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The Value of Lessons Learned; Paying the Information Forward

Lessons Learned Word Cloud

Everyone in industry talks about “lessons learned” and are quick to remind each other of the importance of documenting those lessons and keeping them tucked away for the next go around. When the surface of the topic is scratched however, it becomes obvious in many cases that ‘lessons learned’ is a catchphrase with little meat on the bone. Answers to what these important lessons are, and how they are supposed to be documented is often fuzzy, and even more dubious is how these lessons will resurface when a similar situation presents itself again.

Let’s start by defining a “lesson learned” as any explainable situation in the course of a process or project that has an unanticipated (positive or negative) impact in the realization.

For example, when buying your first refrigerator, the importance of measuring the kitchen space is critical and obvious. However, measuring the door of your home to ensure you can bring the appliance into the kitchen may get forgotten in the excitement of shopping.

After pulling the front door off the hinges, disassembling part of the refrigerator or pondering multi-dimensional physics for an afternoon, it is unlikely the entry-way measurements will be left off in future shopping trips, and can be called a lesson learned.

The human mind will file away a lesson and store it for future recall, then with no apparent prompt, can bring that memory up when it is most relevant and needed again. Unfortunately, organizational memories are rarely so elegant or effective. It’s often left to the individuals in an organization to recall the things that go right or wrong in a given project and apply them to future projects. This approach can be effective in limited situations however it often leads to ‘tribal knowledge’ and serious brain-drain when an experienced long-time employee leaves the organization, dooming your team to repeat mistakes that have already been paid for. The typical answer to this issue is a Lessons Learned Database. This is usually executed as a simple one-level database that often devolves to a list of well-intentioned statements about projects. Sadly, documenting lessons learned does not equate to applying them.

To properly apply lessons learned, they must not only be documented but also retrievable at the relevant place and time, by anyone in the organization, without prior knowledge there is a lesson relevant to the circumstance. This isn’t a small order. Successful recall of lessons learned is most frequently found in organizations with the wisdom to pair a “Lessons Learned Database” with a risk assessment or project kick-off document. Quality document requirements like these will drive a group of decision makers to review a list of lessons, and with experience and clever sorting (or good memories) this may be all it takes to recall and apply lessons that will save the company both time and money.

In addition to the application of new project processes that require process review, there are a few emerging technological solutions that may also present opportunities. Since the arrival of Twitter, the use of ‘hashtags’ has grown in popularity. Don’t discredit them as tech-speak or assume their application is limited to use in social media. Many existing databases (including systems built on a SharePoint platform) can append tags to a database entry. This allows a company to tag any issue, discovery or resolution with #lessonlearned as well as other relevant qualifiers like #shipping or #precisionmachine.

These tags become searchable entries that can help to narrow and filter a broad pool of results down to a very concentrated return of relevant information about similar past undertakings. The use of tags can become a sort of institutional memory that completes the three-part cycle of learning a lesson, remembering it long enough to benefit and recalling it at the critical moment when it can be most beneficial.

We have moved past simple Lesson Learned Databases, these are an artifact of the past that was mostly fiction we sold ourselves encompassing a hope that we will magically remember the important things when the time comes.

Technology and some basic process steps can turn what may have been a meaningless list of observations about past projects into a relevant guide to prevent making the same mistake twice. The implementation of quality-processes and supporting technology like hashtags certainly has a learning curve and the cost is not always clear at the onset.  However, in nearly every circumstance, the cost to implement tagging will be lower than the alternative of making the same mistakes over and over or losing important knowledge along with an important employee.

Take the time to consider the value of implementing institutional knowledgebases that are achievable and effective; the cost/benefit is clear.

Contact Keller Technology today to learn more about possible solutions to your most challenging manufacturing problems.

When is a process a process?

process documentation on an ipad

The importance of not over-documenting or encumbering employees in the name of Quality.

