Technical Library | 2015-12-14 13:40:04.0
A Manufacturing Execution System (MES) is a software program that manages and monitors production work in a factory. The MES controls and monitors all manufacturing data in real time, so there is no guesswork as to the status of any given job, machine, operator, etc. The focus is on short-interval scheduling (shift or day) with an emphasis on optimizing the distribution of work orders. Larger manufacturers have employed MES’s for years but many small to medium sized enterprises (SME’s) have yet to adopt such systems. The benefits of using an MES are many. Looking forward, I predict that even the smallest manufacturing companies will employ MES systems in the future.
Technical Library | 2012-04-05 22:53:10.0
In this paper we show how hybrid control and modeling tech-niques can be put to work for solving a problem of industrial relevance in Surface Mount Technology (SMT) manufacturing. In particular, by closing the loop over the stencil printing process, we ob
Technical Library | 2019-05-01 23:18:27.0
Moisture can accelerate various failure mechanisms in printed circuit board assemblies. Moisture can be initially present in the epoxy glass prepreg, absorbed during the wet processes in printed circuit board manufacturing, or diffuse into the printed circuit board during storage. Moisture can reside in the resin, resin/glass interfaces, and micro-cracks or voids due to defects. Higher reflow temperatures associated with lead-free processing increase the vapor pressure, which can lead to higher amounts of moisture uptake compared to eutectic tin-lead reflow processes. In addition to cohesive or adhesive failures within the printed circuit board that lead to cracking and delamination, moisture can also lead to the creation of low impedance paths due to metal migration, interfacial degradation resulting in conductive filament formation, and changes in dimensional stability. Studies have shown that moisture can also reduce the glass-transition temperature and increase the dielectric constant, leading to a reduction in circuit switching speeds and an increase in propagation delay times. This paper provides an overview of printed circuit board fabrication, followed by a brief discussion of moisture diffusion processes, governing models, and dependent variables. We then present guidelines for printed circuit board handling and storage during various stages of production and fabrication so as to mitigate moisture-induced failures.
Technical Library | 2018-03-15 07:23:35.0
The SMT assembly process is continuously challenged by the factors which enhance circuit board performance and limit productivity. The pick and place and reflow systems reflect these driven issues by adding more and more controls to their systems, but the fact is one of the age old processes continues to operate within the same rules since the dawn of the SMT assembly world: The SMT screen printing. (...)This paper showcases a new stencil process that was discovered by reverting to the basics:understanding the reason for each stencil material process, focusing on detailed finishes and a disciplined aperture design process, maintaining original designs, and making the correctly designed apertures to control the paste deposition. The test results drove us to focus the efforts on the aperture walls In this paper we will demonstrate with lab tests SMT process results howthe improved paste release results in improved SMT print process performance and its positive impact on SPI yields and EOL performance.
Technical Library | 2019-12-12 02:43:44.0
Today we discuss the reason that causes temperature humidity chamber to alarm,In most cases, the equipment alarm is caused by the improper operation in the process of use, which mainly includes following reasons:that are refrigeration system, temperature system and circulating system. First, Refrigeration system 1, refrigeration compressor overpressure alarm. If the refrigerant pressure exceeds the set value, it will stop and alarm at the same time. At this time, the fault must be eliminated and then manually reset. 2, short phase power supply, phase sequence alarm. When the external power supply of the equipment is out of phase or the phase sequence is changed, it will stop and alarm at the same time. 3. The circulating cooling water is short of water to alarm. When the water pressure of the cooling circulating water system is insufficient, it will stop and alarm at the same time, and it must wait for the fault to be eliminated and reset at the same time before it could run normally. 4, refrigeration compressor overheating alarm. When the coil of the compressor is overheated and the power supply of the line is not normal, it will stop and alarm at the same time. Second, Temperature system 1, the overtemperature alarm in the chamber. The sensors in the channel and the sample area are equipped with overtemperature protection devices, and there are also overtemperature protecter on the control panel. When the temperature in the working chamber exceeds the setting value on the controller, it will stop and alarm. 2. sample overtemperature protection. When the temperature in the sample area exceeds the protection temperature set by the controller, it will stop and alarm at the same time. The overtemperature protection of the sample is divided into upper limit protection and lower limit protection, which can be set according to the demand, Third,Circulating system 1. The alarm is caused by the overheating of the circulating fan. When the coil of the fan is over-heated, the alarm will be stopped at the same time. 2. The fan over-current alarm. When the current of the fan exceeds the allowable value, the alarm is stopped at the same time, and the normal operation can only be carried out after the fault maintenance of the overcurrent is completed. This is what we talk about today,if you have more questions,let us know.
Technical Library | 2015-06-04 19:10:47.0
Integrators and designers of high-reliability systems exert little or no control over component-level plating processes that affect the propensity for tin whiskering. Challenges of how to assure long-term reliability, while continuing to use COTS parts plated with pure tin, continue to arise. An integrated, quantitative, standardized methodology is proposed whereby mitigation levels can be selected that are appropriate for specific applications of pure tin for given end-uses. A system of hardware end-use classification is proposed, together with recommended appropriate risk mitigation approaches. An updated version of the application-specific risk assessment algorithm is presented together with recommended thresholds for acceptability within the context of the hardware classifications.
Technical Library | 2023-11-20 17:59:32.0
Quality control at Mentzer Electronics in Burlingame, California, includes tracing electronics assembly issues using a Metris XT V real-time X-ray inspection system. This electronics X-ray inspection system allows quality engineers to intuitively navigate through the internal structure of assembled PCBs. In the rapidly evolving electronics industry, Mentzer Electronics uses the acquired insight to speed up and fi ne tune manufacturing processes. Real-time X-ray guarantees that no hidden defects remain in products when turning them out to customers nationwide.
Technical Library | 2020-06-19 19:08:14.0
The designs of electronic devices and systems are being continuously improved by becoming smaller in size and faster in communication speed. The potential risk associated with these specific design improvements will be an increase in power density and, consequently, a greater risk of thermal problems and failures. At the same time, the prevailing use of circuit boards integrated with power devices such as motor controllers and drivers, light-emitting diode (LED) lighting modules, power supplies, and amplifiers, and regulators for TV, etc., drive to the use of a proper thermal management system while designing these kinds of printed circuit board (PCB).
Technical Library | 2007-05-17 16:44:37.0
In the quest for quality, selecting the right Statistical Process Control (SPC) Software system doesn't boil down to a simple functional "fit-to-requirements" anymore. Once the expert domain of highly focused, independent software developers, the competitive landscape has changed dramatically with the influx of big-name ERP software providers who are aggressively promoting integrated quality modules within an all-encompassing business application framework.
Technical Library | 2013-11-06 06:39:05.0
The set up of a turnkey conformal coating production line or facility, whether it is a batch or inline process, has many similar characteristics. Whether the coating application is based around a high volume selective coating robot, a batch dip coating system or a spray booth, the process requirements tend to be the same. This bulletin reviews the potential needs of the facility, including the process controls, environmental needs and health and safety issues and provides some starting points for a new facility.