Introducing Roll Shop Bonnets

A roll shop in an Indiana mill has coined these Bonnets. They have been using these parts for over 10 years and now have completely replaced all of their metal bonnets with polyurethane.

Roll Shop Bonnet Benefits:

  • Self-sealing polyurethane eliminates the need for a rubber gasket.
  • The polyurethane is resilient and holds its shape in the event of an impact during loading/unloading of the roll package into the mill. The dented and bent steel bonnets are a thing of the past.
  • Polyurethane is 70% lighter than steel. The mill has eliminated the use of a jib crane to bolt the polyurethane ones into place.
  • Due to the non-stick aspect of polyurethane, there is significantly less effort required removing the excess grease from the I.D.

What does a dead blow hammer have to do with success at a Tube Mill?

Heavy duty polyurethane Dead Blow HammerAccording to Wikipedia “A dead blow hammer is a specialized mallet helpful in minimizing damage to the struck surface and in limiting peak striking force, with minimal elastic rebound from the struck surface.”


So here is the STORY…
A tube mill’s high performance automated systems are designed to keep things moving, however, one tube mill had an issue with their pipe bouncing back too far when they impacted their adjustable pipe stop bumpers. The bumpers were designed to stop the tube and prepare them to be fed into the next area of the line.

The bouncing of tubes was causing misalignment and jams. The line then had to be shut down until the jam could be cleared. This was a continuous issue so the mill staff assumed that the hardness of the bumper needed to be adjusted, however, that was not the solution. The problem was so severe that the bumpers were causing a bounce back as far as 18 to 24” on large pipes and 8 to 12” on smaller pipes.

Fortunately, the mill contacted a representative from Kastalon to get a second opinion. Kastalon’s expertise in chemical engineering was able to determine that the hardness was not the issue, the physical and mechanical properties of the polyurethane bumper needed to be adjusted to allow the bumpers to absorb the energy rather than rebounding it. What they needed was a “dead blow bumper”.

polyurethane dead blow bumperOnce the bumpers were replaced by a proprietary Kastalon polyurethane bumper, the results were immediate and dramatic. The bounce of large pipes was reduced to 4-5 inches and the small pipes were only bouncing back about an inch.

Regardless where polyurethane is used, the secret is not just the hardness of the material, but how the material needs to work to its optimal performance in that application and environment. This is where Kastalon’s “engineered to fit” philosophy puts the emphasis on the desired result and the environment that a part is operating in. Even if it is a simple bumper!

Field of Springs

In the same city where Astroturf made its debut, another material technology Wrings Houston a new baseball marvel.

When the Houston Astrodome, baseball’s first indoor stadium, opened in 1965, it had a natural grass field. The grass required a translucent roof, which produced glare and caused fielders to lose track of fly balls. To solve the problem, the stadium’s roof was painted and the grass replaced with the newly invented artificial surface that we now call Astroturf.

No matter what you think about baseball on artificial turf, it is commonly agreed that Houston was at the forefront of baseball stadium innovation in the ’60s. It continues that tradition today. The Astros still play ball under a roof but only when necessary. That’s because the city erected Enron Field, a stadium with a retractable roof that makes natural grass possible. Although Enron Field is not the first stadium with a retractable roof, it does boast a special suspension system that is engineered to open and close the roof without glitches.

Bart Riberich, vice president of engineering at Uni- Systems, the Minneapolis-based firm that designed the roof travel mechanism, says that operating problems occur when the suspension system relies on bogies. They concentrate the load at a single point when the wheels hit a high spot on the rail, thereby thwarting smooth movement. Instead of bogies, Uni-Systems engineers turned to independent suspensions for each of the 142 wheels that carry the three huge roof sections atop Enron Field. To make the independent suspensions work, the engineers needed a suspension spring that would compress when the wheels met a high spot on the rail.

Finding the materials to make the springs was about as easy as hitting a Randy Johnson fastball. Almost from the start, Uni-Systems eliminated conventional metal springs because they couldn’t achieve the targeted 25-year lifespan. The designers turned their attention to elastomers, which are not only highly resilient and durable but also able to handle heavy load capacity.

The Uni-Systems design team, along with engineers at Kastalon Polyurethane Products, Uni-Systems’ partner on the project, selected Adiprene urethane prepolymer from Uniroyal Chemical to make the springs. “The springs had to be compact to make the design work,” says Bruce DeMent, president of Kastalon. “The versatility of Adiprene urethanes allowed us to compound an elastomer that would give us the required performance.”

The patented cylindrical springs installed at Enron Field consist of alternating layers of steel and urethane around a central shaft. Only 8 in. in diameter and 9 in. tall, the assemblies support a normal load of 125,000 lbs and peak loads up to 325,000 lbs. Now, the Astros can play ball come rain or shine.

More information on polyurethanes is available by contacting Kastalon Inc. , 4100 W. 124th Place, Alsip, IL 60803 or calling (708) 389-2210.

Polyurethane Is A Perfect Fit For Pipe And Bar Straighteners

Pipe and bar straighteners are a great market for polyurethane parts for noise suppression, product protection and conveying. Kastalon has supplied this market place with many parts on an MRO basis. We have developed a material that has the impact resistance, cushioning and enhanced wear resistance required to provide the optimum in life for a trough liner.

