From there we can calculate the kfactor and the bend deduction. So i am looking for the parameters for 304 ss that will have the same outcome. So, basically, over here under the sheet metal folder,at the very top, right click,and click on edit feature. It reflects all real but unknown distortions in the bend region.
The following equation relates the k factor to the bend allowance. The k factor is the most important and elusive variable of bending, because it varies both as a function of the material and according to parameters such as angle and tooling. For instance right now in solidworks for say 11 ga sheet metal i use a bend radii of 0. Mar 23, 2018 sheet metal design series by design hub. The kfactor is the ratio of the neutral axis location t to the material thickness mt. This change in sheet length depends on the position of neutral axis or k factor. Input material thickness and and inner radius to get the data of k factor, y factor, neutral layer.
Learning to accurately layout and bend sheet metal is a very useful exercise. While modern bend deduction charts now are reasonably accurate, historically bend calculation charts, both for bend allowances and bend deductions, were notorious. K factor is actually the ratio of the offset t of the neutral axis from the inside bend and the thickness of the sheet t when a piece of sheet metal is bent. In general, the tooling only touches the sheet metal along these 3 lines. Mathematically k factor value is equal to the ratio of position of neutral axis and sheet thickness. Here are a few tips that will let you make accurate, clean, and professionallooking bends when youre working with sheet metal. Tight bend radius gradual bend radius k factor effectively 50%t max. Sheet metal bending design tips, bend allowance, k factor, etc.
Additionally, sheets with bends are stiffer than their flat counterparts. The line where the transition from compression to stretching occurs is called the neutral axis. Or yfactor in the case of proe where yfactor kfactor. Sheet metal is an external workbench evolved to design and unfold sheet metal parts. K factors are a great tool for developing flat blanks for sheet. Kfactors, yfactors, and press brake bending precision. Dec 27, 2016 when working in solidworks to create sheet metal designs, we will often need to know three important values. Bend allowances are calculated using a kfactor as follows. The kfactor is fundamental to designing precise sheet metal products. You can easily modify the material thickness, inside radius and kfactor for each thickness at the top of each column. With this free online tool we quickly get the sheet metal bend deduction, and therefore the sheet metal blank initial flat length, from the finished part measurements you only have to insert interior angle, flange lengths, k factor.
Kfactors are a great tool for developing flat blanks for sheet. Since the inside compression can not exceed the outside tension, the k factor can never exceed. Kfactor a constant determined by dividing the thickness of the sheet by the location of the neutral axis, which is the part of sheet metal that does not change length. The k factor is fundamental to designing precise sheet metal products. The k factor is the ratio of the neutral axis location t to the material thickness mt. For example, a flat sheet of aluminum is less stiff than that same sheet of aluminum bent into a v cross section. Best way to calculate k factor in sheet metal is by reverse engineering. The art and science of bending sheet metal hackaday. In this article we are going to back up a bit, and provide some of the theory necessary to understanding how we go about the process of converting a flat piece of sheet metal into a complex sheet metal component. Oct, 2011 unfold your sheet metal part and by adjusting the k factor try to bring your bending line in a desirable distance. Sep 12, 2018 the k factor is fundamental to designing precise sheet metal products. The sheet metal model built with the sheet metal addon rear. It ultimately allows you to estimate the amount of stretch without knowing what type of material you are bending. Sheet metal basicsmechanical engineering interview questions,dimus tutorials.
Fabrication calculator for kfactor, yfactor, bend allowance. The difference between k factor, bend allowance and bend deduction in solidworks. Bend radii and k factors for 304 stainless steel sheet. It is used to calculate sheet metal flat length flatpattern. Sheet metal parts are some of the most important semifinished products.
A drawbead model with sheet metal passing through multiple bending unbending processes was employed in this study to understand the springback phenomenon and to develop a numerical simulation. Therefore, it is not part of the standard freecad install. For example, the exact hardness and temper of the metal will change the k factor of the bend, and this will have a small influence on the amount of material needed to achieve the correct flange lengths. The kfactor in sheet metal working is the ratio of the neutral axis to the material thickness. In most cases the bend radius would be the same for multiple bends and therefore the k factor is the same. This is a function of the bend angle, bend radius, thickness of the material, and a variable called the k factor.
