Pulse Check on Value-Added Testing

Modern Casting Staff Report

Providing various types of material testing represents an important service foundries bring to their value proposition in the metalcasting marketplace. An emerging new trend occurring in some foundry testing and quality departments is equipment redundancy––meaning, they have backup equipment in house in case of a catastrophic failure of an important measuring device, according to Tom Bloomer, senior sales & marketing manager, USA, at AFS Corporate Member Spectro Analytical Instruments.

“Redundancy has its payback, although this raises the initial cost of operation when two instruments are in use for both acquisition cost, maintenance and service upkeep,” he said.

Another major foundry trend Bloomer cites is the advent of a greater, more aggressive focus on testing increased volumes of material from foreign suppliers. 

“Many foundries are adding or increasing the number of mobile Arc/Spark analyzers so they can quickly test materials before or while they are off loaded,” he said.

Bloomer notes that foundries demand fast, accurate elemental analysis of metals. 

“The top three challenges they face are (1) ensuring incoming materials meet the specifications they require and what they believed they purchased, (2) performing in-process testing to maximize efficiency and (3) final quality inspection to guarantee they are producing the best product. Iron, nonferrous, and processing or casting operations alike require productivity, traceability, and profitability at every step. Also, it’s important to find an analytical instrument that can perform all these tasks that is reliable and easy enough to use for plant operators.”

When evaluating testing equipment, foundries should consider the history of the equipment in the field, said Bloomer––the number of installations, success stories, and overall experience of a manufacturer offering spectrometers, for example. He adds that longevity and support for the equipment is also a key factor to ensure the unit continues to perform to factory specifications. 

Bloomer also recommends partnering with a company that has factory-trained and a dedicated direct service department. 

“The initial cost of an instrument is always important along with the continued cost of operation,” he added. “Even though it is attractive to look at the lowest cost option when making a purchase, it is more essential to choose the instrument that can offer long-term reliability and optimum performance to get the most out of the investment and to keep the operation running smoothly.”

Spectrometer Insights

Bloomer pointed to recent technology developments from Spectro, including the SPECTROMAXx LMX10, which utilizes state-of-the-art, high-resolution CMOS detector technology with air optic covering wavelengths from 233 nm to 670 nm. An added UV optic handles a lower spectral range, from 120 nm to 235 nm. This includes a new capability to analyze oxygen (O) in copper. The new option analyzes relevant wavelengths to 766 nm, covering potassium. 

This 10th-generation SPECTROMAXx features completely new factory calibrations, with extended calibration ranges and element selections, optimized source excitation parameters, and improved limits of detection (LODs). As an example: For iron, aluminum, and copper matrices, the analyzer improves on its already impressive performance with 30% to 40% better LODs. 

SPECTRO has also just introduction a new SPECTROCHECK model that offers high performance and ultimate affordability. This latest model combines even lower cost of ownership with continued precision, stability, and outstanding analytical performance. Ultra-fast, one-sample standardization––based on SPECTRO´s Intelligent Calibration Logic (iCAL)––saves an average of 30 minutes per day. Its new argon-saving features allows total flow shutoff during downtimes, and 70% less argon consumption during standby. A redesigned, space-saving housing is 35% more compact, and configured with even greater accessibility for easy, safe functionality and maintenance.

Temperature Testing

Foundries face various challenges when providing value-added services related to temperature testing, according to Giulio Zini, global product manager at Marposs.

“The top three challenges are often related to maintaining quality and consistency, managing costs, and meeting diverse customer requirements,” he said. “In the era of giga casting, all this is even more accentuated, because no one has experience with such large presses. Costs have multiplied and process parameters have changed completely.

Collecting data in the process becomes fundamental to understand what is happening and to prevent scrap production, which has never been so expensive.” 

Zini, whose company specializes in temperature monitoring of dies for light alloy casting, says most process engineers would agree that many casting quality issues can be traced to thermal-related causes. 

“The thermal factors in die casting include the temperature of the alloy used for casting, the temperature of the die itself, and the temperature of the die casting machine,” he said. “Each of these must be kept at an optimum temperature range to ensure the highest part quality. If the temperature of the molten metal is too hot for the mold, it could damage it by causing premature heat checking on the mold steel. If the mold temperature is too cold, it could drop the temperature of the metal too quickly as it flows into the mold and cause defects, such as greater porosity or misruns on the casting surface.”

To keep the process controlled from a thermal point of view, Zini says thermoregulation systems play a fundamental role. 

“However, thermography represents the only technical solution capable of optimizing the functioning of the thermoregulators and the spraying phase of the lubricant-release mixture,” he added.
Marposs says its Total Thermal Vision (TTV) technology is specifically designed to provide an effective solution for checking temperature distribution across the mold surface, ensuring correct solidification of the aluminium, Zini explained.

TTV automatically communicates with the machine for full integration inside the 4.0 smart manufacturing cell, he said. Without affecting the cycle time, Total Thermal Vision monitors the die temperature distribution for every shot. 

“In summary, TTV can improve the process by reducing scrapped parts, which means lower operating costs and high customer satisfaction in terms of part quality,” Zini said.

“Furthermore, it extends the life of the molds, which are affected by delta temperature variations in every cycle, and it optimizes the sprayer action in terms of lubricant composition and cycle time duration in HPDC processes, as well as the thermoregulator functioning.”