We would recommend using material thicker than 3/4″, generally 1-1/4″ to 2″ thicknesses is ideal. The liner will function properly until it is worn through. Some additional positions that could and should be polyurethane/plastic covered are:

  • Protective Pads: (shock absorption, noise suppression, cut, tear and abrasion resistance, product protection)
  • Kicker shoes (these are the arms that pick up and push or kick the tube/pipe/bar, down the ramps).
  • Transfer arm covers (similar or the same as kicker arms, they also may be a wheel moving the pipe from one conveyor to the other)
  • Any hard stop surfaces for the pipe
  • V Rollers for roller transport (better friction and drive than plastic)

Kastalon produces a highly engineered a polyurethane compound in 75 Shore D hardness that is extremely effective in protecting the pipe surface and has a very long life. We find these straighteners mostly in solid bar plants where shafting and forging stock have very critical surface finish requirements (to prevent stress points in the surface of the bar which lead to cracks)

Any where there is shock, polyurethane due to its elastomeric nature, including in plastic hardness, is more effective and long lived than plastic.

Follow the Money – A Mandrel Sleeve’s Truth

When my children and I are talking about various social, political or other issues, I often find myself using the phrase “FOLLOW THE MONEY”.  It’s funny how often this simple phrase holds true. Many answers to some of life’s question can be answered by this phrase.

Why should mandrel sleeve’s be any different? An example of this hit me in the head when I was talking with a steel producer in New Carlisle, IN. They didn’t think that they had any issues with the life of their mandrel sleeves. They shared with me that they consistently got about 8 months to a year of life on their sleeves and then the sleeve needed to be replaced due what they called “sagging, like it had no rebound or memory”. The plant manager said “It’s been that way as long as I have been here, I don’t feel we currently have any issue’s with the life of our Mandrel Sleeves”. So I asked can we “Follow the Money”?

Because they kept such detailed records on the longevity of their sleeves, it would be that kind of record keeping that would allow us to “Follow the Money” and prove to them that they should and could get a longer life span and more efficiency out of these sleeves.

So we offered the “Kastalon Challenge” – Provide us with all of the specifications, including the application and environment the mandrel sleeve will be operating in. Purchase and run the engineered Kastalon Mandrel Sleeve and if it does not last longer than your current supplier’s Mandrel Sleeve, we will supply them with another mandrel sleeve for no additional cost.

Kastalon manufactured a mandrel sleeve for their high speed steel processing line. At the rewind end of their line they have two rewind mandrels that work in tandem with each other. This would make for a great test. They installed the Kastalon sleeve and their current supplier’s sleeve as well at the same time. After the sleeves were tested for only four months it was clear on inspection some “sagging” was already showing on the current supplier’s sleeve, however, the Kastalon sleeves showed no wear or sagging whatsoever. So “ Follow the Money”. It was clear that Kastalon sleeves did in fact last longer and their assumption that they had no issue with their current supplier sleeves was not adding any profits (MONEY) to the bottom line.

They placed an order for two more Kastalon sleeves giving them a total of three. A year later they ordered one more from Kastalon. This gave them two in use and two spares that they would rotate in and out of production every six months for inspection.

A year later they placed an order for two more sleeves just as a precaution because they have never experienced mandrel sleeves that would last that long. As of today, all four of the original sleeves are still in rotation and the two ordered a year later are still in the storage warehouse yet to be used.

This is a high speed line that usually runs around 2,800 feet per minute. This customer has averaged running at around 78 percent of capacity. You can imagine the amount of times our four sleeves have expanded and collapsed in the past 5 years.  And to think they thought they did not have any issues with their mandrel longevity. I am so glad that we “FOLLOWED THE MONEY”

Mining uncovers polyurethane advantages

One of the by-products of mining involves displacing huge amounts of dirt so it only seems natural that the type of equipment that is used is coined “earth movers”. Equally as logical is the fact that the OEM’s for these types of equipment must consider certain protection from the abrasive nature of dirt and vibration. For many years, Kastalon has engineered a proprietary polyurethane formula specifically for these types of applications.

Recently, a new mining challenge was given to the Kastalon designers for their problem solving. When reeling in a 4″ diameter steel cable, protection was needed to prevent the cable from banging into the steel structure of the equipment. Historically, wood blocks had been used to shield the cable from damage. The downside was that the wood splintered and broke easily. This created a housekeeping mess which required additional labor to clean-up and replace the blocks. If the operators did not take the time for the necessary maintenance, the steel cable would get damaged from banging into the steel structure which shortened the life of the cable.

Using the same proprietary Kastalon Polyurethane® formula used for other mining applications, the designers presented an engineered polyurethane pad that had a much longer life than the wood blocks it was replacing. In fact, the first set lasted over two years, which was unprecedented. The other advantage was that when the pads did need to be replaced, they were easily replaceable.

To learn more about Kastalon mining solutions or to contact a designer for a project that needs improvement, contact Lyn at sales@kastalon.com.

Polyurethane improves safety in mills

In a steel or aluminum mills, safety is always a major concern. With many employees staying in the workforce longer, there is a growing concern for reducing injuries that result from heavy lifting.

Recently, an aluminum mill established a goal to limit the maximum weight lifted manually at 50 pounds. In the roll shop this was a major concern because the bearings are held in place by a large steel split ring, known as a thrust collar that is locked into place. The maintenance process of changing out the bearing requires the worker to break the ring free and remove it. These rings can typically weigh more than 60 pounds each.

Interestingly, Kastalon was able to design a custom engineered polyurethane alternative that had all of the same strength and wear characteristics of the steel ring, but only weighed 12 pounds.

The first 4 rings well exceeded the life expectancy by lasting more than a year in continuous service and proved to reduced lost time due to back injuries in that area.

Not only did the mill find a method that would protect their workforce from unsafe practices but also found a way to achieve greater efficiency.

If you would like to learn more about our metal processing solutions, contact Lyn Thorne at lyn@kastalon.com.