With a growing drive for “quality systems” there is a lot of talk about ‘process’ in industry today. Ongoing discussions about how to define, optimize and document processes happen in every office and around every coffee machine. Accompanying these discussions is a near inevitability that many of these topics will quickly escalate from friendly chat to departmental clash. It begins innocently enough with best intentions when someone launches a conversation by suggesting a review of a process.

In short order, the conversation turns to the brass-tacks of documenting steps for the benefit of training and consistency. Then comes the moment of frustration when a complicated process step turns into a point of contention because someone believes it should be considered its own process or perhaps because there are too many options, inputs or other complicating factors. Discussion ensues and tensions rise as the complexity of the issue grows.

From here the conversations can sour quickly from frustration; devolving into questions like “Where does this all stop?” or “How far do we go with our documentation?”.  Cooler heads usually prevail, and before anything regrettable is said, the discussion is tabled for another time. Sadly, this pattern leads to a dark cloud hanging over the idea of process reviews and if left unchecked will create a culture of stagnation and stop critical progress dead in its’ tracks.

Though the dissenting questions can be dangerous, they are also very valid and ultimately some of the most important to real progress in process improvement. How deep should processes be defined? How far do you go with documentation? How do you not paint your workers into a corner with regimented documentation when the map doesn’t match the land? Everyone has a different perspective on these and in truth the answer to what is or isn’t a process will universally come down to the same thing every time “it depends”.

Lets’ take a moment to explore exactly what “it” depends on, and how we can use these questions to resolve issues instead of instigating conflict.

A safe place to begin looking at defining a process is by asking “can this be done correctly and consistently by a reasonably competent professional without reading instructions?”. In other words, can a person be expected to hold the full details of the job at hand in their head without reminders, cheat sheets, notes or prompting? If the answer is ‘yes’, then it is a task, not a process.

Changing a vehicle’s oil is a process, however pouring new oil into the engine isn’t a sub-process that requires detailed step-by-step instruction, it’s a task that any reasonably trained individual can properly complete without reminders or aids (we hope). The documentation can read “add oil” without going into the details of opening the container. A process-documents’ job is to identify the tasks, but that doesn’t mean the step-by-step instructions need to be spelled out for every single motion or activity. Avoid over-documenting tasks; it can save a lot of dickering over granular details, cuts back micromanagement, documentation and reduce a lot of process audit liabilities.

Another great method for identifying a process is counting steps.

There is some debate to be had here, and it will always be relative to considerations of risk; a process will have no less than ten steps and no more than twenty-five. The professional hair-splitters of the world will of course be quick to step forward and point out that any ‘step’ can be broken down into more steps. While this is technically true, the considered assumption of a “reasonably trained professional” helps to settle the issue. In the task mentioned above, “pour fresh oil into the engine” more than suffices, and a reasonable professional doesn’t need to be told to remove a cap, tilt the bottle, etc. Keep processes documentation short, a process with more than twenty-five or so steps can begin to feel unwieldy or intimidating and will likely prove difficult to train new staff on.

Most process improvement conversations begin with a discussion about a subject that is well over the twenty-five steps rule, don’t let this deter you! Break the discussion up into bite-sized pieces. Begin with broad strokes and work your way down, if you keep in mind the above guidelines you will find natural breaks in workflows that will allow a team to identify processes that meet the criteria of being complex enough to warrant documentation and simple enough to complete without a full manual. When these sweet-spots emerge, let them guide the documentation.

Process reviews will begin to move more smoothly with these simple tools, and the documentation will evolve naturally to lean and effective instructions that not only represent the work being done but become valuable points of reference to your front-line staff.

Keller Technology provides our customers with quality performance, value, schedule adherence, and technical compliance.

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SXR Undulator Installation at Lawrence Berkeley National Lab

Undulator Installation

Congratulations to the teams from SLAC National Accelerator Laboratory, Lawrence Berkeley National Lab on the successful installation of all 21 SXR undulators into the undulator hall. Keller Technology is proud to be a key supplier for both SXR and HXR undulators for the Linac Coherent Light Source-II (LCLS-II) project at SLAC.

