Message From The CEO
Welcome to our Fall 2013 Newsletter! We are coming into a wonderful time of year here in New England. The colors are becoming extremely vibrant and so is our team here at Jenike & Johanson. We continue to hire an amazing array of talent across all of our locations, we have opened our new office in Houston, Texas which is fully operational, and our structural design capabilities are taking center stage of late as we take on several new projects solving bulk solids storage structural failures. We develop new structural designs with unique hopper geometries and conduct inspections and analysis to determine why structures that are inadequately designed have failed. You will see an example of one of our projects below, and why it’s wise to treat silos with respect. Speaking of respect, we are also introducing two of our star performers here at Jenike representing our testing facility in our Tyngsboro, Massachusetts headquarters, and our engineering team in San Luis Obispo, California. We hope you enjoy learning more about our first-rate team, our global reach, and our structural engineering group. To discuss any particular application, please contact any one of our offices around the globe.
Fly Ash Silo Failure: Why Did the Collapse Happen?
A new bolted steel silo storing 9,000 tons of fly ash from the adjacent coal fired power generation station split apart two weeks after it was first filled to capacity. Up to this point, no ash had ever been discharged. Curiously, the silo collapse occurred at night when the silo was being neither filled nor emptied. During the investigation into this failure, calculations showed that the silo was under-designed and did not identify or account for a phenomenon called “Thermal Ratcheting”. The walls of outdoor metal silos expand during the day and contract at night as the temperature drops. If there is no discharge taking place and the material inside the silo is free flowing, it will settle as the silo expands.
Behind the Scenes at J&J
Jim Buckland, Lab Technician in our Tyngsboro, Massachusetts office, first worked at J&J back in 2008 as a Lab Assistant. This was his first job working in a lab environment, and he was here for 2 years gaining experience in the field. Over the years his path led him back to J&J where he is now a Lab Technician.
Brian Reel, a project engineer in our San Luis Obispo, California office since early 2012, also worked with Jenike & Johanson as a designer from 2003 to 2005 while he was pursuing his Bachelors degree in Aerospace Engineering from the California Polytechnic State University, San Luis Obispo. Brian continued on to attain his Masters Degree in Aerospace Engineering with an emphasis in control systems in 2009.
Jenike Blog of the Month
by Jesús Chávez Sagarnaga
I am on vacation in México at the moment enjoying family and the nice weather. Certainly, my vacations do not relate to storage structures but they do make me think about all the emerging economies in the world, such as México, in addition to the well-established ones, like the U.S. They all have industrial facilities (e.g. chemical, power generation, mining, cement production, plastics) that require rehabilitation and modifications to keep up with the demand due to the global population growth.
The obvious solution to meet the increasing global demand is to build new industrial facilities; however, new construction can be quite costly for plant owners. Another solution is to rehabilitate and modify such facilities.
Powder and Bulk Engineering Magazine – Treat Silos With Respect
Last October, the New York Times featured an article titled, “Silos loom as death traps on American farms.” They noted that at least 26 deaths caused by entrapment in farm grain bins were recorded in 2010. This past March, National Public Radio ran a “Buried in grain” series, which revealed that, while at least 300 deaths have occurred in farm silos over the past 30 years, serious weaknesses in worker safety laws and enforcement still abound.
Although the focus of these two pieces was on farm silos, the problem is far more widespread. Workers in industrial facilities of all types experience serious injuries and sometimes death when they walk on the top surface of material in a bin or silo, or when material falls on them as they try to clear an arch or built-up material from below. Another critical problem is asphyxiation, which is caused by “silo gas” in farm silos and by lack of oxygen in industrial silos.
October 15, 2013 Bloomington, Minnesota
Bulk Material Flow Fundamentals & Step-by-Step Bin Design Process
Fundamentals of Powder Blending, Sampling, and Post-Mixing Segregation
November 7, 2013 San Luis Obispo, California
One Day at J&J – A Flow Fundamentals Workshop
November 7, 2013 State College, Pennsylvania
Impact on Product Quality by Hopper Design and Conveying System
November 12, 2013 Webinar
Powder Blending, Sampling, and Avoiding Segregation