We can calculate the leg length 1 and 2 as follows. Forming processes in manufacture of an access cover and control. You only have to insert interior angle, flange lengths, k factor, inside radius, and material thickness. Apr 30, 2011 download k factor lessthan90degreebends. Sheet metal k factors but if both parts are identical makeup, i. You will need to know your material thickness mt, the bend angle b free fabrication calculator will help you calculate the kfactor, yfactor, bend allowance, bend deduction, flat size, neutral axis, arc length etc. The bend allowancebend deduction of the sheet metal specified in kfactor 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. You will probably have to start with the supplier of your sheet stock as there are a number of items which effects the kfactor, including not only the material thickness, but the yieldpoint and other physical properties of the metal. In reality, how a real metal part will stretch as it bends depends on a number of physical factors tooling, material homogeneity etc. In this article we will discuss sheetmetal bend deduction, bend allowance, k factor, y factor and sheet metal flat pattern calculations. There are many other tools that can be used with this software. The k factor is defined as the ratio between the material thickness t and the neutral fibre axis t, i.
Calculate k factor, bend allowance and y factor for sheet metal. Bend allowance can be calculated using manual experiment. Sep 28, 2015 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. Kfactor is a ratio that represents the location of the neutral sheet with respect to the thickness of the sheet metal part. Determining the kfactor for sheet metal 12052008 9. 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 k factor makes a problems with material extension. The global sheet metal market size was valued at usd 265. 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.
K factor is a ratio that represents the location of the neutral sheet with respect to the thickness of the sheet metal part. Dec 27, 2016 when working in solidworks to create sheet metal designs, we will often need to know three important values. The kfactor approximations given below are more likely to be accurate for air bending. After bending the sheet we need to do some measurements as shown in figure 2. Mar 07, 2018 when you bend sheet metal, the neutral axis shifts toward the inside surface of the bend. Relationship between bend deduction, bend allowance, and k factor. Bending a known length of sheet metal is easy, but to calculate the bend. Possible values for kfactor standard is ansi or din. May 17, 2020 possible values for k factor standard is ansi or din. Figure 2 illustrates the sheet that is bent with the bend angle of 90 degrees. 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. It is used to calculate sheet metal flat length flatpattern.
With this free online tool you can calculate the k factor, a fundamental parameter used to calculate sheet metal elongation according to your bending setting. I had a question on kfactors for our 3d modeling software. So, basically, over here under the sheet metal folder,at the very top, right click,and click on edit feature. Pdf bend allowance constants for use in sheet metal forming. 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. Cut a sample sheet and measure its total flat length and sheet thickness in mm. To use the sheet metal extension, first you need to install the latest version of freecad 0. The solidworks application also comes with a k factor bend table in microsoft excel format. Let me make it clear that it is a very important term used in sheet metal design.
The k factor depends on many factors including the material, the type of bending operation coining, bottoming, airbending, etc. Sep 01, 2012 anna is correct in stating that your own k factor will need to be developed through testing. The online free fabrication calculator will help you calculate the kfactor, yfactor, bend allowance, bend deduction, flat size, neutral axis, arc length etc. And you can see over here,weve got this bend allowance checkmark already turned on.
Bending calculations using kfactor, bend deduction, and bend. It is a kfactor calculator developed by the new zealand company knac solutions. May 29, 20 so for a very large radius bend where the neutral axis lies right in the center of the material, the k factor would be exactly 0. When metal is bent the top section is going to undergo compression. Therefore if a kfactor addin is running the sheet metal kfactor will update automatically whenever the thickness or bend radius is changed. You will probably have to start with the supplier of your sheet stock as there are a number of items which effects the k factor, including not only the material thickness, but the yieldpoint and other physical properties of the metal. Weve even developed our own inhouse tools, spreadsheets, or other cheat sheets to get close enough because no one wants to do the math each time. The inside radii are based off of a standard air bend force chart.
Best way to calculate k factor in sheet metal is by reverse engineering. The values of the setback, bend allowance, and bend deduction can be calculated from the sheet thickness, bend radius, bend angle, and kfactor. Sheet metal kfactors but if both parts are identical makeup, i. This change in sheet length depends on the position of neutral axis or kfactor. Calculate k factor, bend allowance and y factor for sheet metal bending. Press brake bend allowance chart free technical charts. It is our standard practice to lay out our composite cutandfold panels using the using the sheet metal feature with the k factor set to. When you select kfactor as the bend allowance, you can specify a kfactor bend table. Pdf on jul 5, 2006, karachalios and others published the study of design constants in sheet metal forming find, read and cite all the research you.
Our solidworks experts can setup your environment so that your team uses a comprehensive set of. Mathematically k factor value is equal to the ratio of position of neutral axis and sheet thickness. Analyzing the kfactor in sheet metal bending the fabricator. Bend allowance is a term which describes how much material is needed.
Bend the sheet to 90 degrees and measure length a and b. All sheet metal workers know the importance of an accurate kfactor or bend allowance when it comes to design. The line where the transition from compression to stretching occurs is called the neutral axis. When you bend sheet metal, the neutral axis shifts toward the inside surface of the bend. In this article we will discuss sheetmetal bend deduction, bend allowance, kfactor, yfactor and sheet metal flat pattern calculations. When metal is bent the top section is going to undergo compression and the bottom section will be stretched. When working in solidworks to create sheet metal designs, we will often need to know three important values. 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. 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. Determining the kfactor for sheet metal cr4 discussion thread. K factor 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 in sheet metal working is the ratio of the neutral axis to the material thickness.
