Behind the Wheel is a blog created by Stellana for the wheel industry. Whether you are new to polyurethane wheels or have been in the business for a long time, this blog is a great tool for polyurethane education, industry safety, company news and updates, and much more.
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Quality | Understanding & Reducing Hysteresis
Understanding and Reducing Failures:
Polyurethane is one of the most versatile materials.1 Physical properties can be adapted to solve challenging problems. Polyurethane
is formed by reacting a polyol (ether-based or ester based) with an isocyanate
(an MDI or TDI). It is then cured at a specific temperature for the optimal
time to reach desired physical properties. Properties are altered based on the
polyol and isocyanate and the application impacts the function. It is critical
to choose the ideal material based on the application and the conditions the
product is expected to withstand.
What is Hysteresis?
Hysteresis is a time-based dependence that relies on present and past inputs. Polyurethane is an excellent insulator and absorbs and stores energy,
which will then be converted to heat. If heat generation is greater than heat dissipation,
the polyurethane will melt internally, resulting in a buildup in pressure as
the material expands. The increase in temperature will change the physical
properties of the material. Evidence of
hysteresis can be indicated with a powder like substance, bumps on the tire, or
visible molten material. The most common causes of hysteresis are overloading
the part or operating at too great a speed.
Contributing factors to heat buildup in tires include: poor
conductivity of polymers, tread thickness, size of tire, speed of rotation,
load on tire, TIR of tire, and length of run. Improper installation- metal hub
rubbing on other metal object causing friction will generate heat.
Metal objects imbedded in the tire promote heat generation.
In the picture, a metal object is imbedded in the tire. The metal will absorb heat and raise the temperature of the wheel. As a result, the material changed physical properties and burned off the adhesive.
Hysteresis is commonly mistaken for bond failure. What is Bond Failure?
Bond failure is a result of improper surface preparation,
contamination, or machine malfunction. A true bond failure will leave adhesive
intact on the metal. The excessive heat generation in the hysteresis process will burn off adhesive on the poly or metals, or both.
Ways to Avoid Hysteresis
You can significantly reduce costs associated with downtime
and extend the life of your product with the proper conditions of the
application. Decrease speed of trucks, load capacity, or length of runs. Experts
will help you choose the correct system based on the application needs. Engineering experts will review
the design of the tire and optimize the cross-sectional thickness, runout, and
By now, we are all aware there is a PPE shortage for many of
the workers who need protective equipment the most. One of the most talked-about
items are masks.
We are also hearing how many companies are experiencing an
extreme decline in business. A local company, PFI Fashions Inc., took what
could be a negative situation and used their open capacity to make a very
positive impact on their local community. Jodie and Billy Joe Todd, owners of PFI, took it upon themselves
to begin manufacturing masks for those in need. Located in Genoa City, WI the full-service company specializes in screen printing, promotional products, and embroidery.
Within the course of a week,
they have completely shifted their production focus to making washable, cotton
face masks. They have been generously donating them to Aurora Hospital, local
EMTs, and the other essential workers who need them the most.
Because of their hard work, we were able to purchase masks
to keep our employees safer at Stellana. We want…
Customer – IAM Robotics IAM Robotics, creators of the world’s first autonomous mobile
manipulation robot, has found a niche in e-commerce order fulfillment. Its
robots use highly advanced computer vision and perception technology combined
with an articulated robot arm on a mobile base to autonomously navigate
warehouse aisles, picking and transporting products just like a human. Our Task
IAM Robotics turned to us for our polyurethane expertise.
The company tasked us with the job of providing a wheel material suitable for the
typical usage and environments of their mobile picking robots, named SwiftTM.
The company designs their robots to work
around the clock, continuously moving on the floors of warehouses and
distribution centers. Its charging system only requires a 30-second change
about once a shift, avoiding any lengthy downtime. The continuous operation made
localization a key consideration when selecting wheels for the Swift robots. The Swift™ Robot Swift works like a
human order pi…
How many days a week do packages
arrive at your household? For some of us, you could even ask how many times a
day do packages arrive at your house? Buying habits and expectations have been changing
for some time now, and these trends are forcing warehousing and manufacturing
operations to adapt. There is little to no room for downtime, and forklift wheels
and tires play a crucial role in keeping things moving during the seasonal
peaks and shopping holidays such as Cyber Monday. Current Climate in the World of
Ecommerce trends are making order
fulfillment more complex. In general, consumers are placing smaller orders more
frequently. With the ease of online ordering, it is not unusual that someone
places an order, then a few hours later, places another order with an additional
item they forgot. With a just few clicks, a passing thought can become a
purchase. Seamless operations provide the ultimate convenience for the purchaser,
but behind the scenes with each order, invento…