Funded by the US Department of Energy, the LCLS project utilized SLAC’s existing linear accelerator’s electron beam and created the world’s first hard X-ray free-electron laser. The LCLS-II project adds a superconducting linear accelerator which will generate a nearly continuous x-ray beam. The use of superconducting accelerator technology for LCLS-II will provide for a major upgrade in capability, increasing the rep rate from 120 pulses per second to 1 million pulses per second. Along with the addition of a superconducting linac, LCLS-II will feature a new electron source, a cryogenic cooling plant for the superconducting linac and two new variable gap undulators.

The LCLS-II is poised to address the DOE’s grand challenges and provide groundbreaking scientific insights into understanding matter and energy at the electronic, atomic and molecular level.

Keller Technology was proud to be chosen as a key supplier of both SXR and HXR undulators for our expertise, personnel and capability to manage and execute the high-volume production of large but precise instruments. Our vertically integrated capabilities include technical welding, large envelope 5 axis machining, large format CMM metrology, both heavy and clean room electro-mechanical assembly integration and testing.

Find out more about how Keller’s team of skilled engineers can take your project to the next level.

Know Thyself: The Importance of Understanding Your Internal Quality System

Does your company have a quality system? Are you sure?

If you have an ISO certification like 9001 or a similar compliance standard offered by an organization like the Society of Automotive Engineers, you almost certainly have a Quality system in place. Even in the absence of those certificates, most successful companies have some sort of system, guidelines or best practices in place that relate to ‘quality’. Your company may have a well-functioning quality system and not even know it.

What is a quality system?

A quality system doesn’t have to be complicated (though they often get that way). At its root, a quality system is just a fancy way of describing a structured set of business practices, processes and facilities that have been put into place for meeting customer requirements and managing product quality related issues.

Some examples of quality system processes:

  • Provisions for accepting customer feedback
  • Return material authorization (RMA) process
  • Change tracking
  • Supplier management programs
  • A system of objective internal evaluations for production related processes.

Each of these is a unique quality related element and each is also a common inclusion for most businesses based on their operational needs. It’s unusual for any company to forego all types of quality management and maintain consistent operation for a meaningful period of time; these are just parts of how business is done. In most cases, the question shouldn’t be “Do you have a quality system?”, but rather “Is your quality system effective?”.

Understanding an organizations quality system is relatively simple

Begin by looking at how the company interacts with its customers, this is always a good measure. What policies are in place for accepting orders? Is there a reasonable return authorization system in place? Account managers and project managers are often empowered by quality driven principles to assist in communicating customer requirements and guiding change in a traceable way that ensures specifications remain in scope.

A robust quality system will also extend far beyond those fundamentals. The ability to internally evaluate performance, internal training and communication of failures in process or product are also key factors. Most critically however to every system is ‘leadership buy-in’. Without a committed management team who is willing and dedicated to owning up to mistakes and making choices to do the right thing for customers and staff, a quality system is reduced to little more than a sales pitch.

So if all (or most) companies have a quality system as part of the default design of operations, why should we care? What separates one quality system from another? Why is it important to understand your organizations system?

A quality system is a tremendous sales tool

When packaged and presented in an authentic way and backed by organizational leadership, a quality system becomes a commitment to squarely aligning your customers interest with your own. Every individual in an organization should be aware of their part in the bigger picture and how they contribute to the system. When every individual is represented in a system it is apparent to any outsider that the whole is greater than the sum of its parts. Leading with this kind of energy becomes a powerful signal to customers, and they will want to be a part of it. In addition, all levels of staff will feel more engaged and act as a team to support the organizations mission rather than just looking to their next paycheck.

Learning to appreciate and share your company’s quality system will allow you to better see the overarching philosophy of the company, provide interesting insights into leadership and culture, and when executed well, will help customers, staff and leadership feel like they are contributing to something larger and more important than themselves, not just transactional business.

A quality policy isn’t just a set of tasks, or some documentation. It certainly isn’t just a framed certificate on a wall. It is a commitment to growth and success for the company, its staff and their customers.

