Learn more about the victory tiebarless product line. Using torque to measure clamp force an inconvenient truth. Both axial and shear forces, acting individually, or simultaneously, can be taken into account, together with any residual clamp force that may be required to maintain a functional requirement such as gasket sealing. Engineering fundamentals of threaded fastener design and analysis. In order to keep the mold closed, this force must oppose the separating force, caused by the injection of molten plastic into the mold.
The clamping force on a bolt is defined as the compressive force a fastener exerts on a joint. Clamp force moldflow insight autodesk knowledge network. Modeling for accurate clamp force prediction fill analysis calculates the maximum clamp force required to keep the mold closed during filling. The clamping element can clamp different clamping rim heights due to the long clamping stroke of the double acting cylinder. Can you suggest the best way to calculate clamping force for milling amp drilling operations to select the proper clamp which data book can prefer to. Using torque to measure clamp force an inconvenient truth the traditional method for tightening fasteners is to turn the bolt head or nut using a torque wrench. To calculate preload force as a percentage of yield strength, use. It is easy to determine the clamping force and the corresponding deformation. Clamping force refers to the force applied to a mold by the clamping unit of the injection molding machine.
The main factor as to whether a bolted joint will sustain the applied forces is will the bolts generate sufficient clamp force or preload. The required clamping force can be calculated from the cavity pressure inside the mold and the shot projected area, on which this pressure is acting. Nov 30, 2014 homemade gauge to measure force applied by clamps these measurement are not necessarily scientifically accurate, but give an indication of differences. It is created to help the users to calculate the injection moulding parameters that involve in some processes. Therefore, for fea import piston clamp lever cad model in ansys static workbench and define contacts between piston, small pin and clamp lever respectively. Be cautious of the flow simulation analysis software you use, as it may only. This is integrated with the clamping force calculation. If the product of the clamping force and the coefficient of friction is greater than the applied slipping force, then friction prevents sliding between the surfaces and the net slipping force is zero. In this case twothird of the clamping force is applied to the workpiece. The elements are excluded from the clamp force calculation when you run a. The database created from the finite element analysis results. Clamp force propertymanager 2018 solidworks plastics help. How to calculate clamping force on a shaft coupler. But the user has to enter the detail required for selecting clamping element and the software module will give the necessary results is show in figure 7.
Please note that countryspecific content may not be available in your country. See table below for how much clamping force is available from manual clamp straps of various sizes with a 2to1 clampingforce ratio to compare with powerclamp forces. Homemade gauge to measure force applied by clamps these measurement are not necessarily scientifically accurate, but give an indication of differences. Some methods involve calculating clamping force by tightening the bolt by a predetermined angle and here pitch does matter. A simplified example appears below, with cutting force entirely horizontal, and.
With the forcecheck collet force gauge, the clamping forces on collets and hydraulic tool holders can be measured to obtain accurate machining specifications while fulfilling iso standard requirements. Regrettably, accurately determining the answer to this question is often glossed over during the design phase of clamping fixtures. It varies a little depending on bolt washer diameter. This calc simply determines if objects a and b are able to slide past each other. This fastener bolt torque calculator will estimate the unknown torque, diameter, axial force applied and coefficient of turning friction for the given conditions.
Clamp force moldflow flex autodesk knowledge network. F axial bolt force or load n, lb f torque reduction due to lubrication % note that standard dry torques are normally calculated to produce a tensile stress or axial force or clamp load in the bolt that equals to 70% of minimum tensile strength or 75% of proof strength. This userfriendly, nocost tool will provide you with a recommended solon torque calculation and help further assist you with your solon belleville spring and washer selections. Injection molding machine clamping force calculation. This amount of tightening, a rule of thumb, is suitable for. In my situation, i have to calculate the clamping force then choose a suitable type of injection molding machine which close to allowable clamping force of the machine.
Clamping force refers to the force applied to a mold by the clamping unit of an injection molding machine. Manually calculated clamp force is higher than clamp force result in. Pressure, does it use any safety factor x for calculation. Consult intrinsic devices for application specific.
Also remember that repeatable clamping pressures will help you achieve better accuracy. Bolted joints are often tightened to 75% to 80% of bolt proof load. The machine defined in the mold base definition dialog box is displayed with values for possible injection pressure and clamping force. Vise clamping force tightening your vise news desk. Modeling for accurate clamp force prediction moldflow insight 2018. Clamping force f n is the force pressing each brake pad against the disc. Click emx assembly emx tools calculate clamping force. The clamping force will be many times the force that is applied to the handle. To start viewing messages, select the forum that you want to visit from the selection below. This continues to be one of the questions most frequently asked of the vektorflo technical support team.
Hi, in moldflow for clamping force calculation f proj. Boltcalc bolted joint analysis software bolt science. How to calculate clamping force injection mold design. Force calculations for bolted joints machine design. Braking force f b is the tangential friction force acting between the brake pads and disc. General information and guidelines poweroperated clamping devices fspo fspz m. How to calculate clamping force for injection molding. Calculate clamp force on bike handlebar engineeringclicks. Design, development and analysis of clamping force of a. As we know clamping unit purpose is to keep mold closed against force when part injected with plastic material, because of that clamping force at least more than injection force, we can applied this clamp pressure both in injection machine with hydraulic or with mechanical toggle.
Clampingforce calculations can be quite complicated. The calculator below can be used to calculate the torque required to achieve a given axial bolt force or load. If you do not specify a clamp force direction, the software provides an estimate. The required clamping force can be calculated from the cavity pressure inside the mold and the shot. Can you suggest the best way to calculate clamping force for milling amp drilling operations to select the proper clamp which data book can prefer to get more accurate datas in metric. While the tool may be very accurate, measuring torque only measures how difficult it is to turn the bolt. Jun 11, 2012 the clamping force will be many times the force that is applied to the handle. Pressure lbin2 x projected area in2 what is projected area. Rather than evaluating the actual forces generated during machining and selecting clamps accordingly. How to calculate clamping force in fixture design carr lane. How to calculate injection moulding clamping force.
