Barnum R.,Jenike and Johanson Inc.
Glass International | Year: 2014
The article explores some of the underlying issues of furnace feed bins and suggests features that should be considered during their design. The specific characteristics of a material that affect flow, which can be measured, are known as flow properties. Requirements for achieving mass flow during bin discharge include sizing the outlet large enough to prevent an arch from forming and ensuring the converging hopper walls are steep and smooth enough to promote flow along them. The flow performance of a furnace feed bin can substantially impact its effectiveness as surge capacity and ultimately product quality. Source
Carson J.W.,Jenike and Johanson Inc.
Practice Periodical on Structural Design and Construction | Year: 2015
Numerous codes and standards specify means to calculate material-induced loads that are needed to design silos. The three most commonly used of such codes do not provide users with consistent information, and many common silo design conditions are not covered. A brief description of each code and its limitations is provided, and common design conditions not covered by any code are identified. © 2014 American Society of Civil Engineers. Source
Barnum R.,Jenike and Johanson Inc.
Glass International | Year: 2012
Roger Barnum explains how new batch handling systems can be designed to prevent problems with the use of material flow property data in a glass manufacturing factory. The flow performance of a batching and furnace feed system can have a significant effect on glass quality and plant reliability. Once mixed, the batch material is conveyed and elevated to a surge bin. In the float process, these bins tend to be short in the direction of furnace feed and wide, generally covering the full width of the furnace. Consistency of the batch material is critical for producing high quality glass. Variations can result in changes of glass density, which can lead to areas of weakness, as well as visible defects such as seeds, blisters and stones. Sifting segregation can also occur when an active flow channel forms within a bed of stagnant material. This is referred to as a funnel flow pattern, and is common in storage silos, surge hoppers and feed bins. Source
Maynard E.,Jenike and Johanson Inc.
Chemical Engineering Progress | Year: 2010
Several approaches need to be employed to address pneumatic conveying problems and to significantly increase efficiency and reliability of pneumatic conveying systems. The first step in troubleshooting conveying problems is to gather data regarding pressure, temperature, feeder speed, and gas flowrate under startup and steady-state conveying conditions. The hopper is to be modified to promote a mass-flow discharge pattern, whereby all of the material is in motion during discharge, will produce a uniform discharge with a consistent bulk density. Mass flow can be achieved by changing the hopper geometry to give it a steeper angle, or by providing a smoother interior or both. The maximum flowrate in a dilute-phase line can be achieved by using the least amount of air required to achieve the minimum conveying velocities necessary to entrain the solids and prevent saltation. The leakage within a vacuum system should be corrected promptly to avoid pneumatic conveying problems. Source
Prescott J.K.,Jenike and Johanson Inc. |
Garcia T.P.,Pfizer |
Brown W.,USP Pharmaceutical Dosage Forms Expert Committee
Pharmaceutical Engineering | Year: 2014
This article presents a summary of the stratified sampling session held at the 2013 ISPE Annual Meeting. Source