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Reliability Standard Compliance Product Testing

As a leader in reliability compliance testing, Keystone Compliance assists equipment manufacturers with regulatory standard testing. Meeting the standard testing requirements can be challenging. Not only do we understand the challenges, but we help guide companies through the process.

Keystone’s testing engineers streamline the process and assist companies to achieve the compliance they require. Keystone takes pride in providing the peace of mind that all of your unintentional radiator testing needs will be met. Our expert test engineers work with clients to quickly develop appropriate and concise test plans.

Request a quote to receive expert reliability compliance testing services tailored to your specific needs. Ready to get started? We are. Contact us to see why so many companies work with us to achieve their product compliance testing needs. 

Summary of Reliability Compliance Testing

Reliability testing is the process of determining potential problems with the design of a product while it is in the design stage. The goal of reliability compliance testing is to provide confidence and insight into the product’s ability to meet its reliability requirements. Requirements are to be carried out over the entire expected lifespan of the product.

Before testing, it is up to the manufacturer to define what a product failure may look like within their field.

The reliability test program includes several qualification tests based on the type of product, the environment within which it is expected to operate, and estimated product weaknesses. Reliability is calculated by finding the probability of products that did not fail, divided by the total number of products being tested. 

Bathtub Reliability Curve

An important aspect of reliability testing is the bathtub curve. This curve illustrates the likely failure rate of a population of products during their lifetime. The data given in this curve assists manufacturers anticipate failures and prevent them from occurring. Furthermore, the bathtub curve defines three specific periods where reliability is put into effect.

               Infant Mortality Period – The first stage of the bathtub curve is when defects in products are identified and discarded. Thus, the infant mortality period is at a decreasing failure rate.

               Normal Life Period – The normal life stage of the bathtub curve is generally classified as a low and constant failure rate. Additionally, failures are more predictable in this phase.

               Wear-out Period – This is the final stage of the bathtub curve and a product’s life. Generally, failures tend to increase due to age and usual wear and tear. 

Scope of Reliability Regulatory Compliance

MIL-HDBK is a great resource for establishing a reliability test program. This handbook provides test methods, plans, and environmental profiles which are used in reliability testing during the development. This information is also used in the qualification and production of systems and equipment.

               MIL-HDBK-781: Handbook for Reliability Test Methods, Plans, and Environments for Engineering, Development, Qualification, and Production.

Even though MIL-HDBK-781 is designed for military contracted procurements, many of the test plans, methods, and environments can be customized to suit other products and equipment. This includes a broad range of commercial products. MIL-HDBK-781 consists of guidance on the following categories of equipment:

Category 1.         Fixed-ground equipment

Category 2.         Mobile ground equipment

  • Wheeled vehicle
  • Tracked vehicle
  • Shelter configuration
  • Manpack

Category 3.         Shipboard equipment

  • Naval surface craft
  • Naval submarine
  • Marine craft
  • Underwater vehicle

Category 4.         Equipment for jet aircraft

  • Fixed-wing
  • Vertical and Short Takeoff and Landing (V/STOL)

Category 5.         Turboprop aircraft and helicopter equipment

  • Turboprop
  • Helicopter

Category 6.         Missiles and assembled external stores

  • Air-launched missiles
  • Assembled external stores
  • Ground-launched missiles

Reliability Standard Testing Capabilities

Keystone Compliance is an accredited test lab with expertise in reliability conformance testing. We assist manufacturers in determining their product’s reliability by offering the following testing called out in the MIL-HDBK-781.

Electrical Reliability Testing

Electrical Stress includes equipment ON-OFF cycling. This testing also includes operation in accordance with the specified operating modes and duty cycles. Lastly, input voltage variations above and below the nominal operational value are also covered.

Vibration Reliability Testing

Vibration Stress includes testing to levels and profiles tailored to the specified intended application of the equipment. The setup considers the mounting location and the classification category for field use. The factors considered in the definition of realistic vibration stress include: 

  1. a) type of vibration (sine sweep, complex, or random);
  2. b) frequency range;
  3. c) amplitude; and
  4. d) manner and axis of application.

The intent is to produce a vibration response with a magnitude, frequency range, and duration similar to the field service environment and mission profile.

Thermal Reliability Testing

Thermal Stress provides a realistic simulation of the actual thermal environment that the equipment experiences in the service application. The factors considered in the definition of thermal stress include:

  1. a) starting temperature (heat soak. cold soak) and turn on (warmup) time;
  2. b) operating temperature (range, rate of change, and frequency of change);
  3. c) number of temperature cycles per mission profile; and
  4. d) cooling airflow (rate and fluctuation).

Humidity Reliability Testing

Humidity Stress is often introduced during the temperature cycles to produce visible condensation and frosting or freezing. This test occurs when such conditions can be expected in field service.

Expert Reliability Laboratory Compliance Testing

Reliability testing is an important step in determining the potential weaknesses of a product. It is just one of the climatic testing services we offer and our lab is fully equipped with the necessary equipment.

We have extensive knowledge in environmental testing, including vibration, temperature, fungus, solar radiation, pyroshock, and immersion. This allows us to provide critical product performance feedback to manufacturers seeking lifecycle analysis.

Contact us today and learn how we can work together to meet your standard compliance and reliability testing needs.