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Technical requirements for titanium used in containers

(1) The titanium used in containers is based on the current titanium material standards, so ordering should first meet the technical requirements in the titanium material standards
Due to the fact that these titanium material standards are not specific material standards for pressure vessels, but general material standards, the technical requirements in the titanium material standards alone cannot meet the technical requirements for titanium used in containers, and supplementary technical requirements must be proposed. Common supplementary technical requirements for titanium used in containers are proposed in this standard; The special supplementary technical requirements for titanium materials used in specific containers shall be proposed in the container design drawings and technical documents. The technical requirements for ordering titanium for containers shall be the sum of these three parts
(2) The deformed titanium used in containers is required to be supplied in an annealed state
In the current titanium product standards, only the tubes and heat exchange tubes are specified to be supplied in an annealed state, while the supply state in the standards for plates, bars, and forgings is chosen by the purchaser. If the purchase contract does not specify the requirement for supply in an annealed state, the supplier generally supplies in a hot or cold working state.
The standards for bars and forgings both stipulate that the mechanical properties are tested on the sample blank after heat treatment, indicating that the mechanical properties of the sample are qualified. This does not mean that the supplied titanium material is also in an annealed state, nor does it mean that the supplied titanium material has reached the qualified mechanical properties listed in the quality assurance certificate. The supplied titanium material should be required to be in the same annealed state as the mechanical performance specimen, that is, the specimen blank should be cut from the annealed titanium material or its extension.
(3) Titanium used in containers should ensure room temperature tensile strength σ B and specified residual elongation stress σ. R02 is a mandatory technical requirement.
In some titanium material standards σ. R02 does not have clear requirements, some are only additional requirements, and some are only tested when requested by the purchaser (only to provide measured data, not guaranteed). These cannot meet the requirements for titanium in containers, and should be clearly stated as mandatory requirements in the purchase contract. If the qualified indicators are not listed in the titanium material standard, the qualified indicators listed in Tables 4-1 to 4-5 of this standard can be followed, or the qualified indicators can be determined through negotiation. However, the maximum allowable tensile stress value at this time also needs to be determined separately.
(4) In the titanium product standards, only the standards for heat exchange tubes and forgings have listed non-destructive testing as a mandatory technical requirement. If the user has no special requirements, they can follow their non-destructive testing requirements. The titanium plate standard does not mention non-destructive testing requirements. CD1308-87 proposes five situations that require titanium plates to undergo ultrasonic testing.
1. Design temperature below -60 ° C
2. Design pressure exceeds 6
3. Used as an inner cylinder for multi-layer compression equipment;
4. Used as a lining for pressure vessels and heat exchangers of the Sana class;
5. Titanium plate thickness greater than 20mm
(5) Considering that the determination of non-destructive testing for steel plates in GB150 is mainly based on the thickness of the steel plate, thicker plates are prone to defects, and thick plates are generally used in situations with larger load-bearing capacity. Sometimes, when ordering, it is not possible to fully understand what application conditions each titanium plate is used for. Therefore, this standard only stipulates that titanium plates with a thickness exceeding 20mm should undergo ultrasonic testing. There is no unified regulation on which application conditions should undergo non-destructive testing. If necessary, it can be supplemented and proposed in the design drawings and technical documents
In addition, the GB/T5193 ultrasonic testing method standard is only applicable to workpieces with a thickness exceeding 13mm and is not suitable for testing thin plates. The Lamb wave ultrasonic testing method can be applied to titanium plates with a thickness of 0.5mm-13mm, but the Lamb wave ultrasonic testing method has not yet been listed as a formal standard, so there is currently no suitable testing method for thin titanium plates used for lining It is not advisable to conduct testing according to general regulations. Non destructive testing requirements are not listed in the general titanium tube standards. This standard stipulates that when the design pressure exceeds 10MPa, ultrasonic or eddy current testing should be carried out. Ultrasonic non-destructive testing is only considered as an additional technical requirement in the titanium rod standards, and this standard does not make unified provisions. It is determined by the design according to specific circumstances
(6) The standards for titanium pipes and titanium heat pipes both specify that the manufacturing methods for pipes are divided into three types: rolling (drawing), welding, and welding rolling. When placing an order, the contract should indicate which type it is, because the inspection technical requirements and application performance (such as allowable stress) of these pipes are different.
These five situations. The first four are the application conditions for titanium materials. Only the latter parameter belongs to the titanium plate itself.

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