Number of end cap heat treatment test plates?
Thread Content
One set of drawings covers the production of 20 units of equipment, made from S31603 material. The head steel plates ordered by the company come in 2 different batch numbers. As required by the client, solute treatment is necessary after the heads are formed; in this case, how should the test pieces from the base material of the heads be handled? One piece per furnace? Should there still be one per device?
By standard definition, it means one per device.
Although the standard is not explicit, based on the meaning of clause 9.2.2 in GB/T150.4-2011, it should be done according to the actual number of heat treatment furnaces; that is, there should be as many test plates as there are heat treatment furnaces. For greater safety, the steel plate lot number factor also needs to be considered. Example: If there are two furnace numbers in each of the two furnaces, then 4 test plates. That is, the number of test plates = the product of the factors that affect the mechanical properties of the head during the manufacturing process
This has little to do with the furnace batch number of the steel plate; what’s important is the batch for which solution heat treatment is carried out after head forming, with at least one test piece per batch.
This heat treatment is intended to restore the mechanical properties of the material, right? It must be related to the manufacturing process of the head; it probably has little to do with the furnace
What size are your end caps? How many end caps can be placed in one furnace during solution treatment? If the furnace is small and it’s necessary to process them one by one, then there’s no need to worry about anything; each end cap comes with it ； If several end caps are to be dissolved in the same furnace, then test plates should be included according to the furnace batch number of the steel plates; therefore, end caps made from steel plates of the same furnace batch number should be dissolved in the same furnace as much as possible. However, to perform solid solution treatment on a dozen or twenty end caps at once, it seems that ordinary pressure vessel manufacturers do not possess such heat treatment capabilities Some experts have also suggested that even for end caps manufactured from steel plates of the same batch, it is only possible to have one test piece per batch if water is introduced and removed simultaneously during cooling. If water is introduced one by one, then each end cap will still require its own test piece; after all, when water starts to flow into the first end cap, isn’t the second end cap still inside the furnace being kept at a constant temperature? . . . Anyway, encountering such problems is extremely frustrating.