Customer Reviews

Factory Physics

5 star:		(13)
4 star:		(3)
3 star:		(1)
2 star:		(1)
1 star:		(1)

 

 

As a supply chain consultant, oftentimes the quality of my work is directly impacted by the reference aids in my own personal library. "Factory Physics" is such a reference aid that has my work has benefitted from several times.

The book covers all of the traditional manufacturing topics you would expect in sufficient detail: inventory control, JIT, production scheduling, capacity planning, shop floor control, etc. But given that you can buy any number of other suitable, standard P&IC textbooks on these topics, that's not where the value is.

The value in "Factory Physics" lies in the unique content which presents manufacturing management in a "scientific" context. For example, there are chapters on 'Basic Factory Dynamics,' 'Variability Basics,' and 'The Corrupting Influence on Variability.' These chapters demonstrate how manufacturing managers and engineers can move away from the rule-of-thumb, heuristics-based approach to operations planning and control (which is so often is either a guessing game or not based on empirical data) to a more formal, rule- and data-driven approach.

For example, I have been in many factories where management had only a SWAG approach to modeling equipment reliabilities, cycle times and throughput volumes, which drive queues and thus impact shop floor inventory. This book gives you the tools to properly understand these dynamics, if these are important issues to you.

The content in the book on the corrupting influence of variability is a welcome harkening back to the ideas of Edward Deming, who consistently preached about the damage that variation can do when introduced into stable production environments. In my opinion, this is another example of the unique and rare content offered by "Factory Physics."

Other value-adding content includes discussions sprinkled throughout the book on the fallacies and disadvantages of age-old planning and control methodologies, such as MRP or EOQ. In a world where 99% of textbooks believe their only duty to the reader is to simply present laundry lists of all the planning techniques known to humankind, these critical commentaries are a breath of fresh air.

I don't recommend this book lightly, or to individuals who are only loosely associated with operations planning and control positions. Rather, I highly, highly recommend it to serious, mature manufacturing professionals who are not timid of higher level mathematics, statistics and probability theory. If not, the reader would probably not be able to realize the true value of the book and it would go unused.

A former client of mine, who was nice guy but a novice when it came to manufacturing issues, asked me if he should buy "Factory Physics" for his own use. My response to him was this: "If you wanted to learn more about physics you probably wouldn't order reprints of papers by Einstein, Hawking, Bohr, etc. You would go and buy something like 'Physics for Dummies' and start there. I suggest you do the same for manufacturing content."

Having worked with Spearman and Hopp at Northwestern during the formation of this book, I have been applying it's lessons in practical applications for over 5 years. The lessons learned from this book have provided me an intuition for reacting to and solving problems in manufacturing and business that has withstood the test of time.

Now, when a consultant, or a magazine, or my boss proclaims some great new solution, I don't compare the solution to some other proposed solution to try and figure out which is best. I compare all proposed solutions to the fundamental laws of factory physics to see which solution best suits my requirements.

The main drawback of the book is that it is a textbook and, as such, will require time to read and understand. On the other hand, the book reads well and is not one mathematical proof after another. The authors have based the book on solid science but have limited the extensive proofs for the appendix.

This book is a must-have reference and guide for anyone working in manufacturing or the business of manufacturing.

I have kilos of books on manufacturing and as a long practising and experienced Industrial Engineer, I would ditch 90% of them for "Factory Physics". Why ? For many good reasons; The authors succinctly state the condition of manufacturing in the USA today and its underestimated role in its contribution to the national economy. This condition is mirrored in other industrial economies. But that is just the start; there is the history of manufacturing management that puts its role in perspective; then the authors put the acronyms and fads in their place along with the messiahs and the missions and messages. They sort the wheat from the chaff.

The heart of "Factory Physics" is the authors' explanations of the dynamics of factory systems and their interactions; which are logically revealed and well exampled.

