Tallyrand Measuring Wheels
Horizontal Measuring Wheels
Pipe Mill Measuring Wheels
Vertical Measuring Wheels
Rollforming Measuring Wheels
A great number of measuring wheel assembly designs have evolved over the years, since a design suitable for one mill frequently was not good enough for another.
The most basic design consists of a single wheel, spring loaded against the tube. A hand wheel can be added for load adjustment. On some designs, a backup wheel is added to provide support and prevent deflection of the tube.
Air cylinder operated wheel (In Stock)
The air cylinder-operated wheel is an improvement over the basic design. Load can be varied with a regulator. For setup, the assembly can be opened and closed with a switch. Again, a backup wheel is sometimes included.
Many designs have the wheels moving in a vertical plane which necessitate some sort of counterbalance to avoid bending the tube. A design where both the measuring and backup wheels move in a horizontal plane overcomes the counterbalance problem. Both wheels can be loaded with equal area cylinders having the same air pressure on each. The wheels will follow the tube as the mill operator adjusts the straightening passes.
Typical repetitive accuracy on a measuring wheel is limited to about .002 inch/foot. The following conditions apply for accurate measurement.
· The wheel must be aligned to tube travel.
· Any visible groove in the wheel is enough to cause inaccuracy. Wheels coated with tungsten carbide or titanium nitride will wear longer. Wheels should be reground whenever worn. The wheel must, of course, be thoroughly hardened to make this possible.
· In some applications, particularly small-diameter tube, wheel inertia must be kept to a minimum.
· In the case of slippage due to coolant or lubricant, a knurled or sand-blast finished wheel will sometimes provide better accuracy.
· If the tube is moving laterally to the wheel surface or twisting, this condition must be corrected in order to achieve good accuracy.