Calculate k factor, bend allowance and y factor for sheet metal bending. Calculating bend allowance, bend deduction, and kfactor. So if the thickness of the sheet was a distance of t 1 mm and the location of the neutral axis was a distance of t 0. May 18, 2016 the k factor is empirically determined for a given material, material thickness, bend radius, and bending method. The k factor is the most important and elusive variable of bending, because it varies both as a function of the material and according to parameters such as angle and. The k factor depends on many factors including the material, the type of bending operation coining, bottoming, air bending, etc. Cut a sample sheet and measure its total flat length and sheet thickness in mm. Apr 25, 2018 kfactor a constant determined by dividing the thickness of the sheet by the location of the neutral axis, which is the part of sheet metal that does not change length. Bending is a common sheet metal operation used to create flanges, curls, and seems. Learn what a kfactor is in sheet metal forming, learn how kfactor is used, and learn how to calculate kfactor in this video. The yfactor is used, as far as i know, solely by ptcs proengineer, now known as creo elementspro. It allows you to anticipate the bend deduction for a large variety of angles without having to rely on a chart. The bend allowancebend deduction of the sheet metal specified in k factor by configuring and utilizing a sheet metal gauge table, we can speed up the process of selecting the correct wall thickness based on gauge value and selecting. Nov 30, 2018 learn what a k factor is in sheet metal forming, learn how k factor is used, and learn how to calculate k factor in this video.
Bending is defined as the plastic deformation of sheet metal along a straight line. The k factor is defined as the ratio between the material thickness t and the neutral fibre axis t, i. So for a very large radius bend where the neutral axis lies right in the center of the material, the kfactor would be exactly 0. Bend allowances vary based on the angle of the bend, the type and thickness of the material, and the method used to create the. After bending the sheet we need to do some measurements as shown in figure 2.
The k factor is used to calculate flat patterns because it is related to how much material is stretched during bending. In most cases the bend radius would be the same for multiple bends and therefore the kfactor is the same. Sheet metal is extremely handy for all kinds of jobs since its so easy to work with. Most frequently, expensive sheet metal bending tools, called brakes, are used to bend sheet metal, but you can also complete this task without one. The value of the kfactor should range between 0 0,5. Pdf factors affecting on springback in sheet metal bending.
Bending is a commonly used sheet metal shaping process in various sheet metal industrial products tekiner 2004. The k factor in sheet metal working is the ratio of the neutral axis to the material thickness. The kfactor depends on many factors including the material, the type of bending operation coining, bottoming, airbending, etc. One of the m ost important aspects o f good sheet metal formi ng manufacturing prac tice is the accurate. The main reason that i compared it ti the appearance ui is that it clearly has a standard library, you custom items, and also shows what is unique to the document. Where t is the distance from inside face to the neutral sheet and t is the sheet thickness figure 1. Solidworks sheet metal tools are relatively straight forward, but may not be clearly understood. In sheet metal, there is a powerful bend constant known as the kfactor. The bend allowancebend deduction of the sheet metal specified in kfactor by configuring and utilizing a. The kfactor is empirically determined for a given material, material thickness, bend radius, and bending method. K factor is a ratio that represents the location of the neutral axis with respect to the thickness of the sheet metal part and depends on material, thickness and bend radius. A few among the most common applications of sheet metal parts are as automobile and aircraft panels, housings, cabinets.
