By Mike Hastings, Brüel & Kjær Vibro

Chatter vibration can affect both the quality and production capacity of cold-rolled steel if it is not properly monitored and reduced. Third-order octave chatter is a self-generating resonance caused by the inter-reaction of the strip and mill, and can quickly reach destructive proportions if the speed is not reduced quickly enough. Fifth-order chatter is also a resonant condition, but it is most often excited by machine defects that can result in visual barring of the strip if the source of the excitation is not removed. Arcelor's (now Liberty Steel) cold-rolling mill in Tilleur, Belgium, has a five-stand tandem mill that is prone to third-order chatter and a four-stand tandem mill that is subject to fifth-order chatter. Brüel & Kjær Vibro’s vibration monitoring system was successfully used at the Tilleur location for both machine condition monitoring and product quality control of their tandem mills. 

BACKGROUND

Global steelmakers are compelled to become more competitive. Although the overall world steel consumption is steadily increasing, individual mills are producing smaller lot sizes with more diversified products. This, plus faster production order processing and increasing quality requirements, put special demands on production machine uptime and maintenance. The speed of production and the condition of the cold-roll tandem machine components can limit the capacity and quality of production. The cold-rolling mill in Tilleur had set out to meet these challenges by implementing a comprehensive and integrated monitoring strategy. 

THE COMPANY

The Tilleur cold-rolling mill is one of several plants involved in cold rolling and finishing processes in the Liége area. The Tilleur plant imports hot-rolled coils from mills in France and Luxemburg, and produces cold-rolled, full-hard mild carbon steel coils that are exported to nearby plants for further processing (galvanizing, annealing, tinplating and polymer coating). The coils are used in the packaging, appliance and automotive industries. As the only cold-rolling mill in the Tilleur area, the other finishing and coating companies are completely dependent on it. The four-stand, four-high tandem mill is used for making a single product for the automotive industry, but the five-stand mill is used for a range of different thin-gauge strip products for the packaging and appliance industry (mostly tinplate).

SURFACE CONDITION

Thin, cold-rolled steel is a surface-critical product with little tolerance for surface defects. There are two primary sources for steel product surface defects: Surface roll defects and chatter vibration. Defects on the rolls will directly transfer to the strip. The distance of the marks will be constant, no matter what speed the strip is moving. Roll defects could be caused by such factors as grinding faults in the roll itself, or deformation caused by the hydraulic clamping system. 

The steel strip surface can also be visually or physically affected by roll vibrations called chatter. These vibrations are speed related, meaning the vibration changes as the strip speed changes. Chatter vibration is the result of a backup or work-roll resonance in one or more stands of the cold mill, which is excited by the elastic properties of the steel itself and/or by external forces from the machine. 

There are four primary vertical vibration modes of a roll stand with four rolls. Only the second and third vibration modes can affect the surface quality of the steel, also known as the third- and fifth-octave vibration modes.

THIRD OCTAVE

The third-octave chatter vibration occurs at 110-170 Hz, which is the natural frequency of the backup rolls that resonate out of phase. It is a self-excited vibration instability condition that is created by the interaction of forces between the elastic strip together with the resonant characteristics of the mill structure in the form of a positive feedback loop. It is a function of the inter-stand properties of the steel product such as the strip tension, thickness, strip speed and other factors such as the type of steel, strip width, amount of gauge reduction, friction factor, roll force, roll bite, and lubrication.

The build-up of vibration at the natural frequency of the mill is regenerative and therefore can reach destructive proportions in less than 5 seconds. It can result in unacceptable thickness variations of the strip and even strip rupture. 

The primary method of control is reducing the strip speed, but the vibration levels can also change when other process changes are made such as the roll bending forces. Reducing strip speed has a negative effect on productivity, but it saves money by reducing the number of coils that are rejected, and by reducing downtime associated with strip ruptures and damaged rolls.

