U.S. Patent Nos.
Frequently Asked Questions
Where and when should I use swing clamps?
Swing clamps are a logical choice where loading of the part is hampered by other styles of clamp. Swing clamps (as their names indicate) move out of the way for easy access to the load/unload area. They may be easily visualized by tool designers and the action emulates that of manual strap clamps.
Are there some applications where I need to avoid using swing clamps?
Yes, swing clamps should not be used when there are no fixed stops or hard locators into which the cutter force is transmitted. If swing clamps are oriented to hold vertically, horizontal cutter forces should be transmitted into solid stops that can easily absorb their energy. If forces are transmitted to swing clamps at 90° to the clamp action, all of the force is transmitted into the rotating mechanism. This may result in premature wear and early failure.
How do I size swing clamps?
First, calculate your cutter forces or climbing forces to be resisted. Then examine the direction of these forces. Determine how much of these forces will have to be held by the clamp. Size your clamp based on the estimated working pressure of your fixture. (We recommend using 200 bar to 275 bar (20 MPa-27,5 MPa) at this point to give you some additional capacity if required when your fixture is complete or processes change.)
I want the fastest possible action from my swing clamps. How do I do that and how fast can I get?
Look at the Clamp Time and Fluid Flow Rates chart to determine flow rates. A good rule of thumb, "If you see the clamp open, then see it closed, but don't see it move between, it moved in less than 1/16th second. That is always too fast" Finally, ask yourself; "To what good use will the operator put that extra fraction of a second?" If the answer is none, slow the clamp down.
I am planning to exceed the flow rating of your clamps, but I will be using low pressure. That's OK isn't it?
No. Excessive speed is excessive speed, regardless of pressure. Swinging an arm against a cam faster than intended is not recommended. It will shorten clamp life even at low pressures. We recommend not exceeding maximum flow rates.
My swing clamps don't all contact the part at the same time. Why?
Flow restrictions, excess fittings, long tubing runs and different springs can all cause swing clamps to swing at different times. Despite the appearance, they actually build to pressure at approximately the same time.
NOTE: Do not use this as a sequence valve.
My application calls for an arm about the size of a baseball bat, weighing 6.4 kg. How fast can I swing it?
VERY SLOWLY! Weight, like flow, can damage a swing clamp. If you must use an arm exceeding the weight of our standard or extended arm, slow it down. Heavy arms should be used on double acting clamps only, and swing speed must be restricted in both directions. Remember the length and pressure limitations from the charts provided.
I want to use a 2 kN swing clamp but need a 22 kN swing clamp arm for length. How do I fit this arm onto the clamp? What are my flow and pressure restrictions?
You will have to add to an extended arm or make a custom. We cannot supply an arm modified to these specifications. A reach of this distance is not recommended. If you must reach beyond the limits charted, please consult Vektek engineers for assistance.
I need to clamp over a work support. Are there any special precautions that I should take?
Yes, you will want to be sure that the clamp is sequenced to swing only after the support has built sufficient pressure to hold the force it is capable of generating and that they are properly sized. Sequencing is recommended only above 140 bar (14 MPa) using a Vektek sequence valve (other brands will not work). The recommended swing clamp to work support ratio is approximately 1:2 (5 kN swing clamp, 11 kN work support).
Installed on most Vektek swing clamps, the Arm Clocking feature will dramatically reduce the time it takes to change arms for maintenance, replacement or design set up. This innovation eliminates the need for expensive special swing clamps and moves cost effective user modifications to the clamp arms.
A drill point on each clamp standardizes arm location at a particular position. A second orientation drill point resides 180° out from that position. Access to the positioning feature is through the back or side of the arm, making modification a snap for users. Each arm position can have its own specification.
All dimensions are in mm.
Swing Clamp Swing Restrictors
Swing Restrictors add just one more element of flexibility when using Vektek Swing Clamps. Normally shipped with the swing angle set to 90˚, you can have swing restrictors added to your clamps to limit the the arm swing to 30˚, 45˚ or 60˚of rotation. Restrictors that are factory installed on new product will be specially marked to avoid intermingling clamps with varying swing angles in your shop. Contact your Vektek Customer Service specialist should you need swing angles greater than 90˚.
TC LP SC 33kN
ILMV150112 REV B
Clamp Time and Fluid Flow Rate Chart
ILMV150203 Rev A
- The above flows are maximum recommendations and clamp times are minimum recommendations.
- For upreach and double arms, use extended arm flows and times.
- The actual time to position the clamp will vary by custom arm configuration and may require customer testing in specific application to establish limits.
Arm Length and Pressure Limitations