AmTech International supplies this blower shaft for a large multinational provider of air-conditioning and refrigeration solutions. This hot-rolled shaft is made from unhardened carbon steel AISI 1018. This machined component supports the fan, a key component that moves air through a roof-top air-conditioning unit.
An electric motor turns the fan assembly, which creates a one direction air flow. The blower fan drive is an indirect-drive type, with the drive belt acting as the intermediary link between the driving motor and the driven fan.
Indirect drives, or belt drives, are traditionally the most common drive type employed in commercial air-conditioners, as they require less complex maintenance and provide greater flexibility with respect to service factors.
Inspection, Cutting and Straightening
After the initial inspection, the shaft is cut to the required length and then straightened on the straightening machine.
Turning and Milling
The shaft is then turned in the CNC Machine Center and chamfered at 1.5X45º (tolerance ± 0.012”) at both ends. Lastly, a keyway is milled at one end of the shaft.
The pre- grinding process is necessary since we are holding 0.0003” tolerance on the outer diameter (OD) throughout the length of the part. In addition, it ensures that heat burns and other related stresses are minimized. Lastly, pre-grinding is especially required when the shaft has been previously heat treated.
We skin 0.0002” of the material via centerless grinding to achieve the precise tolerance of the part.
We analyze the process capability of each process (the minimum tolerance at which the machine is expected to work and produce no defectives under the specified conditions), both for keyway length and depth. Process capability ratios Cp, Cpk, Ckm and PPM (defective parts per million) are calculated.
At each stage of the blower shaft manufacturing process, the product is 100% inspected for every dimension and spec to ensure that the machines are producing parts that are within specs. We collect hourly/daily/weekly data from these inspections and use these in SPC studies as lot controls.
Washing, Rust-Proofing and Packaging
The shafts are washed manually and entirely coated with rust-inhibiting oil. The shafts are then individually packaged in a container such that no rusting, bending or any damage occurs during shipping and handling, from point of manufacturing to final assembly.
AmTech International’s focus on quality performance and reliability ensures that the shafts we manufacture can be used in HVAC systems across the world. Contact us today to learn more about our capabilities and how we can help you meet your shafting needs.