FIFTH OCTAVE

The fifth-octave vibration chatter occurs at 550-650 Hz, which is the natural frequency of the work rolls that resonate in phase. It generally occurs in the highest speed stands. If the vibration level is not reduced, it can spread to the other stands via the strip. There are many potential causes for exciting the fifth-octave vibration. It is sometimes necessary to perform modal analysis with an instrumented hammer to find the external forces that are exciting the resonance. 

Often, the external forces that excite the fifth-octave mode resonance are related to problems with the rolls, motor, shafts, bearings and gearbox. This could be grinding the rolls with small imperfections, or faults in the roll machine itself such as spindle and liner clearances, work roll bearing defects, hydraulic pressure system on rolls, vibration from worn pinion gears, gear mesh frequencies, passage of key ways in backup roll necks through the load zone, and unbalance.

UNWANTED ROLL MAKING

Over time, the backup rolls become marked by chatter vibration where the continued presence of the resonant vibration slowly wears transverse marks into the roll surface. The process is exacerbated if the frequency of the forced vibration excites mill resonances in the fifth-octave range. If the backup rolls are not changed at this time, the chatter-marked rolls will transfer these to the work roll and to the strip itself as transverse bands that can be seen on both sides of the strip without thickness variation. Chatter frequency can be calculated by dividing the strip speed by the banding bar spacing in like units. 

Controlling this chatter vibration level can be done superficially by changing speed or roll pressure, but it is more a question of identifying and then isolating or removing the external vibration source that is exciting the resonance frequency. Corrections must be made if it is caused by excessive journal bearing clearance or a fault in the motor, gearbox or drive assembly.

POTENTIAL SOLUTIONS

If the external frequency excitation is caused by work-roll bearing defects, there are a couple of solutions. If the bearings are exhibiting a brinelling-type fault (many points of impacts on the race), the bearing can be put on a different stand where there is no fifth-octave mode vibration until it can be replaced at a convenient time. 

If the fault is a spall (a single impact flaw on the race), this can be rotated out of the load zone. If the backup rolls have been subjected to high levels of vibration over a period of time and are marked, these will have to be replaced (this is sometimes done several times per shift). The backup rolls could also be subjected to mechanical fatigue due to prolonged operation within its resonance frequency. To prevent this, one or both rolls can be replaced to change the mass and reduce or increase the natural frequency so it will no longer be excited by the external forced vibrations.

Condition and product quality monitoring strategy

An on-line monitoring system was used for the following purposes:

• Automatic condition monitoring – Early detection of developing faults in motors, bearings and gearboxes of the rolling mills. This is not only for minimizing machine downtime and maintenance costs, but also for minimizing the source of external vibration that could excite chatter vibration, a part of the product quality monitoring function.

• Diagnosis and analysis – Evaluate the nature and severity of the developing fault so maintenance can be planned ahead of time.

• Product quality monitoring – Identify 1x and chatter vibration early before it can affect the strip quality, and evaluate the accumulated severity of the vibration over time to determine when the rolls should be changed.

Product-quality monitoring is the primary objective for using a monitoring system on a cold-roll mill. It is important to monitor chatter vibration in order to (1) optimize steel production speed; (2) reduce strip thickness variations and visual markings; and (3) reduce strip breakage and strip waste

MONITORING CONFIGURATION 

Forty transducers were installed on the five-stand mill, and 80 sensors were placed on the four-stand mill to detect and diagnose developing faults. Most of these are used for both monitoring the condition of the motors, bearings, shaft, gearboxes and rolls and also for identifying component fault frequencies that could excite fifth-octave chatter vibration.

For detecting chatter vibration frequencies, a single accelerometer is mounted on top of the backup roll pressure cylinder for those stands where there is a potential problem. The sensor would ideally be installed directly on the bearing chocks, but there is a risk that the sensors are damaged when rolls are replaced. In any case, the sensor mounted atop the stand has demonstrated that there is sufficient sensitivity to detect the relevant signals.