A clamping force that is too low will likely lead to inconsistent results or. Finally, the postyield zone begins with an inflection point at the end of the elastic range. See torque force design equations webpage and torque chart page for recommended fastener torque and equation data this fastener bolt torque calculator will estimate the unknown torque, diameter, axial force applied and coefficient of turning friction for the given conditions. Bolt torque, axial clamp force, bolt diameter calculator. You are now being redirected to our german subsidiary. Reset the clam in an undercentre position with the same angels. Regrettably, accurately determining the answer to this question is often glossed over. You can also calculate required clamping forces based on calculated cutting force. Empirical formula 1 clamping force t clamping force constant kp product projected area s cm cm kp experience value. Clamping force resisting momentd clamping force 17100 inlbs0. The interactive software module was developed for the purpose of calculating deformation of workpiece. Manual clamp force calculations are used as a rule of thumb and have a factor of safety to cover a variety of different geometries, materials, and process conditions. The clamping force, indicates the amount of force that the clamping unit can apply to the mold to keep it securely closed during the injection of the molten plastic, picture below shown injection machine from nissei with type nex80 80 ton formula. Excluding undercuts from clamp force calculation if a model contains undercuts or slides, the projected area calculation of the clamp force may be overpredicted.
It is difficult for the program to distinguish these special cases, so you may need to manually exclude undercuts from the clamp force calculation. Hi, im also facing the problem of determine the clamping force. Tech tips how much clamping force do i need to hold this part. This calculation is performed by the technical department at engel uk. Therefore, for fea import piston clamp lever cad model in ansys static workbench and define contacts.
Calculate molding clamp tonnage for plastic injection icomold. The bolted joint works by inducing an initial clamping force preload on the joint by threading the fastener into either a nut or into threads that have been tapped into one of. The program will allow for variations in the bolt clamp force or preload due to. Servohydraulic, hybrid and allelectric ranges available with clamping forces from 280 to 5000 kn.
Estimated fastener bolt clamp force torque calculator. This is assuming a static coefficient of friction of about 0. General information and guidelines poweroperated clamping. So if you look at the clamping bracket now to get equilibrium we have 6730 x 51. In the real world when clamping force is important,a hydraulic tensioner pulls the studbolt and then the nut is tightened. The bolted joint works by inducing an initial clamping force preload on the joint by threading the fastener into either a nut or into threads that have been tapped into one of the parts. Tonnage calculations impact on cost control kaysun corporation. Or speak to one of our team about the benefits of this innovative technology. Calculating the clamping force for machining how much clamping force do i need to hold this part. For ordinary applications like car wheel lugs or headbolts, the manufacturer has the experience to know the torque levels to apply. Most manual clamp force calculations dont take into account specific factors such as actual cavity injection pressure. Clamping force required mechanical engineering general.
Too much clamping force could damage parts with thin wall sections. The primary components of a bolted joint include the threaded fastener as well as the parts to be joined together the clamped parts. If you need to accommodate large and complex mould tools then engels tiebarless technology is the best solution. Both axial and shear forces, acting individually, or simultaneously, can be taken into account, together with. There are variables that affect the clamping force calculation, like the material type lowflow versus highflow plastic, and the depth of the part. The clamp tonnage in moldflow is the clamp force required for a specific geometry, material, and injection pressure. Determining the clamping force on a tube physics forums. The software is developed and design by using microsoft visual. In this project, mould calculation software is developed and design.
It is a good practice to become familiar with your vises clamping forces. Therefore, for fea import piston clamp lever cad model in. To calculate clamping forces by fea method for hydraulic pressure of 3. Use this calculate clamping force to assess the compatibility of a mold base with a specific injection machine. Manually calculated clamp force is higher than clamp force. F pl % yld s ty a t where % yld is the preload percent of yield, s ty is the yield strength, and a t it the tensile stress area. A fine thread will all else being equal be stronger than a coarse one. For any application there is a minimum clamping force required to prevent joint failure. Unilok clamping force calculation intrinsic devices. The tensile stress is in the neighborhood of 46,000 psi without considering buckling. In order to optimize our website and to ensure continuous improvements, this website is using cookies. Seems quite large to me, but maybe this is too simplistic. Engineering fundamentals of threaded fastener design and. You will have to register or login see top or bottom of page before you can post a message or view images.
Use our new torque calculator web tool below to determine a calculated torque value based on inputs relative to bolt type, size, lubricantcondition and load. Instead of using an injection molding machine tonnage calculator, many. Apr 20, 2012 the clamping force is proportional to the projected area of the moulding and runner, and must be opposed by the clamping force. Before restarting a serial machining operation and in between the maintenance intervals the clamping force should be checked by means of a load cell.
When clamping single part, a better placement is with onethird of strap length between the fastener and workpiece and twothirds between the fastener and heel support. By using this website, you agree to the use of cookies. This is can be dependent on a number of factors, but is largely a function of the preload force, the force exerted in compressing the bolt, and the tension force, the force exerted in pulling the bolt apart. By my calculation 900lbf is nearly enough to cause the bolted plate to fail on the tension side, and thats without considering that there may be an impact component to the force in the real world. Clamp force requirements injection moulding plastikcity. How to calculate a bolts clamping force it still runs. The clamping force is required to prevent joint movement being caused as a result of axial andor shear forces.
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