What is the difference between load cells of "OAP" and "Normal" quality?
There are two categories of quality in the production of KELI load cells: "OAP" and "Normal". We will consider the difference between these qualities on the example of KELI SQB-A load cells:
The load cells are exactly the same in terms of geometric dimensions, RCC, input and output resistance, accuracy class, number of test intervals, operating temperature range, insulation resistance, permissible overload, and they are completely interchangeable with each other.
Still, these two qualities, "OAP" and "Normal," have a number of differences.
The first and most noticeable external difference is the color of the load cell cable. In the production of load cells of "Normal" quality, a standard black strain gauge cable with PVC insulation is used.
In the production of load cells of "OAP" quality, a bright orange cable in polyurethane insulation is used, which has heat and frost resistance. Impurities are added to the insulation material that are not suitable for rodents.
The second and most important difference is the difference in the material used in the production of load cells.
For the "Normal" quality, 42CrMo alloy steel is used, the chemical composition of the steel is shown in the table below:
C | Si | Mn | Cr | Mo | P | S |
|---|---|---|---|---|---|---|
0.38-0.43 | до 0.4 | 0.6-0.9 | 0.9-1.2 | 0.15-0.3 | ≤0.035 | ≤0.035 |
For the quality of the OAP, 40CrNiMoA alloy steel is used.
Class A steel undergoes a double electroslag remelting process to minimize the amount of S and P impurities; the chemical composition of the steel is shown in the table below:
C | Si | Mn | Ni | Cr | Mo | Cu | P | S |
|---|---|---|---|---|---|---|---|---|
0.35-0.42 | 0.17-0.37 | 0.3-0.6 | 1.35-1.75 | 1.25-1.65 | 0.2-0.3 | ≤0.3 | ≤0.025 | ≤0.025 |