Our mission at Keller Technology is focused upon total reliability. We provide our customers with quality performance, value, schedule adherence and technical compliance.

Find out how we can help with your manufacturing needs.

Vacuum System Leak Detection

Leaks in a vacuum system can be defined as an undesired gas flow and may be proven to exist as well as pinpointed for repair by applying leak detection techniques. When assessing vacuum system performance, leaks can be a frustrating aspect of operations. There are several classes of leaks:

True leaks – cracks or holes allow gas flow into the system

Virtual leaks – trapped volumes of gas which are slowly released within the system

Outgassing – gas flow resulting from techniques or materials used within the system.

Through the application of leak detection techniques, true leaks can often be pinpointed and repaired to bring the system within the desired vacuum specification.

There are several methods and tools to detect leaks; the most common of which is reduced pressure testing with a helium leak detector.

Helium is an ideal tracer gas for use in leak testing, because its light, small molecules easily flow through the tiniest of leaks. Helium is chemically inert, non-toxic and non-reactive, so it will not adversely affect the system being tested or the operator conducting the test. It is highly sensitive to detectors, and allows for the vacuum system to be tested while in normal operating conditions. Helium leak detectors are composed of a pumping system equipped with a small mass spectrometer.

To conduct a basic leak test, the detector is connected to the vacuum system and helium is applied along the outside of the vessel at likely leak sites. If a leak exists, the helium will pass into the system and travel to the leak detector. The detector will measure the partial pressure of the helium, and display the results as a flow rate. Regular calibration with a reference leak is necessary to properly maintain the integrity of the helium leak detector results.

Leak Detector

Leak detection can be a time-consuming process requiring a great deal of patience, but there are a few best practices that can make leak detection faster and simpler to perform.

  • Whenever possible, design the vacuum system with a valve to allow connection of a leak detector without requiring venting of the system.
  • Prior to assembly, test individual components, especially those that will be inaccessible when the system is in operation to streamline troubleshooting efforts when performing future leak testing.
  • Flanges and gaskets are likely culprits for leaks, and should always be inspected for dust, debris and damage prior to installation.

Contact Keller Technology to learn more about possible solutions to your most challenging manufacturing problems.


Types of Vacuum Pumps

When designing your vacuum system, one of the most important choices you need to make is the type of pump(s) you’ll use.

When designing your vacuum system, you want a pump that will remove gas particles, not introduce contaminants, and not affect its surroundings by introducing stray electric or magnetic fields.

Ideally, pumps should be compact, easy and inexpensive to use and maintain, environmentally friendly and reliable. Some pumps can be used starting with the system at atmosphere, and some require a greatly reduced system pressure before they can operate. Depending on the pressure specification of your vacuum system, you may need to combine multiple pumps to achieve your desired vacuum level.

Pumps can be categorized in many ways, from the vacuum range they work best in, to the way they remove gases from the system.

Pumps can be characterized into two main classes: transfer and capture. Transfer can be further divided into displacement pumps (gas is mechanically separated and compressed with each pump stroke) and momentum transfer pumps (gas particles are driven out through the pump exhaust by high-speed vapor jets or rotor systems).

Examples of displacement pumps include rotary vane, liquid ring, claw and roots, while examples of momentum transfer are diffusion and turbomolecular pumps.

Capture systems trap gas particles and often have finite pumping capacity.

Examples of capture systems include sorption pumps, cryopumps, getter pumps and sputter-ion pumps.

Pumps are also categorized by their effective vacuum range. Rough pumps can be used from atmosphere and generally attain a system pressure of ~0.1 Pa. Examples include diaphragm pump, liquid ring pump, rotary piston or rotary vane pump, steam jet pump and sorption pump. Lower pressures can be attained by diffusion pump, turbomolecular pump, cryopump, and sputter-ion pump, however these cannot be used from atmosphere. For ultimate pressures below 0.1 Pa, a combination of pumps must be used.

