Steel Pipe knowledge

Steel Pipe knowledge terms sum up to double-click automatically scroll Publisher: Hao Xin Tong Steel Pipe released 2010 -4-19 Read: 46 【Font: Big Middle Small】| a generic term ① Delivery status refers to the final plastic deformation of the delivery of products or the final heat treatment condition. like without heat treatment delivery, said hot-rolled or cold drawn (rolled) or manufactured state; said heat treatment after heat treatment delivery status, or according to the type of heat treatment that normalized (normalization), tone quality, solution annealed condition when ordering, delivery status be specified in the contract (2) the actual weight of the actual weight of the delivery or delivery by theoretical weight - the time of delivery, the product weight by weighing (weighing ) Weight delivery; delivery of the theoretical weight - the weight of their products is said that the size calculated from the weight

of steel public the following formula (which requires the theoretical weight of Delivery, to be specified in the contract): Steel pipe the theoretical weight of m (the density of steel for 7.85kg/dm3) formula: where W = 0.02466 (DS) S: W - steel per meter Theoretical Weight, kg / m; - steel pipe of nominal outer diameter, mm ; the S - the public of the steel pipe wall thickness, mm ③ ensure that the conditions existing provisions of the standard projects to test and ensure that the provisions of the standard, called the warranty conditions. ensure that the terms and conditions are divided into: A, the basic guarantee conditions (also known as will security conditions) regardless of wh|
actual operation to cut out absolutely definite length is unlikely, so theether the customer specified in the contract shall be subject to the standard requirements for the inspection and to ensure that the test results meet the standard requirements such as chemical composition, mechanical properties, dimensional deviation and surface quality as well as crack detection, hydrostatic test or flattening or flaring process performance experiments are a necessary condition B, the agreement of the guarantee conditions: standard In addition to the basic guarantee for the condition, there are "based on the demand side requirements, supply and demand both parties, and in the contract note? quot ; or "demand-side requirements ... should be specified in the contract"; there are customers, the basic guarantee of the standard conditions of tightened requirements (such as composition, mechanical properties, size deviation, etc.) or increase the test items ( such as steel pipe ovality, uneven wall thickness, etc.) The above terms and requirements, in order, by supply and demand, both parties signed supplier agreement and indicate in the contract. Therefore, these conditions are also known as the agreement to ensure that conditions of an agreement guarantee conditions of the product, like all the fare increase. ④ The approved standard "lot"

refers to a test unit, namely the inspection lot. approved terms of the delivery unit group, said the consignment. when the delivery volume a delivery batch includes several inspection lot; when volume is low, a test batch can be divided into several consignments. "approved" the composition is usually the following provisions (see the relevant standard): A delivery of each batch should by the same grade (steel grade), the same stove (pot) or parent furnace, specifications and heat treatment (furnace) steel pipe B, high-quality carbon steel tubes, fluid tubes, can be different furnace (tank) with grades, specifications and heat treatment (furnace) steel pipe, welded steel pipes each batch should be the same grade (steel grade) of the same specifications of the steel pipe. ⑤ high quality steel and high quality steel the GB/T699-1999 GB/T3077-1999 standard, the grade is followed by the letter "A", High quality steel, contrary to the general high quality steel. high quality steel in the following part or all is better than high quality steel: A, narrow composition content range; B, and to reduce the harmful elements (such as sulfur, phosphorus, copper) content; C, to ensure higher purity (requires non-metallic inclusion content is less); D, to ensure high mechanical properties and process performance. of ⑥ vertical and horizontal standards, said longitudinal parallel with the machining direction (ie, along the processing direction) who refers to; transverse means perpendicular to the machining direction (machining direction of the steel tube axial). do impact
|| energy experiment, the longitudinal specimens fracture due perpendicular to the machining direction. it said transverse fracture; transverse specimens of fracture due to the machining direction parallel, therefore, said longitudinal fracture two. steel pipe shape, and size terminology ① public said the size and actual size A,, nominal size: is the name of the standards set forth in size,

users and producers want to get their ideal size, order size is also specified in the contract, actual size: the actual size of the production process, the size is often greater than or less than the nominal size such greater than or less than the nominal size of the phenomenon is called the deviation. ② deviations and tolerances A deviation: in the production process, due to the actual size is difficult to reach the public said the size requirements, that is often greater than or less than the nominal size, the standard set forth in The actual size and nominal allowed there is the difference between the size difference is positive is called a positive deviation, the difference is called negative deviation of the negative B tolerance: standard specified in the absolute value of the positive and negative deviation

and called tolerance, also called the "tolerance zone". deviation is directional, ie, "positive" or "negative"; tolerance is non-directional, so the deviation of called "tolerance" or "negative tolerance" it is called. ③ delivery length delivery length, also known as the required length or contract length. standard delivery length of the following provisions: the usual length (also known as non-definite length): Where the length of standard requirements within the length and fixed length requirements are referred to as the usual length. such as structural tube standard requirements: hot rolled (extrusion, expansion) steel tubes 3000mm ~ 12000mm; cold drawn (rolled) steel pipe 2000mmm ~ 10500mm B Length Length: Length length in the range of the usual length is required in the contract of a fixed-length size, but the| standard length length requirements positive deviation of the allowable value.