Further MRPs, JIT / Kanbans are constructively criticised and put into their appropriate roles and functions. No authors have previously so constructively questioned the validity of these programs and techniques and then come up with very logical and applicable alternatives.

But more ! In "Factory Physics" are the "Laws" of manufacturing systems; about 20 of them; These are the Laws that govern the 'behaviour' of factories and even the behaviour of the people's that run them. One can see these Laws in evidence in manufacturing plants at any time, anywhere and with any product.

The text of "Factory Physics" is a solid foundation for the understanding of manufacturing; the basics; the necessary 'instincts' to build on and the guiding models to synthesise solutions to classic production problems. But above all there are the Laws; that provide a constructive means for effectively analysing and managing manufacturing plants and systems.

If there was a prize to be awarded for a spearhead text for a "science of manufacturing" for the new millenium; then Messrs Hopp, Spearman and team should receive it for "Factory Physics".

This book must be the standard text for present and future Industrial and Manufacturing Engineers and Plant Managers.

Move over Maynard !

This book provides you with the fundamental insights of manufacturing and assembly. Even though I do not like statistics to much, the book is written in a understandable manner and provides the fundamental knowledge to understand what is going on in manufacturing. Based on this knowledge, the flaw of MRP-systems are even explained as well as the basics of JIT/Lean. The book provides mainly the hardfacts of this science and for practical people, reading first Quick-Response-Manufacturing (from Rajan Suri) might be the easier way for many of us and gives you the motivation to take a deeper look later on - as provided by Factory Physics.

Factory Physics describes not only how to describe a single workstation and the interactions between many of them, than as well the great importance of variability reduction in a production line and how to analyse it. CONWIP-lines, as a mix of push-pull, are a central key in this book and a simple way to analyse the performance of any system is provided by the book. This book, together with Quick-Response-Manufacturing (this book includes important softfactores as well) have changed drastically my way of operational thinking and given me a sense, which system to apply (QRM or JIT/Lean) and why. The insight can even be used for services as well. One central point is the utilisation of a workstation and the knowledge, that the more you reduce variability in arrivals and processing, the higher the utilisation can be - still achieving low lead times. You will find as well important and simple laws helping you out in the daily business (Little's law and queueing theory).

As for JIT/Lean, lead time reduction can use the same japanese tools:

- SMED: setup-time reduction (lot sizes for reduction in lead time and WIP)
- TPM: productive maintenance (higher machine availability and decrease of variability)
- ZQC: fool-proof quality inspection for Zero defects (against capacity lost and to decrease variability)

All the books mentionned above, have a big advantage over traditional SCM-books: they provide you with a framework how to trim a single chain-element of the supply-chain and therefore how to built the whole supply chain. The operational strategy should be derived from the overall company strategy and with this new insights you can tailor a unique production system that fits your company's goals - or even give you an advantage over your competition. Anyway, it will not make obsolet the importance of having a sound and consistant overall business strategy (for your markets) first!

Enjoy reading, Best Regards

This definetely is a good book, the language and the examples used are very illustrative and the content shows that the authors are very experienced and know what they are talking about. However, I believe that this book should not be used as an introduction to production planning and control, this is more something to read after some introduction to those techniques has been acquired, and you are seeking to sharpen your ability to use them. They offer good buy few, very few examples, and the questions and proposed exercises in the back do not have answers. Not good for an introductory class on the subject, a must for those who have already some knowledge about the subject.

