Every Cost Engineer has been tasked with creating a SHOULD COST on a process they are unfamiliar with and the software of choice does not have a method to reliable CYCLE TIME. So what do you do? You may do days of research, reading old text books, search the internet and maybe even have to visit manufactures or business that utilize this technology that you are unaware of.
You probably are asking yourself, “Hasn’t someone else had this same request? I can’t be the first to try to model this process. Is there a place I can get help?” This is it.
The idea is that if you have developed a method of calculating a CYCLE TIME for a unique process, post it here for others to use. If you need a CYCLE TIME calculator for a process you are unfamiliar with, check here first. If you can’t find on that fits your need, ask the community through the comments section.
NOTE: 1) To add a CYCLE TIME calculator, please use the contact us link on this sight. The calculator can be in either Excel or Word format. The site administrator will add it to the list. 2) Use the calculator at your own risk. It would be strongly advised that you sense check the data, method and results prior to implementing within your own work.
DISCLAIMER: Uses of any calculators are at your own risk. Calculations found here are by no means an endorsement of either for calculation or the author by the Society of Cost Engineers.
Injection Molding Cycle Time Calculator
Lathe and VMC cycle time calculator
Roll forming (video approved for reuse by aPriori Technologies). Critical cost driver details of roll forming are discussed in this video. https://youtu.be/JaGqjWQWVwk
Stamping Blank and Tonnage Calculator
I am looking for cold forging cycle time calculator.
I’m not an expert at cold forging but hoping others will correct me.
Usually, the “forging” is in the order of < a second per hit. I think the key becomes how many hits and method of transfer?
If this is lower volume, they may be set up on a transfer style line so the time may become additive. If it’s higher volume it may be progressive style and therefore it’s only the time per the longest hit (another topic altogether).
Video I found on YouTube https://youtu.be/VCUJu-5z–s
Anyone care to correct?
Thanks for the help.
vinod.goranalli@gmail.com
Please share the excel for calculating cycle time and tonnage for forged parts
Again, not a forging expert but I found this online. Please try it and let me know what you think. If it’s not accurate we will take it down. Welcome your feedback!
For a time I would use the “Strike Speed” or Strokes per minute. When you depreciate the cost of the equipment correctly, say over 3 shifts, 5 or 6 days a week and anywhere from 7 to 20 year depreciation, I don’t think the machine cost will be a big driver. Similarly labor should be shared across multiple presses and there labor should be minimal as well.
COLD FORGING
F=25 x (3.5~6.3) x K x A
F = Force Required
K = Steel Coefficient (0.9 for low carbon, 1 for medium and low carbon alloy steel, 1.1 for medium low alloy steel and 1.25 for high alloy structural steel)
A = Total deformation area of forging plan (Including Skin and flash) (cm2)
Use lower limit (3.5) for transfer type or low productivity
Use higher limit (6.3) for progressive dies and high productivity
HOT FORGING
F = (64~73) x K x A
K = Steel Coefficient (0.9 for low carbon, 1 for medium and low carbon alloy steel, 1.1 for medium low alloy steel and 1.25 for high alloy structural steel)
A = Projected area of the forging including Flash (cm2)
Speeds
Steam Hammer Screw Press Crank Press Die Forging Hammer
Strike Speed (m/s) 4-7 0.6-0.8 0.3-0.7 4-6
Cold Strike Time (ms) 2-3 30-60 30-60 2-3
Forming Time (ms) 5-15 30-150 80-120 5-15
Strike Speed 80-100 6-15 40-80 80-110
Source: https://www.machinemfg.com/forging-press-selection-and-tonnage-calculation/
A bit easier to read
Steam Hammer
Strike Speed (m/s) 4-7
Cold Strike Time (ms) 2-3
Forming Time (ms) 5-15
Strike Speed 80-100 6-15
Screw Press
Strike Speed (m/s) 0.6-0.8
Cold Strike Time (ms) 30-60
Forming Time (ms) 30-150
Strike Speed 40-80
Crank Press
Strike Speed (m/s) 0.3-0.7
Cold Strike Time (ms) 30-60
Forming Time (ms) 80-120
Strike Speed 40-80
Die Forging Hammer
Strike Speed (m/s) 4-6
Cold Strike Time (ms) 2-3
Forming Time (ms) 5-15
Strike Speed 80-110
Source: https://www.machinemfg.com/forging-press-selection-and-tonnage-calculation/
Can I have a steel material prices( either link or website) for the grades S235 & S355 and its equivalent from the past six months
K Laxman Sarat,
Unfortunately we cannot yet provide you with pricing on materials. We are working on a method to do this but as I think you can confirm, this is s difficult task. There are endless materials in nearly as many forms, i.e rod, billet, sheet, tight tolerance etc. Then there is also the question as to what “price” or “cost” are you looking for? Do you want to know what you can buy it for at a certain volume or do you want to know what it costs to produce? The answer to this depends on how you are using this information.
I hope others see your request and may point you in the right direction. I can tell you that there are a few steel suppliers that that list their prices on line, one I know of for fact is AK Steel.
Sorry for not providing the answer you wanted but I hope you understand the scope of what you are asking.
Thanks
Jerry Collins
Owner and Founder
Society of Cost Engnieers
Hello Aditya, you’re welcome.
For calculating these cycle times you have to think like the programmer of the machine-tool, and add each operation to come up with the total cycle time: loading and unloading time, pure cutting time for each separate step (here is where you need to check for the proper cutting parameters -speeds and feeds-), tool change time, tool approximation time, and any other extra your machine might have, like tool-check sensing, or 4th-5th axis rotation. I suggest using an Excel file, I can share one with you if you send me your email. Mine is lhernandez@societyofcostengineers.com.
Hi Leo, I sent you a email. I am in similar situation and need some help. Can you please send me a copy? Thanks
Jeff Guo
Can you please share tonnage and cycle time calculator for injection molding parts.
Sunil,
Just posted.
Thanks
Jerry Collins
Owner and Founder
Society of Cost Engineers
Hi,
I am struggling for the tooling cost of Sheet metal for stage tooling, progressive tooling and for plastics I am looking for injection molding , blow molding, Thermoforming (Vacuum forming,pressure forming and mechanical forming) tooling cost.
Hello Trimm,
This has been an issue for as long as I’ve been doing Cost Modeling. There are some software systems that can predict the cost of tooling decently. Siemens comes to mind. Another approach is to treat it as an assembly or an assembly of machined components with a volume of 1.
I’d like to hear for the rest of the members on this topic.
Thanks
Jerry Collins
cycle time calculations Based on Machine -material -tools -coolant – machine stability Casting and forgings need more precise selection
Clamping and parts complex shapes
Need experience M-M-M man material and machine