FAULT DETECTION, DIAGNOSIS AND CONTROL

The four-stand mill is running the same product at a constant speed and constant process conditions, and the strip thickness is greater than the products rolled by the five-stand mill. There is little risk for third-octave mode chatter vibration to occur on this mill, but it is, however, prone to fifth-octave mode vibration chatter. The frequency of interest is around 650 Hz. The main problem for analysis is understanding the mode of vibration conditions that lead to the problem. Modal analysis identified the roll resonance frequency and any external vibration frequencies that can excite the resonance frequency.

A 0.5-1000 Hz FFT spectrum and various FFT zoom spectra are used for diagnosis, determining the severity of chatter vibration and for identifying the new resonant frequency after a roll change. It can also be used to identify component fault frequencies that could excite the chatter vibration. FFTs with other frequency ranges are used for diagnosing faults of other machine components.

A 400-800 Hz bandpass measurement is used for automatic chatter detection and trending. It is useful for helping to determine when to change rolls. A 1x bandpass is also monitored to determine vibration caused by the defects in the roll itself.

The five-stand cold rolling mill produces a number of products that are all thinner than what is produced in the four-stand mill, and consequently more susceptible to third-octave mode vibration chatter. The frequency of interest is around 170 Hz. The fifth-octave mode vibration is not considered to be a problem for this rolling mill. 

The vibration levels are different for different types of steel, so the monitoring system uses different monitoring classes for the basic steel products. When a particular type of coil is being rolled, the monitoring system is informed of this by a digital signal, which will automatically monitor the vibration levels to alarm limits for that particular steel strip. This provides early alarm detection.

AUTOMATION

The automatic process control system uses several proprietary process parameters that detect the onset of the chatter vibration quickly, and reduces the strip speed accordingly. It is possible to hear the chatter vibration after it has started. Speed reduction is only a few percentage points and is required for only a few minutes at a time, so there is no significant loss of production. The chatter vibration from the monitoring system is not directly connected to the speed control system, but both the alarm information and signal are automatically sent to the operators as verification. The operator can use the system to judge the maximum “safe” speed for running surface-critical material. It is sometimes enough to change rolls, thus changing the mass of the system.

As with the fifth-octave mode vibration, there is a bandpass measurement for automatic fault detection (80-170 Hz), a 1x bandpass for detecting roll faults and a FFT spectrum for diagnosis (0.5-200 Hz). 

CONCLUSION

The Tilleur location’s primary function is to cold-roll steel coils, and the finishing plants in the area depend on the quality and reliability of this production. A machine condition monitoring system can be used for both condition and product quality monitoring of cold roll mills to meet this demand. Third-order chatter vibration can seriously affect the quality of the rolled steel and should be monitored in real time so action can be taken quickly to avoid this. The monitoring system is not interconnected to the DCS for automatically controlling strip speed to reduce third-order chatter vibration, but alarm relays and plots are used to confirm speed reduction. Early detection is important, and the monitoring system provides automatic alarming functions that can be customized for the particular product being rolled.

Tandem mill components should be continuously monitored to detect component defects and to identify potential sources of excitation for fifth order chatter vibration. These trends also provide a means for determining when back-up rolls should be changed. 

About the author: Mike Hastings is a mechanical engineer who has worked as a design and field engineer across various industries throughout the United States and abroad, before moving to Europe. He has worked with Brüel & Kjær Vibro for 31 years and has written numerous articles and papers on condition monitoring.

February 10, 2021 - Kingspan Insulated Metal Panels, Deland, Florida, has released a whitepaper designed to help building owners and architects make more informed choices when it comes to reducing embodied carbon in commercial and industrial buildings.

The whitepaper details a study conducted by architectural research and planning firm KieranTimberlake, which looked at the embodied carbon created when designing an industrial building. The firm performed a life cycle assessment of four different industrial claddings – mineral fiber insulated metal panels, insulated concrete, tilt-up concrete and Kingspan QuadCore™ insulated metal panels - used on a virtual 150,000-square-foot industrial warehouse in Philadelphia. The study used an R-value of 20, based on the building code climate zone for the area. The full cradle-to-grave analysis focused on material manufacturing, maintenance, replacement and end-of-life.