I am a researcher and statistician with a background of 20 years experience in applied business and academics. One day I stumbled over Spearman and Hopps "Factory Physics". Literally... The book consists of three parts: An interesting historical and technical introduction to the development of SCM as a science ("Origin of SCM"), followed by the elaboration as a framework ("Factory Physics"), and finally "Principles in Practice" as the third part. The more I read the book, the longer got my list of fundamental criticisms:
1) The main formulas fit on four (!) pages, the inner sides of the front and back cover. The remaining over 700+ (!) pages are used to explain the formulas. This book is incredibly long-winded, repeating all over, and still could have explained a lot shorter and better. Not to mention the lack of definitions, symbols not explained, and also the usual typos and errors.
2) The formulas celebrated as "physics" are nothing more than simple mathematical formulas. From this follow several problems met also in corporate practice: Complex SCM practice processes can not be modeled by simple mathematical formulas and EXCEL. One reason are the formulas themselves: Several researchers have demonstrated that the "Factory Physics" formulas are not suitable for complex SCM processes, for example Chen and Ye (2002): "Our analysis suggests that we should be very cautious about the applicability of these laws". From this again follows that companies will be faced with massive problems optimize their SCM processes with the "Factory Physics" approach.
3) Also the presentation of "Factory Physics" formulas for simple processes has its own problems: Being far from self-critical, the authors hide fundamental problems of the Linear Programming (LP) approach: For example: Effects have to be known in advance, cross-products are not allowed, and that it requires linearity (thats why it is called LP, guys!). I could go on. Presented like this, LP is nothing more than a trial-and-error approach.
4) Forecasting is being repeatedly devalued by just repeatly stating "forecasts are always wrong". No joke. As if professional forecasts dont exist. As if high-performance forecasting systems like SAS dont exist. As if standard forecasting text books of authors like Makridakis, Yaffee or others dont exist. Well, I assume Hopp/Spearman havent read them judging by the simple extrapolative approaches presented. ARIMA? Not even mentioned. The presentation gets close to arrogant, especially when time and again emphasizing the acceptability of their approximations of their own approaches. Above all, the technical development of SCM systems progressed so much in the meantime that the disqualification of SAP can only be described as outdated. Hoping at first that someone actually may have made it to create a complete SCM framework to systematize the possibilities approaches like, for example data mining, may offer, I do have to realize after reading the last page of the book that it has failed miserably. The authors like to hack on consultants, other approaches or systems, or statistical approaches. Self-criticism that would be quite appropriate here is far and wide not to be seen. Reviews trying to raise this imposition on a level with Einstein, cant be taken seriously. I can only assume that this person has -no- idea of the possibilities of modern data processing also in SCM. I cannot recommend to buy this book for these and other reasons. If you still want/need to buy it: Now you cant say you have not be warned.

This was a required text for my Production and Mgmt course during my undergrad studies as an Industrial and Ops Engineer at the U of Michigan in 2000. Priot to taking the course, I had very little knowledge of how ops research/optiimization tied in with real world settings. Lucky for me, the course was taught by an wonderful, demanding professor who unfortunately had to leave and now is at the U of Cinnatti. Anyway, I was able to gain tremendous understanding of how statistics, queueing theories, game thoeries, and factory mgmt all got tied into one. It was this book that tied all the pieces together and push me forward toward my career path. I continue to use this book as reference and interesting reads in my continued involvement in the Supply Chain areas and optimization areas in the tech industry. This book WILL build a firm foundation for anyone who gives an effort and has an interest in the subject. What you do with the knowledge, is up to you in the future, since many of these concepts take time and experience to apply in the real world.

Hopp and Spearman wrote the classic issues, manufacturing system, in elegant format. The fundamental of manufacturing systems is deliberately compiled in a single textbook. If you like Askin and Standridge book (1994), you will love this book as well. One thing that forbids me to put 5 stars is this book doesn't have the "material flow/facilities design" issue, which I believe it is the foundation of manufacturing management too. I thought the facilities planning would be included in 2nd edition- but nope :( May be in 3rd edition... maybe... :(

I have not applied the total conceps from this excellent book. I just have used the elemental ones and I obtained great results in Inventory reductions. If you really want to improve your business it is a good idea to start at the begining... start with the basics with Factory Physics. You do not need to learn sofisticated techniques or expensive tools, you just need to take the original tools and develop them in order to improve your processes. This is the essential matter of this book.

Product is great. Just like the regular 3rd edition, but paperback and, I believe, in a slightly smaller trim, making it easier to carry and have around.