Length, width, height, diameter, radius, inner diameter, outer diameter and wall thickness of steel. The legal measurement unit of steel length is meter (m), centimeter (CM) and millimeter (mm). In current practice, it is also expressed in inches (″),
but it is not a legal unit of measurement.
What do you know about the length and size of steel?
1. Range and size of steel
Specifying the range and size of steel is an effective measure to save materials. Range sizing means that the length or length by width is not less than a certain size, or the length and length by width are delivered within the size range from how much to how much. The production unit can produce and supply according to the size requirements.
2. Indefinite length (normal length)
If the product size (length or width) is within the range specified in the standard and no fixed size is required, it is called indefinite ruler. Indefinite length is also called normal length (full length). Metal materials delivered to varying lengths can be delivered within the specified length. For example, if the length of ordinary round steel not more than 25mm is usually specified as 4 ~ 10m, the round steel with the length within this range can be delivered.
Cut into fixed sizes according to the order requirements is called fixed length. When delivering according to the fixed length, the delivered metal materials must have the length specified by the demander in the order contract. For example, if it is stated in the contract that the goods shall be delivered according to the fixed length of 5m, the materials delivered must be 5m long, and those shorter than 5m or longer than 5m are unqualified. However, in fact, the delivery cannot be 5m long, so it is stipulated that positive deviation is allowed and negative deviation is not allowed.
4. Double ruler
Cut into integral multiples according to the fixed size required by the order is called multiple ruler. When delivering by multiple length, the length of the delivered metal material must be an integral multiple of the length (called single length) specified by the demander in the order contract (plus sawing). For example, if the demander requires the length of a single ruler to be 2m in the order contract, the length is 4m when it is cut into double ruler and 6m when it is cut into three times ruler, and one or two saw cuts are added respectively.
The sawing amount is specified in the standard. Only positive deviation is allowed, and negative deviation is not allowed during delivery of multiple lengths.
5. Short ruler
If the length is less than the lower limit of indefinite length specified in the standard, but not less than the allowable minimum length, it is called short length. For example, it is stipulated in the standard for water and gas transmission steel pipes that 10% of 2-4m long short steel pipes (calculated by the number of pipes) are allowed in each batch. 4m is the lower limit of indefinite length, and the shortest allowable length is 2m.