Dial spring support surface flatness test guide: strict regulations to ensure stable bearing

Among the numerous quality parameters of disc springs, "supporting surface flatness" is a crucial yet often overlooked factor. It directly impacts the alignment accuracy, load distribution uniformity, and long-term stability of spring assemblies. Jiangsu Sunzo Spring Elasticity understands that exceptional disc spring design and manufacturing go beyond material selection and heat treatment – they require relentless pursuit of these technical details. This article provides a detailed analysis of professional inspection methods and standard evolution for evaluating disc spring supporting surface flatness.

1、Comparison between new and old national standards: the past and present of Pingdu

Many senior engineers may remember that in the old GB/T 1972-80 standard, it clearly stipulated the parallelism requirements of the two support surfaces of the disc spring. However, in the current GB/T 1972-2005 national standard, this is not directly mentioned. Does this mean that parallelism is no longer important?

This is far from the case. While this evolution reflects evolving application standards, surface flatness of support surfaces remains a critical quality control metric for disc springs in high-end applications and demanding operating conditions. At Jiangsu Sunzo Spring Elastic, we proactively implement stricter internal quality controls than previous standards to ensure superior performance and reliability when our products are used in stacked configurations.

2、Professional testing method: the precise combination of tablet and feeler

So, how to scientifically detect the flatness of the leaf spring support surface? The standardized operation process is as follows:

1. Prepare tools: a test plate of class II accuracy and a feeler gauge with a thickness of 0.02mm.

2. Place the sample: Place the disc spring with its outer diameter support surface facing down on the inspection plate.

3. Pressure test (key step): According to the stiffness of the leaf spring, a small pre-pressure can be applied (about 2% of the theoretical flattening load Pf, and not more than 30kgf). This step can simulate the working condition of the leaf spring, so that the measurement results are more engineering meaningful.

4. Gap test: Use a 0.02mm feeler gauge to try to insert the gap between the disc spring support surface and the plate.

5. Qualification determination: The determination must meet two conditions simultaneously:

Maximum gap value: the thickness of the inserted feeler shall not exceed the allowable value of the corresponding specification (refer to Table 1 of the original old standard).

Total arc length of gap: the total sum of all the arc lengths with gaps shall not exceed 1/3 of the outer circumference of the disc spring.

Only when the above two points are met at the same time, the flatness of the disc spring support surface can be judged as qualified.

3、The three crowds of elastic quality commitment: the true story in the details

Jiangsu Sunzo Spring Elastic consistently incorporates parameters such as flatness of support surfaces – which exceed national standards – into routine quality inspection protocols. This reflects our profound understanding of disc spring technology and our commitment to customer responsibility. We fully recognize that even minor flatness deviations can be amplified when multiple disc springs are used in series or parallel configurations, potentially causing equipment vibration, uneven load distribution, or premature failure.

Therefore, by choosing Sunzo Spring Elastic, you are not only choosing a product that meets the national standard of disc springs, but also our more stringent internal control standards and quality assurance system based on rich engineering experience.