Reliability Testing Overview
Reliability testing is an activity carried out to evaluate the functional reliability of a product during its specified life period and under all environments such as expected use, transportation or storage. It is to expose the product to natural or artificial environmental conditions and withstand its effects to evaluate the performance of the product under the environmental conditions of actual use, transportation and storage, and to analyze and study the impact of environmental factors and their mechanism of action.
By using various environmental test equipment to simulate high temperature, low temperature, high temperature, high humidity, and temperature changes in the climate environment, we can accelerate the reaction of the product in the use environment to verify whether it reaches the expected quality in R&D, design, and manufacturing. Target, thereby evaluating the product as a whole to determine product reliability life.
Reliability test classification
Software reliability testing
Software reliability is the ability of a software system to complete specified functions within a specified time and under specified environmental conditions. Generally, the reliability of a software system can only be measured by testing it.
Hardware reliability testing
Hardware reliability testing is also called product reliability evaluation, which refers to the product's ability to complete specified functions under specified conditions and within a specified time. During the design and application process, products are constantly affected by themselves and the external climate environment and mechanical environment, but they still need to be able to work normally. This requires testing equipment to verify them. This verification is basically divided into R&D tests and trial production tests. , three parts of mass production sampling inspection. Reliability tests include: aging test, temperature and humidity test, gas corrosion test, mechanical vibration test, mechanical impact test, collision test and drop test, dustproof and waterproof test, packaging pressure test and other environmental reliability tests.
Life test is a reliability test
Reliability testing is a means of investigating, analyzing and evaluating product reliability. The test results provide a basis for fault analysis, research on corrective measures, and judgment of whether the product meets the index requirements.
According to the methods and purposes used in reliability statistical tests, reliability statistical tests can be divided into reliability verification tests and reliability determination tests. Reliability determination tests are tests performed to determine reliability characteristics or their magnitude, and are usually used to provide reliability data. The reliability verification test is a test used to verify whether the reliability characteristic value of the equipment meets its specified reliability requirements. Reliability identification and acceptance tests are generally referred to as reliability verification tests.
(1) Divided by environmental conditions, it can be divided into simulation tests and field tests under various stress conditions;
(2) Divided by test items, it can be divided into environmental tests, life tests, accelerated tests and various special tests;
(3) Divided according to the purpose of the test, it can be divided into screening test, identification test and acceptance test;
(4) According to the nature of the test, it can also be divided into two categories: destructive testing and non-destructive testing;
(5) But the commonly used classification method is to summarize it into five major categories: environmental testing, life testing, screening testing, and field use testing.
Life test plays a role in reliability test
Life test is one of the most important and basic contents in reliability testing. It puts the sample under special test conditions and measures the distribution of the number of failures (losses) over time. Because failures occur in sequence, order statistics theory can be used to analyze life test data, so that the life characteristics and failure distribution patterns of the product can be determined, and reliability indicators such as the failure rate and average life of the product can be calculated. In addition, the reasonable reliability screening process and conditions of the product can also be determined to further improve the basis for ensuring product quality.
Effective life testing program
Highly accelerated life testing (HALT) and accelerated life testing (ALT) are the two most effective reliability testing technologies used in product reliability design. Highly accelerated life testing is suitable for discovering design defects, determining failure mechanisms, and describing product margins. Highly accelerated life testing is best used when the primary failure mechanism is not due to wear. Accelerated life testing is suitable for describing the failure mechanism caused by wear, and is usually used to test the failure of the mechanism beyond the user's expectations and beyond the warranty period.
In most cases, these two methods are best used in combination. Because each method is suitable for revealing different types of failure mechanisms. The appropriate combination of the two methods provides a complete and comprehensive set of test methods for product reliability design.
Highly accelerated life testing (HALT) was first proposed by Dr. Gregg K Hobbs, president of Hobbs Engineering Company in the United States. Since the 1990s, HALT has been popularized and applied. The biggest feature of HALT is time compression, that is, simulating situations that may be encountered during the entire life of a product in just a few days.
Life test related standards
GB 2689.1-81 General principles of constant stress life test and accelerated life test methods
GB 2689.2-81 Graph estimation method for life tests and accelerated life tests (for Weibull distribution)
GB 2689.3-81 Simple linear unbiased estimation method for life tests and accelerated life tests (for Weibull distribution)
GB 2689.4-81 Best linear unbiased estimation method for life tests and accelerated life tests (for Weibull distribution)
BOTO GROUP is a professional manufacturer of various kinds of testing equipments over 30 years.
Specializing in the production of various reliability simulation environmental test chambers,
1. Constant temperature test;
2. Light aging test;
3. Ultraviolet aging test;
4. Salt spray corrosion test; } ←Click to learn more！
5. Rain test;
6. Accelerated aging test;
Meet various international standards to help you improve and upgrade your products, reduce production costs, and improve market competitiveness!
Welcome to inquire!