The study compared 2.5-inch-thick Kingspan KS Series panels utilizing the company’s QuadCore™ technology to 5-inch-thick mineral fiber IMPs, 12-inch-thick insulated concrete wall utilizing polystyrene insulation and 9-inch-thick tilt-up concrete wall insulated with fiberglass batts. The doors, windows, roofing and floor slab were kept the same across all materials. However, the wall assembly, vertical structure and foundations varied for the different applications.

KieranTimberlake utilized Tally, a Revit-integrated LCA tool, to generate a complete bill of materials for each type of assembly and assessed each for their impact on global warming, acidification, eutrophication, smog formation, ozone depletion and non-renewable energy demand.

In assessing the global warming potential, the study found that the building using Kingspan’s QuadCore™ IMPs had the lowest levels of all the wall assemblies - 28% lower than both the insulated concrete and tilt-up wall assemblies, which had the highest levels of embodied carbon.  That reduction in embodied carbon for just this single building scenario is the equivalent of the greenhouse gas emissions from the average car driving 27 times around the world or the CO2 emissions from burning 149 tons of coal.

“Studies show that embodied carbon alone is responsible for 11% of global greenhouse gas emissions. This analysis shows how switching out just one material can make a world of difference,” said Brent Trenga, Director of Sustainability. “The effort to reduce the carbon footprint of a building starts with the selection of materials and making more informed choices. We only get one chance to cut embodied carbon when designing a new building.”

Kingspan’s QuadCore™ is the most thermally efficient closed cell insulation core on the market (R-8.0 per inch) and was the first closed cell insulation panel to achieve FM 4882 fire certification. Kingspan panels with QuadCore™ are also GREENGUARD Gold certified and have earned Material Health Silver certification. When Kingspan panels are ordered with QuadCore™ and Valspar Fluropon coatings, the entire panel earns a Red List Free classification.

Download the full report >

May 29, 2020 - Please take a few minutes to read the following overview regarding Steel Manager III, our fully integrated metal service centre software solution. Steel Manager III (SM3), is a comprehensive, fully integrated ERP solution created exclusively for the metals industry which includes full functionality in the areas of Inventory Management, Purchasing, Quoting, Sales, Linear Nesting, Plate Nesting Integration, Inside Processing, Outside Processing, Production Scheduling, Picking, Shipping Manifest, complete Accounting, extensive Reporting, Barcoding and much more.

The flexibility of SM3 makes it an ideal solution for all metal centres, whether you are a general line distributor, or focus on pipe & tube, valves & fittings, OCTG products, tool steel, bar, plate, flat rolled products, perforated and expanded metal, mesh, wire rope, specialty steel and structural steel, architectural metals, along with any other type of metal.

Steel Manager III is all about SPEED & AUTOMATION. We program so users can get to the information they are looking for in seconds by making SM3 extremely user friendly. We automate many manual labour tasks that typically occur on a daily basis so staff can focus on what they do best, selling and servicing their customers.   

Forgers weigh options such as repair, rebuild, remanufacture or new equipment when considering options to increase capacity

March 10, 2020 - When forging operations must expand production to meet greater demand for existing parts or to add new product lines, selecting from various options to bring new equipment online can be challenging. Ultimately, the decision involves striking a delicate balance between fitting within budget constraints and accepting what can often be very long lead times.

Forging machines weigh between 25 and 300 tons and rise 10 to 25 feet above the production floor. The equipment is designed and built to last decades and it is not uncommon to find equipment from 50 or more years ago still in use.

This can be both a blessing and a curse when seeking to update production prowess. The sheer size and complexity of the machine means that items like the massive cast steel frame can take six to eight months for delivery, plus four to six months to install all the internal parts and componentry.

