicker and achieve a finished product that has more density over a gravity cast wheel. There is a slightly higher production cost over gravity casting, but low pressure casting is the most common process approved for aluminum wheels sold to the O.E.M. market.

Spun-Rim, Flow-Forming or Rim-Rolling Technology

This process begins with a low pressure type of casting and uses a special machine that spins the initial casting, heats the outer portion of the casting and then uses steel rollers pressed against the rim area to pull the rim to its final width and shape. The combination of the heat, pressure and spinning create a rim area with the strength similar to a forged wheel without the high cost of the forging.

High Light Technology (HLT)

The High Light Technology (HLT) process uses rollers to compress and elongate the material along the barrel of a low-pressure cast aluminum wheel to obtain the desired profile. This process produces wheels that are extremely light and strong.

The flow-forming process and the HLT technologies combine to create mechanical characteristics similar to those of a forged wheel. This permits a dramatic reduction in wheel weight while enhancing structural rigidity vs. a standard cast wheel.

CNC Mill

In forged wheels, computer numerically controlled (CNC) mills add the cosmetics and the bolt circle to exacting tolerances.

Forged

Forging is the process of forcing a solid billet of aluminum between the forging dies under an extreme amount of pressure. This creates a finished product that is very dense, very strong and therefore can be very light. The costs of tooling, development and equipment make this type of wheel very exclusive and high in cost.

Multi-Piece Wheels

This wheel utilizes two or more components assembled together to produce a finished wheel. Multi-piece wheels can use many different methods of manufacturing. Centers can be cast in various methods or forged. The rim sections for 3-piece wheels are normally spun from disks of aluminum. The rim sections are bolted to the center and normally a sealant is applied in or on the assembly area to seal the wheel.