by Rick Price, Process Control Supervisor, Spokane Precision Castings Division of Spokane Industries
I've always been fascinated with metals. When I was a young child, I used to stoke up the campfire as a Boy Scout just to watch aluminum cans melt. All I knew about metals at that time was that aluminum and steel were different. As I worked different jobs at Spokane Industries I learned about different alloys, chemistry and metallurgy and how those elements affect the steel. Though I am not a metallurgist by trade, I have acquired a great depth of knowledge through my thirst for learning and a variety of avenues of study and research afforded me through my employment at Spokane Industries.
SPOKANE INDUSTRIES, through its Spokane Steel Castings, Spokane Metal Products and Spokane Precision Castings operations, has been providing customers around the world with cost effective solutions to their steel castings and industrial fabrication needs since 1952. Today, SPOKANE INDUSTRIES is a modern diversified company with plant and manufacturing facilities occupying more than 240,000 square feet. The company serves a large number of customers in many industries -- from aerospace, construction and agriculture, to transportation, aggregate processing, and manufacturing.
Alloy selection is a key factor when designing an investment casting. Strength, ductility, toughness, hardness, machinability, weldability, wear resistance and corrosion resistance are just a few of the design criteria that must be taken into consideration. In ferrous alloys for example, carbon plays an important role in determining strength and hardness. Other elements, such as molybdenum, chromium and nickel effect through hardness, or hardenability.
Chromium imparts corrosion and oxidation resistance in stainless steel when present in amounts greater than about 11%. Once the proper combination of various elements and weight percentages is determined, most alloys are then heat treated to attain the final properties. Castings are generally subjected to a high temperature soak, quenched at a pre-determined rate and then tempered at an intermediate temperature.
The chemistry of every heat of metal poured at Spokane Precision Castings is analyzed to insure that we meet customer specifications. Metal samples are taken at various stages throughout each heat and sparked in an optical emission spectrometer. During this process, each element emits a unique wavelength of light that is diffracted through a grating and directed to individual photomultiplier tubes. The measured light intensity is translated into a weight percentage for over a dozen elements. Each element has a range it must fall within for the metal to be in specification and to meet certain requirements.
Spokane Precision Castings runs this process on both a preliminary as well as a final sample to ensure consistency. We check chemistry, make alloy additions, pour the heat, and then test another button after the chemistry has been adjusted as the final chemistry for that heat. Our company is in the process of testing a new product to take a sample out of the stream of molten metal as it is being poured into the casting. This will improve our final chemistry analysis and results.
Currently, Spokane Precision Castings is working on creating a range of castings that would be made out of a cobalt-based alloy. Cobalt has many different properties than an iron-based alloy i.e. higher corrosion resistance, good wear properties, and is often used as medical implants.
As the company progresses, we want to improve Spokane Industries Quality Assurance efficiencies to transfer the knowledge of the Quality Assurance personnel to the technicians on the production floor. This constant push to resolve problems at the lowest level helps to rectify in process issues as they occur. We currently are implementing written and visual instructions to facilitate this transfer of knowledge and to augment our ongoing training and quest for continuous improvement.
Jeff Kuntz, Production Manager at Spokane Precision Castings Division of Spokane Industries states "to make a quality investment casting takes a great understanding of materials, a solid grasp on how those materials react with one another, a broad array of process controls and a quest for quality. Making a thousand castings as opposed to a single casting is key in understanding the investment casting industry. The investment casting process is very effective at producing consistent quality over a large run of parts. That being said, it is only true when the organization recognizes the dependency on tight process and quality controls in order to meet all customer demands as we do here at Spokane Precision Castings."
Thursday, May 9, 2013
Wednesday, May 1, 2013
Lean Manufacturing in the Steel Castings Industry
by Billy Newman
Lean Manufacturing Definition: Lean manufacturing or lean production, which is often known simply as "Lean", is a production practice that considers the expenditure of resources for any goal other than the creation of value for the end customer to be wasteful, and thus a target for elimination. In a more basic term, More value with less work. Lean manufacturing is a generic process management philosophy derived mostly from the Toyota Production System (TPS) (hence the term Toyotism is also prevalent) and identified as "Lean" only in the 1990s. It is renowned for its focus on reduction of the original Toyota seven wastes in order to improve overall customer value, but there are varying perspectives on how this is best achieved. The steady growth of Toyota, from a small company to the world's largest automaker has focused attention on how it has achieved this.
Lean manufacturing is a variation on the theme of efficiency; it is a present-day instance of the larger recurring theme in human life of increasing efficiency, decreasing waste, and using empirical methods to decide what matters, rather than uncritically accepting pre-existing ideas of what matters. Thus it is a chapter in the larger narrative that also includes, for example, the folk wisdom of thrift, time and motion study, Taylorism, the Efficiency Movement, and Fordism. Lean manufacturing is often seen, with the benefit of hindsight, as a progression from, or a better attempt at the same goal of, earlier efficiency efforts, that is, picking up where earlier leaders like Taylor or Ford left off, and learning from their mistakes.
Lean Manufacturing focuses on two main points, reduction of through-put time and elimination of waste. Through-put can be described as the time it takes an order to be received until it is on the shipping dock. Elimination of waste can be seen in several different areas. The Seven Wastes are: 1) Motion; any wasted motion to pick up or stack, walk and/or lack of direction or access, 2) Over-production; labor needed to process more than is needed, 3) Transport; multiple locations for the same information and/or wasted effort to transport work, 4) Inventory; maintaining excess inventory of raw materials, work in process, and/or finished goods, along with outdated or obsolete information, 5) Processing; doing more work than is necessary, 6) Waiting; any non-work time, and 7) Defects; everything required to rework or repair form.