Given the longevity of the equipment, another option is to purchase used forging equipment and have it rebuilt or remanufactured. This can speed delivery by as much as six months and reduce the cost, but worldwide supply of used equipment is dwindling, meaning this option is limited.

The only other alternative is to simply repair out-of-commission units and/or to squeeze additional production by incorporating more automation in existing forging equipment.

Regardless of the choice, forging companies are studying each of the four options available—repair, rebuild, remanufacture or new.

Repair

The most immediate option to bring forging equipment online is simply to repair existing equipment or out-of-commission units. This often comes down to locating adequate replacement parts, which can be quite difficult.

The tremendous longevity of horizontal and vertical forging equipment can create unique challenges for a forging operation when a part they need to replace was built decades ago. Is the original equipment manufacturer (OEM) still in business? Does a drawing of the part still exist? Can a local machine shop replicate it?

“Sourcing spare parts can be an ongoing problem,” says Wade Ferguson, maintenance manager at Modern Forge Companies LLC, Blue Island, Illinois. The company operates five manufacturing facilities with over 25 production forges. “We probably run hammers tighter than what would ever be specified. And together with our high volume of forging, at times we are scrambling to make or find spare parts.”

To produce engine valves and other motorcycle parts for customer like Harley Davidson, Modern Forge uses Chambersburg (CECO) die forgers that date back to the 1980s and weigh between 20 and 50 tons.

When Ferguson heard (years ago) that Chambersburg entered bankruptcy, his first reaction was how would Modern Forge obtain parts? He had some replacement parts in inventory and was able to salvage parts from two offline units. Like other forging operations, he also sent some parts out to be reverse-engineered and machined.

This method has some unintended risk, however. Machine shops often do not have access to critical specifications about high-wear parts including the material grade of the steel, the heat-treating process used or tolerances that all were engineered specifically for that piece of equipment. The result can be parts that fail prematurely or wear much faster.

Later, when Ferguson learned that the Park-Ohio Co. had acquired the intellectual property rights to all Chambersburg and Ajax Manufacturing equipment in 2005, he contacted them. Ajax-CECO, as the company is now known, is one of the oldest manufacturers of forging equipment, having begun operations in 1875. Over a 145-year  history, the company built and put into production more than 6,000 horizontal and vertical forging machines.

By purchasing the IP, Ajax-CECO preserves and maintains the provenance of forging equipment for both Ajax and Chambersburg—including the original drawings, bill of materials and service manuals.

“They have very good, detailed information, which is really advantageous for us,” says Ferguson.

Most OEMs today also stock replacement parts using MRP systems that monitor inventory levels and track historical trends for common wear items such as friction plates, driving plates, piston heads, piston rods, rings and packings.

In addition, some OEMs like Ajax-CECO offer stocking programs for long lead time items such as main gears, centric shafts, rams, frames and anvils that most customers will not stock themselves. In this type of program, the part is held in inventory for the customer, who pays a percentage of the cost and then the balance when they take possession of the part, even if that occurs years in the future.

“Ajax-CECO is good about putting a spare part on the shelf for me and not charging full price for it,” says Ferguson.

Rebuild

A step up in order of magnitude from a repair is a rebuild of the forging equipment. In a rebuild, all high-wear items such as bearings, bushings, seals and liners are replaced to get the machine in good working condition. The frame is inspected and repaired, if necessary.

Given the extent of the work involved, however, this approach represents a significant investment in time. Rebuilds can take six months, depending on the number of components. On the other hand, a rebuild can save forging companies six months or more compared with ordering and installing new equipment.  This approach also reduces the overall cost to bring the equipment online.

Rebuilds can be approached several different ways. The forging equipment can be sent to the OEM for rebuilding; the OEM can send repair personnel to the manufacturer’s facility to rebuild equipment on site; or the OEM can supervise a rebuild by maintenance staff.  This allows the in-house staff to ask questions and better understand the operation of the equipment they are maintaining.

