Location and Dates:

April 12-14, 2016 – Simsbury, Connecticut (CT)
May 10-12, 2016 – Los Angeles, California (CA)
October 11-13, 2016 – Spartanburg, South Carolina (SC)
November 15-17, 2016 – Simsbury, Connecticut (CT)

Our high-powered, 3-day programs cover all the essentials for successful brazing of commercial and aerospace components.  The improvements to brazing operations that have resulted from these seminars have paid for the cost of the seminar many times over at many companies!

Notify your associates, your suppliers, your customers……anyone who needs to understand brazing!  You and they both benefit!  CLICK HERE for more information!

As mentioned in last month’s article, there are many suppliers of brazing paste out there, many of whom will put their brazing-paste into small tubular cartridges from which the paste can be easily and quickly dispensed onto components that are to be brazed. As shown in Figure 1, proper dispensing of paste from a cartridge begins with an electronically-controlled source of pressurized air (which can be adjusted over a wide range), and may also contain optional timing mechanisms. All of this can be contained in a simple table-top unit, such as the one shown, but which also comes in different shapes and sizes, and with other options.

The air hose coming from the dispensing unit should have a connector that is able to attach to, and lock onto, the back end of the paste-cartridge in a leak-tight fashion, thus allowing the high-pressure air to push the piston in the paste-cartridge forward. The dispensing unit may also have digital or analog meters on their face to show what the air pressure is in the hose, and it may also contain controls to allow the operator to vary dispensing time (which could vary from a small fraction of a second all the way to continuous-flow) if it is desirable to automate, or semi-automate the paste dispensing process. by Dan Kay

We study vacuum science and vacuum engineering in order to better understand the role vacuum technology plays in creating useful engineered products (Fig. 1, Table 1). Manufacturing as we know it, and research and development as we have come to depend upon it, would not exist without the creation and control of the vacuum “atmosphere”.. 

Vacuum techniques are important in both the industrial setting and for the scientific community, whether it be in heat treatment or high-energy physics. At the heart of vacuum processing for manufacturing is the modern vacuum furnace. Ever since the introduction of the electric light at the beginning of the 20th century, society and manufacturing have been linked to advances in vacuum science and engineering. Examples include the development of modern computers to advanced transportation systems; the very fabric of modern society depends on vacuum technology. By Dan Herring 

Burlington, Ontario, March 23, 2016 – VAC AERO has recently received an order for a complete all-metal hot zone refurbishment for a customer in Canada, in the Aerospace Heat Treatment sector. The retrofit work is for a horizontal furnace. The hot zone feature unitized construction for easy removal and maintenance. The lightweight design’s low thermal mass enables faster quenching and longer life. The heat shield package consists of one layer of .020” thick lanthanted molybdenum (Mola) sheet backed by one layer of .010” thick molybdenum sheet, and three layers of .014” stainless steel sheet. The heat shield package is supported by a 14 gauge stainless steel assembly that also acts as a manifold to distribute the quenching gas uniformly throughout the workload. Built for rugged usage and low maintenance VAC AERO hot zones feature unitized construction for easy removal and maintenance.

Every industrial vacuum furnace system uses a primary (aka mechanical) pump, which is also commonly referred to as a “backing” pump when either used in series with a booster pump, or used with both a booster and secondary (“high vacuum”) pump combination, such as a diffusion pump. These primary pumps are further divided into “wet” pumps (e.g., oil sealed rotary vane style or liquid ring pumps) or “dry” pumps (e.g., claw, hook or screw). Of the dry primary pumps, the most common types are the claw pump and the screw pump. 

Dry pumps are being increasing popular as an alternative to oil sealed rotary vane pumps for many medium and high vacuum applications (e.g., in low-pressure vacuum carburizing where fine granular soot is carried from the process into the pump). Designers and users of vacuum furnaces must have a good understanding of how claw and screw pumps operate. This includes the principles of operation, pump design, sealing, operating characteristics, features, purging, and ancillary devices. By Dan Herring

Last time we focused on the principles of operation of oil sealed rotary vane pumps including basic pump design, and pump oil. We now continue that discussion focusing on operational features and the inner workings of these pumps. 

Single Stage vs Two Stage Pumps. One of the limiting factors of a rotary vane pump is the Duo Seal, which is the oil filled non-contact seal in the small 0.025 mm (0.001”) space between the rotor and the stator at the top of the pump. In a single stage rotary vane pump, the pressure difference across the seal can approach 100,000:1 (1000 mbar vs. .01 mbar). Above this, the duo seal will start to leak oil from the high-pressure side to the low-pressure side (Fig. 1). This creates backstreaming, that is, the movement of pumping oil back into the vacuum furnace chamber. By Dan Herring

Vacuum furnaces are available in numerous styles and sizes and come in both standard and custom configurations. They are designed to process an almost limitless number of both semi-finished component parts as well as raw materials using a diverse set of thermal processes in equipment available from a wide variety of different equipment manufacturers located around the world.

The intent here is to provide a brief overview of some of the more common designs and applications found throughout the heat-treatment industry. The hope is that the reader will come away with an understanding that there is a vacuum furnace solution to virtually any design, application or specification encountered.. By Dan Herring

What kind of dispensing-tip should be used for brazing-paste cartridges?.

There are many suppliers of brazing paste out there, and many of them will put that paste into small tubular cartridges for you, from which that paste can be easily and quickly dispensed onto components that are about to be brazed. BUT, the choice of the actual type of cartridge-tip that you will use to extrude that brazing-paste from the cartridge is YOUR decision, NOT the decision of the paste-supplier, your customer, or some industry “tradition” you may be heard about, or perhaps observed being used at some brazing shop. by Dan Kay

The role of materials science (Fig. 1) is to study, develop, design, and perform processes that transform raw materials into useful engineering products intended to improve the quality of our lives. It is said by many that material science is the foundation upon which today’s technology is based and that real-world applications would not be possible without the materials scientist. The discipline has expanded to encompass materials for many highly specialized product applications.

The industrial revolution thrust metals into the forefront of technology, and they have stayed there ever since becoming the very foundation on which our modern society is built. One cannot envision a life where our transportation and communications systems, buildings and infrastructure, industrial machines and tools, and safety/convenience devices that are not an integral part of our daily lives. By Dan Herring 

Failures in metallic components may be caused by any of the following factors or combinations of factors: Design shortcomings, imperfections due to faulty processing or fabrication, overloading and other service abuses, improper maintenance and repair and environmental factors.

Not all failures are catastrophic. Many failures involve a gradual degradation of properties or excessive deformation or wear until the component is no longer functional. Failures due to wear or general corrosive attack usually are not spectacular failures, but account for tremendous material losses and downtime every year. Of course, early failures of the spectacular catastrophic order capture the most attention-and rightly so. Nevertheless, all failures deserve the attention of the investigator because they reduce production efficiency, waste critical materials, and increase costs. In some instances, they cause considerable damage or personal injury. Finally, failures can result in costly litigations. By George Vander Voort