Specified in ISO 4200, EN10220 or DIN2448, the specified size of steel pipe refers to the length, outside diameter, inside diameter and wall thickness of the steel pipe. The range size of steel is an effective measure to save materials. Today we will discuss the length of steel pipe. Delivery length is also known as customer required length or contract length. Steel pipe manufacturers or suppliers can supply according to standard length. The legal units of measurement for the length of steel pipe are “m”, ” cm” and “mm”.
Indefinite length refers to the length of steel pipe in the standard range and does not require fixed length, also known as the usual length. The steel pipes delivered by indefinite scale shall be delivered within the specified length range. For example, the standard of structural pipes stipulates: the length of hot-rolled (extruded and expanded) steel pipes is 3000mm ~ 12000mm; Cold drawn (rolled) steel tubes with a length of 2000mm ~ 10500mm can be delivered within this range.
That is steel pipes are cut to a fixed length according to the order requirements. The fixed length shall be within the normal length range required in the contract. The delivered metal materials shall have the length specified by the buyer in the order contract. However, it is impossible to determine the absolute length in the actual processing, so the standard provides the allowable positive deviation value of the length. For example, it is noted in the contract that the steel pipe shall be delivered with a fixed length of 5m, and more or less than 5m is unqualified. However, in fact, it is impossible to deliver the finished product with a length of 5m, so positive deviation is allowed except the negative deviation. Steel pipe production rate of fixed length greatly reduced than the usual length of the of finished products, manufacturers will generally increase the price of 10% at the base price.
The fixed length required by the order is cut into integral multiples called multiple lengths, which should be within the normal length range. Steel pipes delivered at multiple lengths must be of the length (single feet) or integer multiples (saws is added) specified in the order contract. For example, in the order contract, the buyer requires a single foot length of 2m, then a double foot length of 4m, or 3 times the length of 6m, and a notch margin for each single foot length, which specified in the standard. For example, the outer diameter ≤159mm, the margin of incision is 5 ~ 10mm; The outer diameter > 159mm is 10 ~ 15mm. If there is no multiple length deviation and cutting allowance in the standard, it shall be negotiated by both parties and indicated in the contract. Double length scale will greatly reduce the rate of steel pipe manufacturers as long as fixed length.
The range length is generally contained within the usual length and shall be indicated in the contract when the buyer requests a fixed length of the range. For example, the length is usually 3000 ~ 12000mm, while the range length is 6000 ~ 8000mm or 8000 ~ 10000mm.