At its forging operation in Kearney, Nebraska, Eaton Corp. operates 26 Ajax-CECO 100-ton to 1,300-ton forging presses. Eaton produces engine valves and precision gears.

Although some Eaton plants purchase rebuilt equipment from companies like Ajax-CECO, Randy Kreutzer, Eaton’s lead maintenance manager, sees the value in rebuilding the equipment in house with components sourced from the OEM.

“I like the experience the maintenance staff gets from rebuilding the equipment. That way, when future repairs are required, the time frame to complete them is much shorter,” he says.

Eaton often incorporates automation upgrades that speed production in rebuilt equipment.  Today, many of these manual tasks are instead being replaced with robots or by integrating servos that can lift, insert and deposit materials. Even tasks such as automated tooling changes can be completed with the push of a button.

By doing so, tasks that were once performed manually—such as moving heavy steel rods, pipe and other stock in and out of equipment—are now automated to improve worker safety. This creates a safer environment for forging operators and improves productivity.

Remanufacture

Sometimes only the cast steel frame of the forging equipment is salvageable, in which case all the internal components can be replaced in a full remanufacture of the equipment.  Given the extent of the work required, a remanufactured forging unit can still cost 85 to 90 percent of the cost of new equipment, but delivery time is reduced by about six months. When it is finished, a remanufactured machine comes with a new machine warranty.

In essence, a remanufacture saves the cost and the time of acquiring a new cast frame.  The frame on a 3-inch upsetter press weighing 55,000 pounds, for example, could take six months plus another month for shipping (especially from a foreign equipment builder).

“With a remanufacture, all internal parts are built to factory specs,” says Kreutzer.  “With a remanufactured unit, you don’t need the man hours to rebuild it. It can just be set in place, hooked up and is ready for forging.”

As with a rebuild, a remanufactured forging unit can include a variety of automation option upgrades.

New

While purchasing new equipment may offer a forging operator the most confidence in long-term performance and the most tailored solution to the company’s forging needs, it also has the longest lead times. Moreover, a manufacturer must plan for one year before  taking delivery of a new piece of forging equipment. But the decades of value that will be generated from the new equipment means the return on investment will be significant.

Regarding new forging presses, Kreutzer cautions that quality can sometimes be an issue when sourcing from overseas sources. “We like Ajax-CECO presses for their quality, and even prefer to rebuild that equipment instead of pursuing some other options out there that will not perform or last as long,” says Kreutzer.

New equipment also gives forgers the opportunity to take advantage of the most advanced automation options available today. For example, entire forging line “cells” can be created that include sophisticated communications that report production rates and machine performance back to company networks.

Multiple choice

Some forging operations hedge their bets by using more than one strategy. Given the shortage of available used equipment and the lead times, some customers order a new machine while another is being remanufactured. Others get quotes on new equipment while continuing to seek out used equipment opportunities as they arise.

Regardless of the approach, forging operations have a lot to consider when attempting to meet increasing production demands. Whether repair, rebuild, remanufacture or new, bringing forging equipment online requires careful consideration and foresight, as well as a more complete understanding of the options.

“You have to constantly keep a lookout for equipment, worldwide, and do your price comparisons to ensure you stay within the budget,” says Kreutzer.  “Usually when we are acquiring in new equipment, it is well into the future so we have adequate time. But there are always timelines that must be met. So we have to consider all the available options.”

200 years on and aluminum is going strong 

Aluminum has come a long way since it was first produced in 1824. A mainstay in consumer goods, machinery and equipment sectors, as well as electrical engineering and other industries, aluminum is pervasive.

Today, construction and transportation sectors account for a hefty 52% of global aluminum consumption, with automotive and aerospace applications driving the metal’s growth as never before. In North America, demand for aluminum appears to be insatiable. By 2016, the latest year for which statistics are available, demand for aluminum had hit a seventh straight year of growth, according to the US Aluminum Association. Within that seven-year period, aluminum demand grew by an impressive 41%.

