A Deep Dive on Process Modeling

Building and maintaining your multivariable process map: where to start, how to develop, and who should own this critical tool for managing your product development process and understanding risk. (Post 7)

In the previous post, I rolled out some thoughts on the value of multivariable process mapping, even very early in product and process development.  I showed you the basic construct and then left you hanging.  Apologies, but the last chapter was getting too long to include the details, and it wasn’t adding anything to what I was trying to convince you of, which is that your limited and precious resources are best spent creating these colorful, but somewhat dry and detailed spreadsheets.

Continuing the commercialization discussion of the “How” with multivariable process maps

 This installment will go through the specifics of the process map in detail. This document is (as I argued) a key model to the success of your product – a repository for initial information, and, as it evolves, the key source of ongoing process design as you move through the Product Life Cycle. Further, given the crucial nature of the accuracy of the data in the process map, another key decision will be: who puts this together (and keeps it up to date)? We will discuss the ideal member of your team to author the multivariable process map and own the upkeep of its contents.

Building the initial Multivariable Process Map

In the previous post, I emphasized building an initial process map very early on, as the product is still a rough vision. Create a simple spreadsheet, with rows for each step in the build or implementation process. These will start as broad steps, continually expanded into more granular steps as the details of your design are fleshed out. Many items will be blank early on. But these blank spaces will provide some sense of where there are unknowns in the build process, where there is still design work to do, and where more risks may lurk.

The columns or headers in the spreadsheet fall into these major categories, explored in much more detail below.

Index – the description of this step, with references to other documents if applicable.

Process Details – the details of this step, including duration, yield, and costs (as summarized from other columns).

Touch Work – Description and duration of hands-on labor required for this step.

Capital, Expensed Items, Consumables – Materials and tools associated with this step, key for cost summarization.

The nitty gritty

And now for some less exhilarating – yet still, hopefully, inspiring - discussions on the specifics of the process map headings: what do they mean and why do we capture them, even early in a product’s development?  At this point, Service Based startups might not benefit as much, but some of the concepts in this chapter might be useful, if you’re conceiving of a “call center”, customer support operation, or other service model endeavor.  Even customer service and order taking models align well.

Index

Op. Numbers (Operation Numbers):  These are simply numbers, usually by 10’s (010, 020, 030, that allow numbering a tracking of process steps and transformations.  Why 10’s?  You have 9 places to add steps you missed.

Type:  This is a basic descriptor of families of operations aligned with the specific process and manufacturing type.  For example, if it is a chemical formulation process, then they might be: Weigh, Material Add, Mixing, Polymerization, Heating, Cooling, Tempering.  For semiconductor process:  Plasma Etch, Metal Plating, Load Wafer, Metal Deposition, Unload Carrier, Wafer Heat.  For a micro electrical assembly:  Die/Component Pick and Place (P&P), solder dispense, adhesive dispense, solder, wire bond.  These should be large buckets, of which process descriptions fall into.  For example, there are many types of plasma etch types and systems.  Plating dependent metal types and desired thickness and uniformity.  Chemical formulations can use weight or volume for material add.

SOP Doc. Number (Standard Operating Procedure Document Number):  These documents are also called process sheets, assembly guides, run sheets, and work instructions.  In the beginning of a product’s development, these might be notebook or process journal entries.  The intent is to leave these as a placeholder for future formalization of these steps.  If you don’t have them, leave it blank.

Process Description:  Using the “Type” reference above, this would specific variety of process type.  For Example:  O2 plasma etch (of Plasm Etch); cooled fixed RPM mixing (of Mixing), Forced Air Cooling (of Cooling); Gold Sputter (Metal Deposition); VISCEL P&P (Component Pick and Place).  Make these specific enough to give the community an idea of intent of the process.

Transformation:  This is a more difficult concept, representing the move from one state to another. Most steps in the process likely do not involve a state transformation, but if they do, it is important to note it here.  It might be an epoxy exothermically curing because the user applied a mixture of Part A and Part B, and letting it cure to secure a component or seal joint; the transformation would be cure.   It could be going from an untested state to a tested and calibrated state; the transformation would be functional test.  Sometimes, particularly in material and chemical compounding, there are interim states, requiring certain timing and waiting to achieve desirable outcomes.   These are often controlled cooling or tempering that allow chemical reactions or energy states to be maintained and stopped.  The often have names based in the company’s nomenclature, like colloidal dispersion, filler agglomeration, or catalyst settling.  The basic rule is that a transformation is identified if it’s critical to the performance of the process and process capability.

Process Details

Man-Minutes per unit:  This is the time it takes to complete the process from the beginning to end.  If it’s loading an oven, it might be 2 minutes.  If it’s compounding a chemical solution or a complex assembly step, it might be 20 minutes.  If it’s greater than 30 minutes, you might have the granularity you need, in that too many process steps are being bundled.  These are often call time standards.

Machine Minutes per unit:  The big difference between Man-Minutes per unit and Machine Minutes per unit, is that sometime a machine is manned and sometimes it’s not.   The classic example is a batch oven, where an operator or technician takes 6 minutes to load and unload trays into an oven, and the bake cycle is 60 minutes.  The applied labor (Touch Work) is 5 minutes , and the processes cycle time is 60 minutes (machine time).  Of the 60 minutes, 10% is touch work.

