What is Process Capability in PCB Problems

What is Process Capability in PCB Problems

Circuit board manufacturers and circuit board designers will explain to you what is process capability

Process capability

Process capability refers to the production quality capability of a process under fixed production conditions and stable control. Process capability index refers to the extent to which the process capability meets the requirements of product quality standards (specification range, etc.), or the actual SMT processing capability of a process under control (stable state) for a certain period of time. Therefore, before evaluating a process capability, at least the following two items should be done:

The capability of a manufacturing engineering is composed of many factors. Starting from the design of products, it includes raw materials, machines, equipment, operation methods, operators' skills, measurement equipment, inspection methods, inspection skills, etc. Any change in these factors can more or less affect its process capability. Therefore, before discussing the process capability, All these factors that may affect the process capability must be fixed first. Therefore, the so-called Standard Operation Procedure (SOP) must be formulated to standardize all steps in the manufacturing process, even the amount of materials added in each link must be specified.

When all the above factors are standardized and implemented, and the measured values of the process are in a stable control state, the process capability can be called the engineering capability of the process.

In addition, the process capability usually needs to be measured to measure its advantages and disadvantages, so it is necessary to quantify the steps in the process. For example, the printing process can be quantified into pressure, speed, temperature, printing position, etc. These values can be measured and controlled by numerical values.

When PCB manufacturers complete the process capability through the above two methods, they can usually let us know the process capability that can be achieved by a project under a certain combination, and even can be used for the following purposes:

Provide data to facilitate the design of new products or the quality improvement of existing products.

Check whether the process capability of a new or repaired equipment can be accepted.

Help us choose different raw materials, appoint new operators or adopt new operation methods.

Make an experimental plan for a production batch to adjust various production factors, and select the best combination of process parameters.

When the process capacity exceeds the specification tolerance, an appropriate center value can be set to enable the most economical production.

However, in most production processes, the quality of each process will change with the change of production factors, which will lead to failure to achieve the desired process capability. Therefore, we must regularly or irregularly control and measure the quality of each process and evaluate it. Generally, we will use control chart or Cpk control to achieve this goal.

The Circuit board manufacturer and circuit board designer will explain what the manufacturing capability is.