The quality of plastic gears is one factor that is highly scrutinized before a gear can be utilized for machines and other devices. It is a crucial factor that can affect manufacturing processes and machine performance, even of simple machines or devices. And this is what engineers and other professionals look for before integrating a gear into a process.
The AGMA Standard
When quality control of plastic gears manufacture is talked about, the AGMA criteria is often mentioned. This is what most engineers look for when they want to know a gear’s quality, and this is also a basis that Kore Industries look to, specifically AGMA 8, when it comes to plastic gear production.
The AGMA designates a numerical unit for gears that informs engineers of its build quality. Double flanked gear tester quality personnel perform the analysis of the gear teeth along with a number of other parameters critical in a gear manufacture to defining its geometric accuracy. While the AGMA is not the only criteria that can indicate a gear’s quality, it is the choice of engineers and companies in the U.S. Other organizations that provide the standards for gear quality are the International Standards Organization and the Deutches Institute Normale.
Here are some key points pertaining to the AGMA standards:
- According to the AGMA 2000 A88 Gear Classification and Inspection Handbook, the accuracy of the tooth geometry is given a number from Q3 to Q15. This number is inversely proportional to its tolerance. Meaning, the smaller the quality number, the higher the tolerance.
- The numbers provided by the AGMA also indicate the type of material and the heat treatment used in gear production.
- It does not specify the quality of the materials used and the quality of the heat treatment process.
- The AGMA quality numbers are specifically intended for unassembled gears, or those that are supplied independently rather than being in an enclosed drive.
- However, since there are no other standards that can classify assembled gear drives, the AGMA is also used for such.
AGMA Quality Numbers
The quality numbers that gears are now known for indicate the precision level of the tooth shape and its concentricity. There are specific parameters that are used to arrive at a certain number.
- Parameters that Quality Numbers are based on:
- Tooth Lead or Alignment. This applies to spur or helical-type gearing. It measures the differences between the specified lead and that of the produced gear.
- Involute Profile Variation. This is the difference between the specified or nominal gear profile and the measured profile of the actual gear tooth.
- Pitch or Spacing Variation. This is the measured variation between the specified or nominal tooth location and the actual deviation around the gear circumference.
- Radial Runout. This is the variation in tooth distances from the center of location.
Now, these parameters of injection moulded plastic gears are measured using advanced equipment that indicate the variations and automatically determine the AGMA number of the gear.
At Kore Industries, the gears produced always get a higher quality number. This means our precision plastic gears are close to the actual geometry specified. And they will deliver improved functions when used. Smoother and steadier machine processes and constant gear speed at lower noise levels are just some of these. Check the attached image to see an actual test result of one of our gears. You will be able to identity the AGMA quality of the specific gear, as well as reports on the runout and tooth to tooth composite error.
If you want to know more about our plastic gears and other manufacturing processes, don’t hesitate to contact us and receive our no obligation consultation.