Process Yield:  In process intensive, transformation intensive processes, yield is a big deal.  What is yield?  The percentage of good units divided by the started units.  If you start 100 units and get 95 good units, your yield is 95%.  Conversely, your defect percentage is equal to 1 - Yield or 5%.   Most people involved in processing have an idea of what this ratio is.  There will probably be an entire blog chapter on Yields, how they can impact cost and capacity, and why they are one of the Key Performance Indicators (KPI) in certain industries. 

Material Cost:  This variable is simply the total cost of all materials used or consumed in this process step.  This is less critical during the early stage of process map development and becomes more important as the product and process mature.  Understand that sometimes, materials are so rare and/or expensive, everyone understands them early in development.  If available, we will capture. 

Capital Equipment Cost:   If a process step requires dedicated, expensive, sometimes borrowed, or shared resources, understanding this sooner than later is important.  For example, start-ups that use wafer foundries are often shocked by the sticker price of the equipment they counted on when they have outgrown the foundry’s operating rules.  Otherwise, even if they are estimates, it is worthwhile to start populating this cost field as soon as possible.  You’ll be surprised how quickly such costs add up.  This is the total cost of the Capital (Equip1, Equip2, Equip3) fields’ equipment.

Capital (Equip1, Equip2, Equip3):  Capital is an accounting term for equipment, usually costing greater than $1000 dollars.  In larger companies, these capital values would be depreciated over time.  One of the model’s basic assumptions is that the plant’s production space is provided for, so you don’t have to list every table, chair, and work light.  These quantities are usually derived later from the number of workstations the model says you will need for a given production model (yes, the model will tell you things…).  In the beginning, assume one station.  Equip1 (Equipment1) represents a machine required to perform the work in the process step.

"Touch" Work, Settings, Specs (Work1, Work2, Work3, Work4, Work5, Work6):

Touch Work is actual, hands-on labor, to complete the process step.  It can also be time associated with set-up; although if set-up is long and complex, that should be broken out.  Same thing with process validation and quality assurance.

Settings are machine states in which a technician or operator sets a piece of equipment to initiate, transform and complete a process step.  The simplest is setting an oven.  Sometimes settings are complex, involving multiple states and domains, temperature increasing over time and pressure.

Spec (Specifications) are, well, specifications.  The formal definition is:  an act of describing or identifying something precisely or of stating a precise requirement.  Spec is nomenclature, an abbreviation and shorthand.  Specifications are the target or limits, measuring the how well the “How” achieved the desired “What”.   They can be Final Specifications facing the customer, or Interim Specifications, that if met, enable the next steps in your process.  They can be after the fact, like Test and Quality Specifications.  They can be actively controlled and executed specifications like Process Specifications.   The notion is that Specifications are a formal vehicle to define important inputs and outputs in your process.

Expensed Items (Exp1, Exp2, Exp3):  Where capital is expensive, expensed items are typically lower cost items, which likely are not customized for your process.  Examples are solder irons, hot plates, and hand tools.  But while these might be generic in nature, their specificity could be critical.  For example, a hot plate might have integrated magnetic stirring or not.  This is a big deal in chemical compounding.

Consumables (Consume1, Consume2, Consume3, Consume4, Consume5):  Consumables are not necessarily low cost.  Consumables include equipment or materials that are consumed during completing the process. For example, these could include swabs or wipes.  They could include chemicals to prepare containers or surfaces.  They could be gases or catalysts.  In all these cases, if it’s a process intensive product, these consumables will have their own specifications for purity and cleanliness.  These are not materials that are actually part of the end product, which is controlled in another tool, called a Bill of Materials (BOM).  I’ll discuss BOMs, Routings, and their importance in another chapter.

 The keeper of the (figurative) keys

At this point, I’d concentrate on reviewing these elements, start to account for what data is available and where, and think about who is best suited in your organization to maintain these process maps and other modeling tools. Consider this individual carefully. 

  • From my experience, the charismatic product development leader is not the best choice; they will lose interest in the details, and without knowing it, devalue the effort in the eyes of the employees.  

  • Another candidate who is often chosen to maintain this would be a hard-core quality professional, who will likely be too rigid, risk adverse and/or cautious to allow the team flourish and grow into the knowledge, because they will be freaking out that every box isn’t filled out with information (which is likely not available) and is in the correctly sized and colored font. 

  • I know these are two ends of the spectrum, and I did this on purpose; maybe my characterizations are a bit extreme and bordering on offensive.  Perhaps so, but in my experience, they are not untrue. 

  • And again, startups can’t afford as many mistakes as larger established companies can absorb.  There is no perfect candidate, but the one that work best might be an introvert (privately) and who is social enough (publicly); someone who has some extrovert tendencies, willing to dig to gather information from sometimes reluctant coworkers; someone who likes to actively listen and ask clarifying questions; and who values quantitative data and using it to make decisions.  A little bit of anal retentiveness does not hurt, and having good documentation management practices helps.

Professional characteristics of a good candidate to manage the process map:

  • Analysts with engineering backgrounds.

  • Process engineers that love system modelling.

  • Production professionals who have managed transformation processes (and have the scars to show it).

Professional characteristics of a not-so-good candidate to manage the process map:

  • The long and suffering intern or coop. They are perishable and don’t have the authority, Influence or power needed to gather accurate information from other members of the team.

  • The person who’s failed at everything they touch but the “culture” can’t do the right thing and fire them. It may be tempting to utilize this person – they probably have time on their hands – but maintaining an accurate process map is too critical to the success of the project.

  • A founder or executive, because people may not tell them the tough truths and they hold too much influence and power.

In the end, this team member must be comfortable with the power and influence they will gain, and management must be comfortable delegating that authority to them, letting the team develop the content and the model.