Calculate k factor, bend allowance and y factor for sheet. If you noticed there is no library of material for the k factor and you were not prompted for the bend radius. Kfactor calculator for sheet metal bending smlease design. The bend deduction is the amount the sheet metal will stretch when bent as measured from.
Registered users 83,439 forums 1 topics 45,395 replies 217 topic tags 4,401. Sheet metal is one of the common building materials used across construction sector for various applications. From there we can calculate the kfactor and the bend deduction. The kfactor is the ratio of the neutral axis location t to the material thickness mt. How to set up sheet metal gauge tables engineers rule. Sheet metal bending design tips, bend allowance, k factor, etc. 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. I had a question on k factors for our 3d modeling software. The k factor can be customized by excel spreadsheets and the bend radius can be set after the part has thickness by editing the sheet metal feature in the browser bar. The mold line lengths are the distances measured to the outside mold line and are equal to the flange lengths plus the setback. A printable pdf version of this information is available here. You will need to know your material thickness mt, the bend angle b k factor k. I have been working in precision sheet metal for 40 years, no one k factor will work everywhere. My assembly consists of a flat part with 1 hem, and a second part that has two bends and a hem.
You can easily modify the material thickness, inside radius and k factor for each thickness at the top of each column. The k factor in sheet metal is the ratio of thickness to the location of the neutral line in the metal cross section. Bend deduction explained with formula and calculator. In sheet metal design, the k factor is used to calculate how much sheet metal one needs to leave for the bend in order to achieve particular final dimensions. 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. Miter flange, loftedbend, corner controls, sheet metal gusset and rip are all very common tools that can make life easier for the designer. You just have to collect some required data like kfactor, sheet metal thickness, bend angle and inside radius of the bend. Prosheetmetal will subtract from the actual length of the material to compensate for the elasticity. The bend deduction formula takes into account the geometries of bending and the properties of your metal to determine the bend deduction. As sheet metal parts are flattened or formed if you start with a flat state, prosheetmetal utilizes a y factor to allow for the fact that metal is elastic and stretches as it bends.
Jun 25, 2019 mathematically k factor is equal to position of neutral axis divided by sheet thickness. The material thickness will be measured in decimal form, not by the gauge number. Anna is correct in stating that your own k factor will need to be developed through testing. The kfactor in sheet metal working is the ratio of the neutral axis to the material thickness. Autodesk inventor kfactor sheet metal cadline community.
Sheet metal market size, analysis global industry growth. In inventor this ratio determines the final size of the unfolded sheet metal part. The kfactor allows you to calculate the bend allowance, the outside setback, the bend. Bend deduction can be easily calculated if you have a formula for it. The k factor, a fictional tv show within harry hills tv burp. Kfactors, yfactors, and press brake bending precision. Calculating bend allowance, bend deduction, and kfactor.
Mathematically k factor is equal to position of neutral axis divided by sheet thickness. Kfactor sheet metal, the ratio of location of the neutral line to the material thickness. As long as you put the right bend deduction,bend allowance, or kfactor in to solidworks. This change in sheet length depends on the position of neutral axis or k factor. My assembly consists of a flat part with 1 hem, and a. When sheet metal is bend, the inside bending surface is compressed. Bending is a manufacturing process that produces a vshape, ushape, or channel shape. The below chart is for even numbered gauges 8 through 24 and has a default k factor of. The k factor is the ratio of the neutral axis location t to the material thickness mt. How to use this k factor calculator in sheet metal reverse engineering approach step1. Value of k factor depends on material, sheet thickness, inside bend radius and machine used. Most cad systems that have sheet metal design tools will allow you to input a k factor that the software uses to calculate the unfolding to give an accurate blank, or flat pattern. Use unfold task panel to assign the material sheet. 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.
The kfactor is fundamental to designing precise sheet metal products. Jun 06, 2017 figure 2 illustrates the sheet that is bent with the bend angle of 90 degrees. Often bend allowances are calculated for a sheet metal part and used to make costly. Fabrication calculator for kfactor, yfactor, bend allowance. Now, you may be thinking, where this k factor is used. The solidworks application also comes with a kfactor bend table in microsoft excel format. 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.
It may work here and there as demonstrated by steven smith. Most sheet metal shops will produce their own bend tables by physically bending test pieces to specified angles and taking 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. Please note the bending of sample part is done in the same manner as we are planning for production. When you select k factor as the bend allowance, you can specify a k factor bend table. Pdf the study of design constants in sheet metal forming. Aug 27, 2019 we will learn base flange, edge flange, flatten the parts, how to save as 2d drawing for autocad use, and appearance in solidworks sheet metal. We use solidworks to model these parts currently but have started migrating to v5. Sheet metal k factor user modification i also thought about referencing the parameters ui, which would work well also. Folded sheet metal, with bottom added, after correction. From there we can calculate the k factor and the bend deduction. Most cad systems that have sheet metal design tools will allow you to input a kfactor that the software uses to calculate the unfolding to give an accurate blank, or flat pattern.
1458 205 786 1017 1328 1313 1262 1116 1471 847 407 1550 373 358 629 1368 1006 279 844 613 245 1158 566 1282 57 461 158 184 695 1526 1231 517 1137 182 1374 577 130 1283