As a Design Engineer or User, you should know about Delta Star "Curvback" Clamp Design.
Delta-Star "Curvback" clamps insure a heavy uniform pressure over the entire clamped surface, and at the same time automatically indicate when the clamps have been sufficiently tightened to secure maximum pressure without bending beyond their elastic limit.With ordinary flat back clamps, pressure is concentrated at the edges and there is nothing to indicate when maximum pressure is reached. Usually the clamps are tightened until they bow up in the middle and are stretched beyond their elastic limit. The danger of this condition is readily apparent as further stretching of the clamp may take place either due to fatigue or thermal expansion and contraction.
The latter condition is particularly apt to occur as uneven pressure will result in excessive current at the edges and no current at the middle of the joint, causing heating of the joint during peak load, with periodic expansion and contraction.
The "Curvback" clamp is superior to the flat back type in five essential features.
Due to the curvature of the clamp back, pressure is first applied at the middle of the bus connection.
As the bolts are tightened, the clamps stretch, exerting an even pressure over the entire surface clear to the edges.
When the edges of the "Curvback" clamps firmly touch the copper bus, its serves as an automatic indication that maximum pressure has been secured.
"Curvback" clamps retain their full elasticity as the clamp curvature is such that at no time does the fiber stress reach the elastic limit.
The possibility of the pressure lessening due to fatigue of the metal, thermal expansion and contraction is reduced to a minimum.
Go to product catalog Section "A"
Bar To Tube, Cable or Bar Connectors
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