Read the complete White Paper >

Background on Protective Coatings for Steel

July 6, 2016 - This paper outlines current theory on edge protection and shows how the Intercoat ChemGuard has advanced coating technology by overcoming formulation obstacles through innovative manufacturing techniques.

The use of coatings to prevent the corrosion of steel is one of the oldest and most studied areas of industrial science. Committee A05 on Metallic-Coated Iron and Steel Product considers its primary goal to promote the use of metallic and non-metallic coatings to prevent corrosion. The committee celebrated its centennial anniversary in 2006.¹ 

The ASTM centennial article includes a side bar on how metallic coatings protect steel² from corrosion. There are two mechanisms:

• Barrier Protection – A mechanism to keep water and/or oxygen away from steel
• Galvanic Protection – An electrochemical force, usually from Zinc, preventing steel from corroding by oxidizing in preference to adjacent exposed steel.
  
  

Other articles are available on the subject ^{3, 4}. This article will be primarily focused on traditional barrier protection and how breakthroughs in formulation and manufacturing techniques have led to advances in edge corrosion protection. 

Read the complete white paper >

Synapse: While EAF/AOD melting is cheap, it cannot handle the extreme loads required for US process improvement. Premium melt grades are used to ensure higher quality products for demanding applications.

Melting Processes

In the early days of melting, Electric Arc Furnace (1878) and Vacuum Induction Melting (1927) were leaps ahead in quality compared to the Bessemer and Open Hearth technologies. Argon Oxygen Decarburization (1965) and later came  Vacuum Arc Remelting (1970s). 

Electroslag Remelting was introduced in the late 1970s and is now preferred over the vacuum technologies when possible. It creates an ingot directionally solidified, and results in even lower inclusions than the vacuum grades.

Issues

Some of our products had been developed with the EAF/AOD process, and while it worked for many structural applications, it simply could not remove linear defects caused at the time of pouring the ingot. Lamellar defects such as banding and segregation could not be avoided using the standard chemistry. In high pressure environments, these defects would be found through leak down or outright failure.

Solution

To combat these types of defects, the ESR process was implemented after the EAF/AOD process to create a more homogenous and extremely low inclusion product. While it does add to the overall cost of the processing, the yield improvements and much lower rate of customer reports makes a difference overall.

Instances of linear defects reported in these revamped products have dropped, and the sales force has become more comfortable in recommending these higher quality products for high pressure service again. In many cases, we supply the higher quality product without it having been specified or asked to do so. If you want to be sure that your product is High Performance, make sure it will hold up to the pressures with a higher quality melt process such as ESR.

Originally posted on LinkedIn by Jeff Kirchner, COO, Manufacturing Director at High Performance Alloys, Inc. >

A Metal Buyers Guide to Industry Terminology

December 2014 - Although purchasing metal would appear to be a simple, straightforward task, the alphabet soup of specs, approvals and overall jargon can make it a bit overwhelming. This guide has been prepared to give you the ‘Cliff Notes’ on buying metal.

EQ Coatings: Codes, Standards and Corrosion Protection
Webinar Originally Presented on Oct. 15 and 17, 2013 by: Bill Capizzano, President Chemcoaters, LLC & Eco-Green Coatings, LLC Input from Patrick Ford, P.E. Matsen Ford Design, Technical Director, SFIA Presentation converted to paper by Bill Capizzano on June 13, 2014

Practical Tips to Improve Your Operational Efficiency

Everyone is looking for tips on how to improve their business. United Performance Metals has observed first-hand what leading manufacturers are employing as best practices. As a company with over 35 years of experience serving the needs of metal fabricators, we’re sharing the most effective tactics observed in the field. Though they may not seem revolutionary, their impact on efficiency is definitely worth sharing.

Read the entire Practical Tips to Improve Your Operational Efficiency white paper.

How to troubleshoot plasma cut quality

Like any cutting process, there are a lot of variables that affect plasma cut quality. Some of these variables include:

- Torch Type
- Torch Alignment
- Condition of consumables
- Arc Voltage, or cutting height

...and more.

