The cost calculation method for circuit boards typically takes into account various factors, such as different processes and material handling, with quotations usually expressed per square meter. Naturally, specialized custom materials and specific process requirements can lead to price adjustments, all of which fall under cost accounting.
Cost = material + labor + manufacturing cost
What materials are included?
The PCB manufacturing process is lengthy, offering significant opportunities to manage production costs. These costs encompass: raw material management, utility consumption, scrap rate management, process oversight, and more.
1. Raw material management
For identical boards, the entity that uses the least materials to achieve completion will incur the lowest production costs. Controlling material usage involves minimizing rework and employee waste rates. While many factories have Production Management Control (PMC) departments to regulate material usage, this often addresses symptoms rather than the root cause. If materials are insufficient, production must continue, ultimately leading to the need for additional supplies.
To effectively address the root cause, it is essential to enhance employee proficiency, improve supervisory management skills, and refine process design. A stringent management system coupled with efficient operational methods can significantly reduce human errors. It is advisable for critical positions, such as process designers, production supervisors, and MI authoring engineers, to be filled by experienced personnel.
2. Water and Electricity Control
The judicious use of water and electricity is crucial, especially during peak seasons. Power shortages are common, with many areas implementing power curtailment measures. Machines must be shut down when not in use. Proper electricity management can lead to substantial cost savings.
Production planners should be well-versed in technological processes, work closely with the production and marketing departments, and maintain frequent communication to obtain timely information for effective production planning.
3. Scrap Rate Control
Dealing with scrap boards is regrettable, particularly given the rising costs of copper and materials, alongside declining PCB profits. A high scrap rate adversely impacts business economics. To manage this issue, we must develop an improved operating and management system that accommodates employee oversights and material variability. Key strategies for controlling the scrap rate include:
(1) Raising employee awareness about the value of circuit boards, ensuring they handle them with care. Employees should not perceive our products as low-cost or inferior; this mindset will influence their treatment of the boards. For instance, we should emphasize the proper two-handed technique when handling boards, fostering an appreciation for their value.
(2) The QA MRB (Material Review Board) plays a critical role. This reviewer must possess a strong sense of responsibility and familiarity with all processes. If a board is salvageable, the reviewer should identify it; if not, it is a waste. A misjudgment—allowing a non-salvageable board to proceed—can lead to further waste in subsequent processes.
(3) Continuously adopting new technologies and exploring the most effective working methods can help mitigate employee errors.
(4) All employees should be informed of the monthly PCB scrap rate, making them aware of the benefits associated with reducing it. Regularly summarizing the reasons for scrap will help them understand how our boards are discarded.
A high-quality PCB relies on careful material selection and meticulous execution of each process, leaving no room for negligence. The cost of materials and the precision of processes directly influence the final pricing of the circuit board.
