Custom Stainless Steel Pipe 304 Stainless Steel Pipe Hollow Stainless Steel Pipe Bright Stainless Steel Capillary

size
A. Nominal size: the nominal size stipulated in the standard, the ideal size desired by users and manufacturers, and the order size indicated in the contract.
B. Actual size: the actual size obtained in the production process, which is usually greater than or less than the nominal size. This phenomenon of greater or less than the nominal size is called deviation.
C, meter weight: weight per meter =0.02466* wall thickness * (outer diameter - wall thickness)
Deviation and tolerance
A. Deviation: in the production process, because the actual size is difficult to meet the requirements of the nominal size, that is, often greater than or less than the nominal size, so the standard stipulates that there is A difference between the actual size and the nominal size. A positive difference is called a positive bias, and a negative difference is called a negative bias.
B. Tolerance: the absolute sum of positive and negative deviation values specified in the standard is called tolerance, also called "tolerance zone".
Deviation is directional, that is, "positive" or "negative"; Tolerances are non-directional, so it is wrong to call the value of the deviation a "positive tolerance" or a "negative tolerance".
The length of delivery
Delivery length is also called customer required length or contract length. The standard has the following provisions on delivery length:
A, ordinary length (also known as irregular length) : where the length is within the standard length range and there is no fixed length requirements, are called ordinary length. For example, structural pipe standards: hot rolled (extruded, expanded) steel pipe 3000mm ~ 12000mm; Cold-drawn (rolled) steel pipe 2000mm ~ 10500mm.
B. Fixed length: the fixed length shall be within the normal length range and is a fixed length specified in the contract. But in practice, it is impossible to cut absolute length, so the standard stipulates the allowable positive deviation value for the length of definite length.
The structural pipe standard is:
The yield of fixed length pipe decreases more than that of normal length pipe, so it is reasonable for the manufacturer to raise the price. Add price range each enterprise is not consistent, add price 10% or so on base price foundation commonly.
C. Length of multiples: the length of multiples shall be within the normal length range, and the single length and the multiple of the total length shall be indicated in the contract (e.g. 3000mm×3, i.e. 3000mm 3x, with a total length of 9000mm). In practice, the allowable positive deviation of 20mm should be added to the total length, plus the incision allowance should be left for each single ruler length. Take the structural pipe as an example, the specified incision allowance: outer diameter ≤159mm is 5 ~ 10mm; Outer diameter >159mm is 10 ~ 15mm.
If there is no length deviation and cutting allowance in the standard, it shall be indicated in the contract through negotiation between the supply and demand parties. Double ruler length is the same as fixed ruler length, which will greatly reduce the yield of production enterprises. Therefore, it is reasonable for the production enterprises to raise the price, which is basically the same as the fixed ruler length.
D. Range length: the range length is within the usual range. If the user requires a fixed range length, it shall be indicated in the contract.
For example, the length ranges from 3000 mm to 12000mm, and the length ranges from 6000 mm to 8000mm or 8000mm to 10000mm.
It can be seen that the range length is more relaxed than fixed length and multiple length, but it is much stricter than the usual length, which will also reduce the yield of production enterprises. Because this production enterprise puts forward add price is reasonable, its add price range is in base price commonly add price 4% left and right sides.