The final classification we’ll discuss is wet vs dry. A wet pump is sealed by the presence of a liquid pump medium, and a dry pump is not. There’s always a risk of oil backflowing into the system and presenting contamination with wet pumps. However, depending on the application and sensitivity of your system this may not be a problem.

When selecting a pump, pay careful attention to the specifications provided by the manufacturer.

Manufacturers provide many specifications regarding the operating parameters of their pumps. While searching for the ideal pumps for your system, you may come across any/all of the following:

  • Throughput: the amount of gas which passes the inlet port of a pump per unit time (Pa*m3/s)
  • Pumping speed: volume of gas discharged per unit time (m3/s, l/s, or m3/hr)
  • Ultimate pressure: pressure at which equilibrium exists between pumped gas and back-flow, or the pressure at which the net pumping speed is zero (Pa)
  • Compression ratio: ratio of exhaust pressure and ultimate pressure (K0)
  • Gas type dependency: certain gases and vapors can be pumped better or worse by different types of pumps
  • Working range: pressure range where the pump manifests its optimum pumping speed

Keller Technology Corporation has decades of experience integrating all types of pumps in vacuum systems. Contact Keller Technology to learn more about possible solutions to your most challenging industrial equipment manufacturing problems.

Critical Infrastructure – The Care and Feeding of Suppliers

Ever have a supplier miss a deadline? Was it a big one? What did it cost you?

Supplier failures are an all-too-common fact of business, and as easy as it may be to villainize suppliers for failures, sometimes it is simply out of their control. Shipments stuck in customs, logistics hang-ups, and mis-entered purchase orders are just a few of the ways that suppliers can inadvertently throw a wrench in a production schedule. So the million-dollar-question is…what are you doing about it?

Critical Infrastructure can be defined as the collected networks, assets and systems necessary for the fundamental operations of an organization. If asked to list ‘critical infrastructure’, regardless of their sector, most companies would end up with a very similar top ten list.

Somewhere high on that list will likely be facilities, capital equipment and staff. These are all common elements that are necessary for daily operation. In every successful business, each of these components are represented with cautious planning and mitigation to support them against failure. Facilities and equipment receive preventative maintenance; and staff are provided with health benefits, flu-shots, and wellness programs.

Businesses take the time to protect their people and facilities because without them they are dead in the water. Managing suppliers is no different, they are as critical to an operation as the facility’s roof. The question then becomes how to best support vendors and the supply chain. Volumes could be written on how to best mentor small suppliers and strengthen relationships with larger suppliers.

Here are a few simple steps that are easy to implement and will help support your key vendors.

Know your suppliers

Learn your supply chain and maintain an up-to-date documented supplier list for every component used in your products. Once a list is established, track suppliers with performance metrics such as on time delivery and quality. Most importantly, provide the feedback to your suppliers. If a supplier doesn’t know when they fail, they can’t fix it. Metrics and reporting are a one-time headache to implement that will pay off in dividends down the road. Understanding supplier performance metrics provides the opportunity to leverage purchase-volume, delivery and quality as negotiating power. Most importantly, tracking suppliers for quality and on time delivery provides perspective on the value of your purchases and helps to quickly identify when it’s time to shop around for a better deal.

Develop relationships

With metrics and tracking in place, the next step is finding the right people in a supplier’s organization to get the feedback to. Suppliers often have Quality Managers as well as Account Reps who can advocate for customer interests. Take the time to invite key suppliers to tour your operation and to visit theirs. Developing relationships with suppliers draws back the curtain separating customer and vendor. In-person visits create discoverable moments and opportunities to learn about emerging products and services that could result in savings through consolidated purchasing. At the end of the day, when something goes wrong it’s easier to fix when there is an existing relationship. In a world of expanding international business suppliers, relationships can be tough to build but absolutely worth the effort. Begin by prioritizing suppliers with poor metrics, as well as sole-source providers. These are the most critical relationships.

