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Seamless Steel Tubes For Standard Commonly Used The Term

Oct 26, 2016

① seamless steel tube delivery status

Refers to the delivery of the final product plastic deformation or the State of the final heat treatment. Generally do not undergo heat treatment delivery of hot rolled or cold rolled (rolling) or manufacturing States; after heat treatment heat treatment State of delivery, or according to the type of heat treatment are fire (Chang Hua), quenching and tempering, solution annealed State.  When you place an order order status should be indicated in the contract. II according to the actual weight of shipment or according to the theoretical weight delivery

When the actual weight of the delivery, the product weight is by weighing (weigh in) weight of the delivery;

Theoretical weight of delivery, the product weight is calculated from the nominal size of steel weights. The formula is as follows (requirement according to the theoretical weight delivery, should be stated in the contract):

Seamless steel pipe weight per meter (steel density is 7.85kg/dm3) formula:


Type: seamless w/m weight, kg/m;

D nominal outside diameter of the seamless steel tube, mm;

S nominal wall thickness of seamless steel pipe, mm.

③ the guarantee conditions

Test project as required by current standards and ensure compliance with standards requirements, referred to as the guarantee conditions. Guarantee conditions can be divided into:

A basic guarantee conditions (also known as the conditions). Regardless of whether the customer indicated in the contract. Must be carried out according to the standard of the examination, and to ensure that test results are consistent with standards.

Such as chemical composition, mechanical properties, dimensions, surface quality and testing, such as pressure or collapsing or expanding process experiments are required conditions.

B, the agreement guarantees: standard in addition to the basic guarantee conditions there "according to requirements, after consulting both supply and demand, and in the contract note? quot; or" when demand-side requirements ... ... , Should be indicated in the contract "; and some customers, tightening demands on the basic guarantee in standard conditions (such as composition, mechanical properties and dimensional deviations, etc) or additional inspection item (such as wall thickness of seamless steel pipe ovality, inequality). The terms and requirements, in order, by both parties, signed a technical agreement and indicated in the contract. Therefore, these conditions are also referred to as protocol conditions. Guarantee conditions of the agreement, are asking for toll increases.

④Standard in the "batch" means an inspection unit, namely, inspection lot. If the delivery unit unit, called consignment. When delivery volume is large, a consignment may consist of several inspection lots; when delivery volume small, a test delivery can be divided into several instalments.

"Batch" components typically have the following requirements (see standards):

A, each batch shall consist of the same grade (grade), the same stove (canned), or the same number, same size and the same heat treatment system (furnace) composed of seamless steel tubes.

B, for high quality carbon steel seamless tubes seamless structure, fluid, can be different furnace (tanks) of the same brand, same size and the same heat treatment system (furnace) composed of seamless steel tubes.

Each batch should be from the same grade of c, welded steel (steel), composed of steel of the same specifications.