Ordering Gradient Column Floats
The price for a standard float with a density between 800 and 1599 kg/m3 is £96.60GBP.
The price for a standard float with a density less than 800 kg/m3, or greater than 1600 kg/m3, is £121.30GBP.
Sets of floats with a step size ≤5 kg/m3 may incurr an additional charge.
Discounts are not normally given for orders of fewer than 50 floats. Carriage is charged at cost.
We also offer a recalibration service for customers who already have their own floats. It is vital that floats are recalibrated if they may have been damaged or abraded in any way. Failure to recalibrate damaged floats may severly compromise the accuracy of your measurements.
Recalibration is £89.20GBP per float.
Standard Floats — Tolerance and Uncertainty
The tolerance of a float is defined as the acceptable difference between the density of float as specified by the customer, and the actual calibrated density of the float.
For a single float, ordered on its own, the standard tolerance is ±0.5 kg/m3.
For a set of floats, the standard tolerance is ±10% of the difference in density between adjacent floats.
The standard uncertainty of the measurement is ±0.15 kg/m3 at k=2.
In addition to our standard floats, we are also able to offer floats with a tolerance of 0.1kg/m3. Making a float with a smaller tolerance involves more work, and therefore costs more than a float with a wider tolerance. Prices are available on request. Please contact us for details.
It is important to know what tolerance is acceptable. Buying a float with a smaller tolerance than you really need is a waste of your money. If you are unsure as to what level of tolerance you require, please contact us to discuss your requirements.
We are also able to offer enhanced accuracy in terms of measurement uncertainty. Our best Calibration and Measurement Capability (CMC) is ±0.1 kg/m3 at k=2.
Prices for floats with lower measurement uncertainties are available on request. Again, please contact us for details.
If you are unsure as to what level of uncertainty you require, please contact us to discuss your requirements.
How to Order Gradient Column Floats
You can order a set of floats covering a density range, for example 9 floats covering the range 860 to 950 kg/m3 , and we will adjust the floats so that their densities are more or less evenly spaced across the range.
Alternatively, you can order by specifying the densities you want.
Each float has a unique identification number inside the glass, and is supplied with a ISO 17025 accredited calibration certificate, quoting its density and mass.