Two is one, one is none

Redundancy is a cost risk that can become operationally challenging very fast. So is a last-minute supplier failure. Mitigating these risks means finding a balance. When delivery is critical, when success is the only option, there must be a contingency plan in place. If deadlines are tight, or a part is technically challenging, make sure there is a back-up plan in place to ensure success. Knowing several resources for a complex part or unique material may be necessary. Similarly, doubling ordering lead times may be appropriate to ensure time to reorder should Murphy’s Law make an appearance. Consider the worst-case scenarios and mitigate against them with deliberate, well-planned redundancy through smart supplier management.

Whether its staff, facilities or supply chains, protecting critical infrastructure can be as challenging as it is necessary. When working with suppliers, take the time to understand their capabilities, weaknesses, build strong professional relationships and help them grow. An investment of time with suppliers will show dividends in improved quality and on time delivery metrics in tangible ways to help protect against or minimize the impact of supplier failures. Supplier management is as important as annual roof inspections or employee health and morale. Help your suppliers and they will help you.

Contact KTC today to schedule a tour of our facility and build a relationship with us.

Vacuum System Pretreatment and Cleaning

Achieving the ultimate pressure of a vacuum system is greatly affected by the amount of gases or vapors contained within the system. To improve initial pumping efficiency following assembly or maintenance activities, outgassing can be reduced by properly pretreating the components within the system. The higher the ultimate pressure specification, the greater the need for cleanliness, however all systems will benefit from proper pretreatment.

Prep the physical surface

In vacuum systems, surface porosity is an excellent trap for gases and vapors. The first pretreatment step involves smoothing that surface to remove thick oxide layers such as rust or aluminum oxide. The most effective means of removing surface porosity is by mechanical grinding, brushing, or blasting with glass or ceramic beads.

Clean to reduce surface contaminants

Once the physical surface is prepared, the next step is to reduce hydrocarbon contamination from oils and coolants that may have been introduced via machining, contamination from pumps or improper handling.

  • Choose a soap or organic solvent that is compatible with the material
  • Decide if the cleaning agent needs to be at an elevated temperature to increase its chemical activity
  • Apply sufficient mechanical force (i.e. ultrasonic bath or high-pressure sprayer)
  • Determine how much time the component will need to be exposed to the cleaning solution (e.g. dipping will require more time than spraying)

Bake at the highest material-permitted temperature to remove adsorbed gases and vapors

After the surface contaminants have been removed and the cleaning agents thoroughly rinsed away, the final step in the pretreatment process is the bake-out. For components, this can often be conducted inside a vacuum furnace. Baking helps to remove water adsorption from the surface of the material. In general, the higher the furnace temperature, the faster the degassing.

Keep your system clean

  • Always protect opened vacuum systems from atmospheric and human contamination
  • Take care to choose packing materials that do not transfer oily substances to the vacuum components, such as aluminum foil or plastic sheets with a low outgassing rate
  • During assembly, consider environmental and human factors to avoid introducing outgassing contaminants into the system
    • Environmental considerations include factors such as humidity, dust particles, and oil mist/vapor
    • Human factors include special clothing to prevent contamination from fingerprints, dander, hair and perspiration, as well as using clean tools made of stainless steel or aluminum

Taking appropriate steps to prevent contamination will reduce the need for cleaning, and ultimately help to achieve the desired base pressure more efficiently.  Our dedicated engineering staff is well-versed in the proper manufacture of custom vacuum chambers, from assembly through final test and packaging protocol.

Contact Keller Technology today to find out more about our custom vacuum chamber solutions.

Selecting Materials for Vacuum Systems

Material selection is crucial in all aspects of a vacuum system. In a vacuum vessel, the walls must be strong enough to withstand the pressure difference of the system pressure and the external atmosphere. The vessel material must be able to be joined to other materials to create valves, flanges and feedthroughs. Still other materials must be used to create leak-tight seals at connection points for system components. 

In general, materials in a vacuum system need:

  • Wide temperature tolerance
  • Similar thermal expansion rates
  • Low outgassing rate

Other potentially desirable traits include:

  • High strength
  • Elasticity
  • Electrical conduction or insulation
  • Thermal conduction or insulation
  • Non-magnetic
  • Low volatility
  • Low chemical reactivity
  • Radiation resistance

In metals selection, machinability, leak-tightness of welded or brazed joints and corrosion resistance are important considerations. The pressure range is also a factor when selecting metals for vessel walls.