Most of these variables are interdependent, meaning that if you change one variable, it will affect the others. Figuring out how to fix cut quality issues can be difficult, so the following information was assembled to provide the usual solutions to some typical cut quality problems.

Read the entire ESAB Plasma Cutting white paper.

How to select a gas supply system for a thermal cutting machine?

Selecting the best type of gas supply system for a CNC shape cutting machine will depend primarily on how much gas you will use, but there are some other factors that might affect your decision also.

Topics covered:
Cylinders, Liquid Tanks, or Bulk Tanks?
Gas Consumption
Advantages & Disadvantages of High Pressure Cylinders, Portable Liquid Tanks, and Bulk Cryogenic Systems

Read the entire ESAB Cutting Systems white paper.

Guidelines for Making Informed Stainless and High Temperature Alloy Purchases

Metals and Alloys that contain the element Nickel present a real challenge for today’s buyer.  The volatility of element pricing creates large and rapid fluctuations in pricing – therefore the decision to make or delay a metal purchase can have significant impact on finished product costs.  A few simple tips can help savvy buyers and purchasing agents better time purchases to achieve the best pricing.

Read the entire UPMET - Guidelines for Making Informed Stainless and High Temperature Alloy Purchases white paper.

Filtering Grinder Coolant Leads to Better Blades

Whether a knife maker is creating a high-end chef’s knife that retails for hundreds of dollars or a discount pocketknife, the manufacturer needs machine tools to grind the blade into a fine edge. The grinding process, however, creates swarf -- or flecks of metal -- that compromise the operation of machinery and the treatment of fluids used. Also, the coolant can help maintain optimum machining temperature during the grinding process. Exposure to high heat would undo the tempering process that makes steel less brittle.

Knife makers need to be mindful of the grinding process because it represents an opportunity to better manage costs, improve productivity and mitigate manufacturing’s environmental impact. Losma creates industrial air and fluid filtration systems, which are intrinsic to operating manufacturing equipment under ideal conditions. As robotics, lasers and precision instruments guide manufacturing, it is paramount to have the equipment operating at its peak. In the case of grinding knives, it means keeping the equipment cool and clean. Under these circumstances, the grinders require lower levels of maintenance and the knives produced have fewer defects. Grinders require a system to collect swarf consisting of a filter made with non-disposable or disposable type media and possibly a magnetic separator pre-filter to maintain the purity of the coolant and keep machines from overheating. Without the filters, lubricating and cooling liquids would need to be replaced, leading to higher material and waste disposal costs. Manufacturers also must consider the efficient use of space, since inefficient coolant set-ups can curtail the number of grinders available to work.

Read the entire Losma - Filtering Grinder Coolant Leads to Better Blades.

Back in the early 2000s the metals industry faced oversupply, plummeting prices and a wave of consolidation. Once-mighty companies such as the now-defunct Bethlehem Steel saw their credit ratings decline and failed to meet covenants on their cash-flow credit facilities. A sea change in financing tactics ensued. Lenders and metals companies turned away from cash-flow credit facilities to asset-based lending (ABL) because ABL offered the companies the flexibility and liquidity necessary to compete in a highly cyclical, global marketplace.

To illustrate why cash-flow loans fell out of favor, consider the business model of service centers, which act as distributors. They hold inventory for a short period of time, approximately 30 to 90 days. In a rising price environment their margins will improve, but in a falling price environment those margins may contract and perhaps turn negative. As a result, a company with a cash-flow facility that has financial covenants could quickly find itself in default if commodity prices tumble and cash flows drop.

Today, ABL is the predominant way companies in the metals industry finance their working capital. With ABL, the amount of credit extended by lenders is based on the liquidation value of the assets owned by the business. Asset-based revolvers help companies to bridge the gap between the cash flow they eventually will receive from sales and the amount of their current expenses. Download the White Paper >

To learn more about GE Capital, Corporate Finance, click here.