For the Steel Castings Division of Spokane Industries, lean manufacturing is the single most effective strategy that will allow us to improve our quality while reducing our overall costs. In this commitment to Lean, we started with 6S, which is an acronym composed of Safety, Sort, Simplify, Shine, Standardize and Sustain.
Initiating the 6S practices made sense for a number of reasons. It was obvious the old way of approaching business practices was outdated. With obvious waste all around us it was easy to see that our production levels had plateaued, but the culture of the employees was not such that change would happen on its own. There was a veteran work force that had been doing it the same way for years, and they werent about to change, because in their view it wasnt broken. The visible change needed was provided by 6S to help jumpstart a revamped culture throughout the foundry.
We broke the foundry down into 10 sections and began implementing 6S. In each section we did an introduction class on 6S and Lean manufacturing, basically subscribing to a train-do model. Each member would actively participate in a kaizen event within a week of the class. In some cases we did the same section multiple times in order to achieve the desired results. At least one event was participated in by every foundry employee.
An additional step of our Lean journey began with the understanding of Autonomous Maintenance. Autonomous maintenance is the initial standard in Total Productive Maintenance or TPM. TPM is a proactive approach that essentially looks to reduce inventory (spare parts) and catastrophic failures by preventative measures.
As we proceed, we will continue our 6S and autonomous maintenance efforts while we perform Value Stream Mapping (VSM) of our processes. VSM is the series of processes that directly create value for the external customer by efficiently streamlining our work flows. We will do this to identify safety concerns, waste, bottlenecks, and communication breakdowns.
Tyrus Tenold, President of Foundry Operations for Spokane Industries, states, "To this point, a growing asset to Spokane Steel Castings are our Lean Manufacturing practices. As the culture continues to change, we implement new ideas on a regular basis. We have fully embraced Lean Manufacturing and we now look forward to seeing continuous improvements for the mutual benefits of customers and our ourselves."
Lean Manufacturing Definition: Lean manufacturing or lean production, which is often known simply as "Lean", is a production practice that considers the expenditure of resources for any goal other than the creation of value for the end customer to be wasteful, and thus a target for elimination. In a more basic term, More value with less work. Lean manufacturing is a generic process management philosophy derived mostly from the Toyota Production System (TPS) (hence the term Toyotism is also prevalent) and identified as "Lean" only in the 1990s. It is renowned for its focus on reduction of the original Toyota seven wastes in order to improve overall customer value, but there are varying perspectives on how this is best achieved. The steady growth of Toyota, from a small company to the world's largest automaker has focused attention on how it has achieved this.
Lean manufacturing is a variation on the theme of efficiency; it is a present-day instance of the larger recurring theme in human life of increasing efficiency, decreasing waste, and using empirical methods to decide what matters, rather than uncritically accepting pre-existing ideas of what matters. Thus it is a chapter in the larger narrative that also includes, for example, the folk wisdom of thrift, time and motion study, Taylorism, the Efficiency Movement, and Fordism. Lean manufacturing is often seen, with the benefit of hindsight, as a progression from, or a better attempt at the same goal of, earlier efficiency efforts, that is, picking up where earlier leaders like Taylor or Ford left off, and learning from their mistakes.
Lean Manufacturing focuses on two main points, reduction of through-put time and elimination of waste. Through-put can be described as the time it takes an order to be received until it is on the shipping dock. Elimination of waste can be seen in several different areas. The Seven Wastes are: 1) Motion; any wasted motion to pick up or stack, walk and/or lack of direction or access, 2) Over-production; labor needed to process more than is needed, 3) Transport; multiple locations for the same information and/or wasted effort to transport work, 4) Inventory; maintaining excess inventory of raw materials, work in process, and/or finished goods, along with outdated or obsolete information, 5) Processing; doing more work than is necessary, 6) Waiting; any non-work time, and 7) Defects; everything required to rework or repair form.
For the Steel Castings Division of Spokane Industries, lean manufacturing is the single most effective strategy that will allow us to improve our quality while reducing our overall costs. In this commitment to Lean, we started with 6S, which is an acronym composed of Safety, Sort, Simplify, Shine, Standardize and Sustain.
Initiating the 6S practices made sense for a number of reasons. It was obvious the old way of approaching business practices was outdated. With obvious waste all around us it was easy to see that our production levels had plateaued, but the culture of the employees was not such that change would happen on its own. There was a veteran work force that had been doing it the same way for years, and they werent about to change, because in their view it wasnt broken. The visible change needed was provided by 6S to help jumpstart a revamped culture throughout the foundry.
We broke the foundry down into 10 sections and began implementing 6S. In each section we did an introduction class on 6S and Lean manufacturing, basically subscribing to a train-do model. Each member would actively participate in a kaizen event within a week of the class. In some cases we did the same section multiple times in order to achieve the desired results. At least one event was participated in by every foundry employee.
An additional step of our Lean journey began with the understanding of Autonomous Maintenance. Autonomous maintenance is the initial standard in Total Productive Maintenance or TPM. TPM is a proactive approach that essentially looks to reduce inventory (spare parts) and catastrophic failures by preventative measures.
As we proceed, we will continue our 6S and autonomous maintenance efforts while we perform Value Stream Mapping (VSM) of our processes. VSM is the series of processes that directly create value for the external customer by efficiently streamlining our work flows. We will do this to identify safety concerns, waste, bottlenecks, and communication breakdowns.
Tyrus Tenold, President of Foundry Operations for Spokane Industries, states, "To this point, a growing asset to Spokane Steel Castings are our Lean Manufacturing practices. As the culture continues to change, we implement new ideas on a regular basis. We have fully embraced Lean Manufacturing and we now look forward to seeing continuous improvements for the mutual benefits of customers and our ourselves."
Subscribe to:
Posts (Atom)