What is the difference between cycle time and throughput? Or t = ct + o.
We have heard the terms "cycle time" and "throughput" throughout the industry. Is there a difference? Are they interchangeable in·ter·change·a·ble
That can be interchanged: interchangeable items of clothing; interchangeable automotive parts.
in ? And, most important, which one really matters to a production engineer?
Let's start with cycle time. For the printing process, cycle time is the total time required to perform a specific set of activities to achieve the primary function of the process. In this case, it includes board load, raise to vision height, fiducial fi·du·cial
1. Based on or relating to faith or trust.
2. Relating to or characteristic of a legal trust; fiduciary.
3. Regarded or employed as a standard of reference, as in surveying. alignment, raise to print height, squeegee lowering (if required), lower to transport height and board unload To remove a program from memory or take a tape or disk out of its drive. . The total time to move the board into the machine, perform the required tasks and move the board out of the printer is cycle time--and it varies greatly depending upon the type of printer selected.
Cycle time is a common specification for benchmarking printing systems because it can be used as a quantitative comparison between platforms. But it is really just a term that marketing folks use to say their product is faster than the competition's; it really does Warren Trotter, better known as Really Doe, is an American rapper from Chicago, Illinois. He is affiliated with Kanye West and his G.O.O.D. Music family and label. Discography
Before we answer that question, let's review the term throughput. Throughput is a measurement of the total processing time to print the printed circuit board and optimize the quality of the print. This is a sum of the cycle time (all the activities noted above), the print stroke and overhead functions such as wiping, paste dispensing and inspection functions. In other words Adv. 1. in other words - otherwise stated; "in other words, we are broke"
put differently , throughput is the sum of all the required steps to turn a bare PCB PCB: see polychlorinated biphenyl.
in full polychlorinated biphenyl
Any of a class of highly stable organic compounds prepared by the reaction of chlorine with biphenyl, a two-ring compound. into a quality board that is ready for the next step of the manufacturing process.
So, which is more important? Since the goal of every production line is to produce high quality boards, throughput is actually the metric that should be used to compare printing systems. Cycle time is only a component of what is important; throughput is the measurement that will really tell how quickly a line will actually produce quality boards. The overhead variables of wiping, paste dispensing and inspection functions have a huge impact on the quality and the pulse rate pulse rate
The rate of the pulse as observed in an artery, expressed as beats per minute. of the process: maximizing throughput rate Throughput rate is an obsolete term in the terminology of automated chemical analysis. It may mean either:
1. ^ International Union of Pure and Applied Chemistry. "throughput rate". should be the ultimate goal for every production line.
To accomplish this task, the focus of all electronics manufacturing This article presents a typical manufacturing process of an electronic assembly. Component manufacturing
Components such as resistors, capacitors and integrated circuits are generally made by specialized contractors. operations should be to identify, evaluate and implement methods, procedures and tools that will optimize the amount of "good products" that are built each day. There is a definite balance between product cycle time and the quality of that product. Producing defective products to achieve a specified cycle time is certainly not acceptable, nor is slowing the process to an unacceptable rate to minimize every possible defect. We must understand and optimize this balance to optimize the throughput of quality products.
What equipment features are available to help us achieve this goal? On sophisticated solder paste Solder paste (or solder cream) is a mix of small solder particles and flux. It is used extensively in the automated soldering processes wave soldering and reflow soldering. printing equipment, there is two-dimensional (2-D) and three-dimensional (3-D) post print inspection, stencil stencil, cutout device of oiled or shellacked tough and resistant paper, thin metal, or other material used in applying paint, dye, or ink to reproduce its design or lettering upon a surface. wiping and stencil vacuum cleaning, automatic board support placement systems, board-to-stencil alignment systems, and other options that reduce process defects and cycle time. These features can help improve the final product quality but, with current printing solutions, impact the final throughput.
When considering the purchase of new process equipment, take into consideration the balance between those two important goals: throughput and quality. Remember: cycle time is important but it is just a subset of throughput. What really matters is how many good boards can be produced over a period of time. Maximize throughput, and you maximize profitability.
Joe Belmonte is project manager, advanced process development, at Speedline Technologies (speedlinetech.com); firstname.lastname@example.org.