And you can see over here,weve got this bend allowance checkmark already turned on. The main reason that i compared it ti the appearance ui is that it clearly has a standard library, you custom items, and also shows what is. Apr 21, 2020 bend allowance is a measure of how much extra material is required to accommodate a bend in sheet metal. This is a basic guide to the main processes involved in sheet metal bending. The y and k factors affect how the part stretches when transitioning from a flat pattern to a finished piece so it is important to understand their values. A bending operation is employed to fabricate parts such as braces, brackets, supports, hinges, angles, frames, channel and other non. The kfactor is used to calculate flat patterns because it is related to how much material is stretched during bending. I had a question on k factors for our 3d modeling software. Even still, it can be pretty easy to mangle if you dont use the right technique. When sheet metal is bend, the inside bending surface is compressed. Sheet metal bending design tips, bend allowance, k. In sheet metal design, the kfactor is used to calculate how much sheet metal one needs to leave for the bend in order to achieve particular final dimensions. In this article we will discuss sheetmetal bend deduction, bend allowance, k factor, y factor and sheet metal flat pattern calculations.
Press brake bend allowance chart free technical charts. We do not design precision sheet metal equipment if there is any such thing but we use the same kfactor for a hem versus a 9045etc. When metal is bent the top section is going to undergo compression and the bottom section will be stretched. When you bend sheet metal, the neutral axis shifts toward the inside surface of the bend. Then input leg length a and b to get the flat size. Sheet metal k factor user modification i also thought about referencing the parameters ui, which would work well also. Bending calculations using kfactor, bend deduction, and bend. Figure 2 illustrates the sheet that is bent with the bend angle of 90 degrees.
How to set up sheet metal gauge tables engineers rule. Jun 06, 2017 figure 2 illustrates the sheet that is bent with the bend angle of 90 degrees. Kfactor is a ratio that represents the location of the neutral sheet with respect to the thickness of the sheet metal part. The value of the k factor should range between 0 0,5. The below chart is for even numbered gauges 8 through 24 and has a default k factor of. Mar 07, 2018 when you bend sheet metal, the neutral axis shifts toward the inside surface of the bend. Since the inside compression can not exceed the outside tension, the kfactor can never exceed. Jun 25, 2019 k factor is used to calculate bend allowance or deduction in sheet metal parts. How to use this kfactor calculator in sheet metal reverse engineering approach step1. The below chart is for even numbered gauges 8 through 24 and has a default kfactor of. Now, you may be thinking, where this k factor is used.
Pdf the study of design constants in sheet metal forming. For instance you have sm thickness 1mm and you look for a flange of 10mm that means efectively that your bendline should be in a distance from the edge between 8. Kfactor calculator for sheet metal bending smlease design. The fineart of sheet metal bending engineeringclicks. The online free fabrication calculator will help you calculate the k factor, y factor, bend allowance, bend deduction, flat size, neutral axis, arc length etc. Let me make it clear that it is a very important term used in sheet metal design. Most cad systems that have sheet metal design tools will allow you to input a k. The following equation relates the kfactor to the bend allowance. Pdf bend allowance constants for use in sheet metal forming. As far as solidworks goes, it seems i apply one kfactor for all sheet metal pieces when i convert a body into sheet metal.
When working in solidworks to create sheet metal designs, we will often need to know three important values. Kfactor is actually the ratio of the offset t of the neutral axis from the inside bend and the thickness of the sheet t when a piece of sheet metal is bent. The inside radii are based off of a standard air bend force chart. Therefore it is important to have the value correct in cad software. You can easily modify the material thickness, inside radius and k factor for each thickness at the top of each column.
Calculate k factor, bend allowance and y factor for sheet. Learning to accurately layout and bend sheetmetal is a very useful exercise. Bending calculations using kfactor, bend deduction, and. Bending sheet metal by hand is a manageable task if the piece of. We can calculate the leg length 1 and 2 as follows. What is the formula for the development length on sheet metal. I have idea to use sheet metal to avoid bend part option in standard modeling please imagine that i have curve which consists of 10 arcs, then i need to make 10 bending operations to get the wished shapethat is the reason why i am trying with sheet metals, but kfactor makes a problems with material extension. As long as you put the right bend deduction,bend allowance, or kfactor in to solidworks. So, basically, over here under the sheet metal folder,at the very top, right click,and click on edit. From there we can calculate the k factor and the bend deduction.
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