  • For ultra-high vacuum, the density and purity of melted and cast materials is highly useful, however it’s also relatively expensive.
  • In high-vacuum systems, drawn, rolled and pressed materials work well, but be aware they may exhibit leaks in the rolling direction.
  • Cast materials are cost-effective and suitable in fine and coarse vacuum systems.

Different Materials Used in Vacuum Systems

vacuum chamber materials

Stainless Steel

(Particularly 304 SST) widely used for vacuum vessels – high-strength, suitable for wide temperature changes, doesn’t easily oxidize and may be joined by welding or brazing.

Copper

(Particularly OFHC – oxygen-free, high conductivity) commonly used for gasket seals and feedthroughs – doesn’t outgas much, withstands wide temperature changes, excellent conductor of electricity and heat, may be joined by welding or brazing, relatively soft with few microscopic leak paths and may be nickel-plated to improve its chemical resistance.

Ceramics

Excellent insulator for electricity and heat, fragile but has great compressive strength, low thermal expansion rate and may be brazed to other materials in the system.

Kovar

Magnetic alloy composed of 54 percent iron, 29 percent nickel, and 17 percent cobalt – intermediate material used to join glass-to-metal or ceramic-to-metal through brazing. Coefficient of expansion is between that of ceramics and stainless steel and provides vacuum-tight seal between materials even in extreme temperatures.

Elastomers

Commonly used for gasket seals – flexible but not compressible, soft, high elasticity (and therefore reusable), permeability may make them unsuitable for UHV systems, generally permeable to helium, which can complicate leak testing. Specific examples:

  • Buna-N: synthetic rubber that’s inexpensive, resistant to helium, and useful in applications that are not heated about 80 C.
    • Viton: widely used for O-rings, valve seal, and gaskets in temperatures up to 150 C. Low outgassing makes it suitable for both high and ultrahigh vacuum systems.
    • Polyimide: a substitute for Viton in slightly higher temperature applications (up to 200 C). Requires more sealing pressure than other elastomers,] but is also more resistant to radiation. Absorbs water.
    • Silicone: Useful in vacuum furnace applications. Silicone compounds are able to withstand high temperatures but have poor outgassing rates and are permeable to helium and water.

Contact us today to discuss our custom vacuum chamber capabilities.

9 Main Processes Used for the Deburring and Finishing of Metal Parts

Deburring is the process of chamfering or rounding sharp corners formed on a metallic part during the machining process.  Deburring can also remove the raised edges and small pieces of material that may remain attached to a workpiece after it has been machined by a cutting tool or grinding wheel.  Finishing processes alter the surfaces of a workpiece to remove machining marks, scaling or pitting.  Finishing can also enhance the appearance or function of the part and prepare it for subsequent coating processes such as bonding, plating or painting.  Deburring and finishing are important process steps that should not be overlooked by the engineers and technicians designing and manufacturing component parts. 

polishing kit parts

Hand Grinding, Sanding, Lapping and Polishing

Manual processing of parts is still commonplace in today’s modern manufacturing facilities.  Many parts that are machined on sophisticated CNC equipment are still deburred and finished using an array of hand, ultrasonic and air powered tools.  Files, stones, knives, abrasive sheets/compounds, and specialized deburring tools are utilized by the machinist or tool maker to complete the fabrication process based on the part’s geometry and the requirements communicated by the engineering drawing.  Tedious and time-consuming hand work can add significant cost to a part; therefore if many identical parts are being produced, an automated deburring and finishing process is usually specified if possible.

