What is the National Standard Tolerance for 5mm Thick Stainless Steel Plate and What is the Actual Thickness?
According to the national standard, the actual thickness of a 5mm thick stainless steel plate is typically less than 5mm and more accurately falls within a range of 4.5mm to 5.2mm.
GB/T24511-2017, the national standard for Stainless Steel and Heat Resisting Steel Plates and Strips for Pressure Equipment, provides specifications for the thickness error range of 5mm stainless steel plates. These plates can be divided into hot-rolled steel plates and strips, or cold-rolled steel plates and strips.
The error of 5mm of the non inductive steel plate is as follows:
Allowable thickness deviation of hot rolled steel plate and strip
According to national standard (G5/T24,511-2017)
| National standard for actual thickness of 5mm thick stainless steel plate | Accuracy class | Width range (mm) | |||
| ≤1200 | >1200~1500 | >1500~1800 | >1800~2100 | ||
| PT.A | +0.31 -0.30 |
+0.33 -0.30 |
+0.36 -0.30 |
+0.38 -0.30 |
|
| PT.B | ±0.28 | ±0.30 | +0.33 -0.30 |
+0.35 -0.30 |
|
Note:
- PT. A refers to ordinary precision, while PT. B refers to higher precision.
- For instance, according to PT. A, the tolerance range for a 5mm thick hot-rolled stainless steel plate with a width of 1.5 meters should be between 4.7mm and 5.33mm. According to PT. B, the tolerance range should be between 4.7mm and 5.3mm.
Allowable thickness deviation of cold rolled steel plate and strip
According to national standard GB/T24511-2017
| National standard for actual thickness of 5mm thick stainless steel plate | Width range (mm) | |||
| ≤1000 | >1000~1300 | >1300~2100 | ||
| Accuracy | ±0.14 | ±0.15 | ±0.15 | |
2. According to GB/T4237-2015 Hot Rolled Stainless Steel Plate and Strip, 5mm stainless steel plate can be divided into thick steel plate, steel strip and coiled steel plate, as follows:
Allowable thickness deviation of thick steel plate
According to the national standard GB/T4237-2015
| 5mm thick stainless steel plate | Accuracy class | Width range (mm) | ||||
|---|---|---|---|---|---|---|
| 1000 | >1000~1500 | >1500~2000 | >2000~2500 | >2500~4800 | ||
| National standard for actual thickness | PT.A | ±0.31 | ±0.33 | ±0.36 | ±0.41 | ±0.65 |
| PT.B | ±0.28 | ±0.30 | ±0.34 | ±0.36 | ||
Note:
- PT. A refers to ordinary precision and PT. B refers to higher precision, in compliance with GB/T4237-2015.
- As an example, a 5mm thick hot-rolled stainless steel plate with a width of 2 meters should have a thickness range of 4.64mm to 5.36mm according to PT. A requirements, and a thickness range of 4.66mm to 5.34mm according to PT. B requirements.
Allowable thickness deviation of steel strip and rolled steel plate
According to national standard GB/T4237-2015
| National standard for actual thickness of 5mm thick stainless steel strip | Accuracy class | Width range (mm) | |||
| 1200 | >1200~1500 | >1500~1800 | 1800~2500 | ||
| PT.A | ±0.33 | ±0.33 | ±0.36 | ±0.38 | |
| PT.B | ±0.31 | ±0.30 | ±0.33 | ±0.35 | |
Note:
- PT. A refers to ordinary precision and PT. B refers to higher precision, both in accordance with GB/T4237-2015.
- As an example, a 5mm thick hot-rolled stainless steel strip with a width of 1.5 meters should have a thickness range of 4.67mm to 5.33mm according to PT. A requirements, and a thickness range of 4.7mm to 5.3mm according to PT. B requirements.
- GB/T3280-2015, the national standard for Cold Rolled Stainless Steel Plates and Strips, divides 5mm stainless steel plates into two categories: steel strips and rolled steel plates.
Allowable thickness deviation of wide steel strip and rolled steel plate
According to national standard GB/T3280-2015
| National standard for actual thickness of 5mm thick stainless steel plate and strip | Width range (mm) | ||
| <1250 | 1250-2100 | ||
| Accuracy requirements | ±0.4 | ±0.45 | |
Note:
- Based on GB/T3280-2015, the national standard for Cold Rolled Stainless Steel Plates and Strips.
- For instance, the national standard tolerance for a 5mm thick cold-rolled wide stainless steel strip with a width of 1.5 meters, a rolled steel plate, a longitudinal wide steel strip, or a rolled steel strip should be between 4.55mm and 5.45mm.
Example: What is the National Standard Tolerance for 5mm Thick 304 Plate?
When the width of the steel plate is 1500mm, the standard deviation of 5mm thick hot-rolled steel plate should be within -0.3mm, meaning the thickness should be no less than 4.7mm, in accordance with GB/T24511-2017, the national standard for Stainless Steel and Heat Resistant Steel Plates and Strips for Pressure Equipment.
For a 5mm thick cold-rolled steel plate with a width of 1500mm, the standard deviation should be within -0.15mm, meaning the thickness should be no less than 4.85mm. This is also in compliance with GB/T24511-2017.
It is important to note that the actual thickness of a 5mm thick steel plate should conform to the tolerance provisions specified by the relevant national standards, as outlined above.
