Steel length dimension

The length of steel is the most basic size of all kinds of steel, which refers to the length of steel, width, height, diameter, radius, inner diameter, outer diameter and wall thickness. The legal units of measurement for the length of steel are meters (m), centimeters (cm), millimeters (mm). In the current custom, inch (") is also used, but it is not a legal unit of measurement.

1. Steel range size

Specifying the range size of steel is an effective measure to save materials. Range measurement means that the length or length by width is not less than a certain size, or the length, length by width is delivered from how many to how many dimensions. The production unit can produce and supply according to the size requirements.

2. Variable size (usually length) Where the product size (length or width) is within the scope of the standard provisions, but does not require a fixed size called variable size. The variable length is also called the usual length (ruler). Metal materials delivered by variable length, as long as they are delivered within the specified length range. For example, ordinary round steel of no more than 25mm, whose usual length is stipulated to be 4 ~ 10m, can be delivered with round steel in this range.

3. The size cut into a fixed size according to the order requirements is called the size. When delivery is made to a fixed length, the metal materials to be delivered must have the length specified by the buyer in the order contract. For example, if the contract states that the delivery is at a fixed length of 5m, the materials delivered must be all 5m long, and any shorter or longer than 5m is unqualified. But in fact, the delivery can not be 5m long, so it is allowed to have a positive deviation, but not allowed to have a negative deviation.

4. Double the size

According to the fixed size required by the order cut into an integral multiple called multiple scale. The length of the metal material delivered must be an integer multiple of the length specified by the buyer in the order contract (called a single size) (plus the saw edge). For example, the buyer requires in the order contract that the length of the single size is 2m, then the length is 4m when it is cut into double size, and 6m when it is cut into 3 times size, and one or two saw edges are added respectively.

The amount of saw blade is specified in the standard. Only positive deviations are allowed during delivery, and negative deviations are not allowed.

5. Short ruler

The length is less than the lower limit of the indefinite length specified in the standard, but not less than the shortest allowable length is called the short length. For example, the water and gas transmission steel pipe standards stipulate that 10% of each batch (calculated by the number of roots) 2-4m long short-foot steel pipes are allowed. 4m is the lower limit of the indefinite length, and the minimum allowable length is 2m.

6. Narrow ruler

The width is less than the lower limit of the indeterminate width specified in the standard, but not less than the narrowest allowed width is called the narrow size.

When delivering by the narrow gauge, attention must be paid to the narrow scale ratio and the narrowest scale specified in the relevant standards.