Mass Finishing

Mass Finishing is a timed batch process that utilizes abrasive media and a rotating or vibrating process vessel to simultaneously deburr and finish multiple machined parts.  These machines process any surface that comes in contact with the media.  Ranging in size from small table top units used for processing rings and other jewelry to massive rectangular tub machines twenty feet long used for finishing aluminum aircraft parts. The processing vessels are generally fitted with a tough rubber liner to protect them from the media and prevent damage to the parts being processed.  There are countless combinations of media sizes, shapes and materials which are selected based on the machined part’s physical characteristics and how much material needs to be removed to achieve the desired surface finish.

Roller and Ball Burnishing

The process of burnishing is the plastic deformation of a surface due to sliding contact with another object.  There are many burnishing processes utilized by manufacturers today, however, the most common are roller burnishing and ball burnishing.  Burnishing does not remove any material, it is a small-scale forming operation that can improve the finish or hardness of the part’s surface.

Powered Brush, Belt and Disc Deburring and Finishing

These machines come in many shapes and sizes and utilize rotating abrasive discs, brushes and drums to process parts. They are best suited for sheet or plate material since parts are often transported through the processing equipment on a flat belt conveyor.  Some of these machines are engineered to produce the directional scratch marks known as a grain on flat sheet metal surfaces.  Robots arms can also be outfitted with compliant power tools and bonded abrasive media to process large 3-dimensional parts.  These robotic workcells are then programmed to deburr corners and finish surfaces in a repeatable and controllable fashion.

Abrasive Blasting

Solid particles of a selected abrasive media are accelerated, most commonly with compressed air, and directed by a nozzle so that they impact the part’s surface at a high rate of speed.  There are many different media materials, sizes and shapes that can be utilized depending on the hardness of the base metal and the surface effect desired.  Sand is a common and inexpensive material that is often utilized to clean and texture large metallic surfaces and prepare them for subsequent painting processes.  Glass beads, crushed walnut shells, dry ice and baking soda are examples of other media that can be used in abrasive blasting systems.  It is common for smaller parts to be placed into an enclosed cabinet for processing.  This glovebox enclosure contains the dust generated by the blasting process and protects the operator from the ricocheting media.  There are also robotic blasting systems and multi-nozzle machines available that automate the process and improve consistency and material removal rates.    

Electrochemical Deburring and Polishing

This is a method that finishes a machined part’s surfaces by means of anodic metal dissolution.  A part specific shaped tool is the cathode.  In conjunction with an electrolyte fluid, an anodic reaction is created between the tool and the part that removes surface material in a very precise manner.

Thermal Deburring

This process uses the ignition of a combustible gas within a pressurized chamber to remove burrs from machined components.  Because the burrs are much smaller than the component, they reach the auto-ignition point instantly and are vaporized in the oxygen-rich chamber.  An oxide powder is left across the component surfaces and may need to be cleaned prior to, or as part of subsequent coating processes.

Abrasive Flow Polishing and Deburring

The abrasive flow process uses the reciprocal flow of abrasive laden slurry to polish and deburr the surfaces and edges of a machined part.  Two vertically opposed cylinders pump the slurry back and forth through passages formed by the workpiece and special part specific tooling. This process is typically used to deburr and polish parts with complex internal features.

plasma treating metal parts

Plasma Surface Treatment

Plasma, the fourth state of matter, is a gas that’s been partially ionized and has been electrically charged with freely moving electrons in both the negative and positive state. Plasma flames can be used for pretreating surfaces of metallic parts prior to subsequent coating, printing or bonding operations. The plasma removes any foreign contaminants present on the surface of a material and also activates the surface at a molecular level significantly improving the adhesion characteristics of the base material.

Keller Technology is a world class manufacturer of vacuum and pressure vessels, process equipment, electro-mechanical sub-assemblies and complex machined parts.  Our well-equipped, state of the art manufacturing facility allows us to produce fabrications to exacting dimensional tolerances.

Contact us today with your most challenging fabrication and manufacturing projects.

Keller Advantage
Keller Advantage
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Quality Tested
Keller ISO Quality Management Certifications
Buffalo: ISO 9001
Buffalo: ISO 9001
Charlotte: ISO 9001, ISO 13485
Charlotte: ISO 9001, ISO 13485