In the early days, multi-standard pipes were advocated or required by the project party, so that the project party could purchase and use them in a unified manner, saving time and trouble.
At the beginning, multi-standard pipes mainly existed in parallel with American standards and American standards, and the main use direction was export, mainly consisting of "three-standard pipes" and "five-standard pipes". Later, because many designs of domestic petrochemical projects were implemented in accordance with American standards, multi-standard pipes were gradually introduced into the procurement and use of domestic petrochemical and chemical projects.
As time goes by and the market develops in a refined way, the classification of multi-standard pipes on the market is now more professional and diversified.

At present, in addition to "three-standard pipes" and "five-standard pipes", there are also "double-standard pipes" and "four-standard pipes" on the market. Moreover, they are not limited to the coexistence of American standards and American standards, but also between national standards and national standards, and between national standards and American standards.

The multi-standard pipes on the market are no longer dominated by the project users, but have become initiated by the suppliers (factories, market traders).
The reason why multi-standard pipes exist:
First of all, fundamentally speaking, it is achievable. The so-called multi-standard pipes, as the name suggests: the same steel pipe meets more than two execution standards and materials. It can meet both here and there, and the chemical elements, mechanical properties, and process technology requirements of several standards can be met at the same time.
In the early stage: multi-standard pipes are mainly advocated by the project party for the convenience of centralized procurement, saving time, effort and trouble;
As the market gradually changes from a seller's market to a buyer's market, the advantages of "saving time, effort and trouble" are transferred to the market suppliers, with more significant economic benefits. For example: if the same amount of funds is used to produce/stock one standard material, now it can produce/stock two, three, four... The stocking products are more complete, and can provide timely services for the targeted, specific and diversified needs of buyers.