U of ASME B31.1-2014 and B31.3-2014 in Alberta
PWHT requirements
ASME B31.1-2014 和 B31.3-2014使用（阿尔伯塔省）
PWHT要求
译者：孙明菊 QQ:274245152
2015/12/3
This Information Bulletin IB15-008 Rev. 1 superdes IB15-008 issued June 25, 2015.
此信息公告IB15-008版本1取代2015年6月25日发行的IB15-008
This information bulletin is issued to bring awareness of code changes and provide guidance to designers, owners and fabricators regarding the u of ASME B31.1-2014 Power Piping Code which was published on August 15, 2014 and ASME B31.3-2014 Process Piping Code which was published February 27, 2015.
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发出此信息公告为引起对于标准更改的关注，并为使用2014年8月15日发布的ASME B31.3-2014工艺管道和2015年2月27日发布的ASME B31.1-2014动力管道的设计方、业主和制造商提供指导。
ASME B31.1 Power Piping Code and ASME B31.3 Process Piping Code establish rules for preheat and post weld heat treatment (PWHT) and provide exemptions from PWHT bad on a material’s P Number, thickness, strength, and in some ca alloy content. The rules were not consistent in earlier editions (prior to 2014) of the two codes in terms of preheat requirements, preheat temperatures, the thickness that require PWHT, the definition of the thickness that require PWHT, the material properties that turn on the PWHT requirements, the holding temperatures, the holding times, the heating and cooling rates, and the terminology ud to describe the requirements.
ASME B31.1 和 ASME B31.3基于材料的P Number，厚度，强度，合金含量（某些情况下）制定了预热和焊后热处理的规则以及焊后热处理的免除。这些规则与这两个标准的早期版本（2014年以前版本）并不一致，在以下方面有不同：预热要求，预热温度，需进行焊后热处理的厚度要求，需进行焊后热处理的厚度定义，化学成分导致需焊后热处理，保温温度，保温时间，加热和冷却速率，和用
于描述要求的术语
To eliminate inconsistencies for preheat and PWHT, changes have been made to technical requirem
ents and format in the 2014 editions of the ASME B31.1 and ASME B31.3 Codes. To achieve consistent rules for materials by P Number (P1, P3, P4,
P5A, etc.), the piping codes have been revid in many places.中国梦的作文
为了消除预热和焊后热处理的不一致，2014年版的ASME B31.1和ASME B31.3中已经在技术要求和格式上作了修改。为了实现材料用P Number（P1，P3，P4，P5A等）分类后要求一致，这两个管道标准在许多地方进行了修正。 Revisions include:
修正包括：
Preheat temperature increa (e.g. P1 and P3 in both codes);
预热温度升高（例如，P1和P3，两个标准均如此）
PWHT holding temperature (e.g. P5A and P5B in ASME B31.1 and P3, P4, P5A, P5B, P6, P9A, and P10I in ASME B31.3);实用商务英语口语
焊后热处理保温温度（例如P5A以及P5B在ASME B31.1和P3，P4，P5A，P5B，P6 P9A和P10I在ASME B31.3）;
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PWHT holding time (incread for P9A, and P9B in ASME B31.3);
焊后热处理保温时间（P9A和P9B在ASME B31.3有所升高）;
The thickness that requires PWHT (revid for P1 in both codes);
需要焊后热处理的厚度（P1有修正，两个标准均如此）;
The governing thickness for exemption from PWHT (e.g. P3, P4, P5A) ;
焊后热处理免除的主要组件厚度（例如P3，P4，P5A）
The minimum holding time requirements have been reduced to 30 minutes for
P15E material group and to 15 minutes for all other material groups;
最小保温时间要求：P15E材料组已经降低到30分钟，所有其他材料组降低到15分钟; The hardness testing requirements have been deleted for all material groups;
所有材料组的硬度测试要求已被删除;
The PWHT requirements for P10 material group were deleted from Table 331.1.1 of ASME B31.3;
ASME B31.3表331.1.1删除对于P10材料组焊后热处理的要求;
Requirements for PWHT of P7 material group were added to Table 331.1.1 of ASME B31.3.
ASME B31.3表331.1.1加入P7材料组焊后热处理要求。
Persons responsible for piping design (owners and designers) should carefully review the piping codes and their specifications in light of the changes.
管道设计者（业主和设计人员）应仔细阅读这些管道标准的变化。
One change in particular has raid concerns. The piping codes now provide an exemption from PWHT of P1 materials (all groups) with no limitation on material thickness.
科普小故事一个特别的变化已引起关注。这两个管道标准目前提供所有P1材料（所有组）焊后热处理的免除，对于材料的厚度没有限制。
Concerns about this exemption include:
关于这项免除的问题包括：
快乐王子的故事 Pressure piping systems constructed of P1 material without PWHT may not
perform adequately, particularly when expod to certain process fluids.
沙湖公园 使用无焊后热处理的P1材料建造的压力管道系统可能无法充分满足使用要求，尤其是暴露在某些工艺流体中。
The stricter welding controls for preheat and multi-layer welding technique required during construction may not always be adequate or achievable, resulting in welded pressure piping systems that are more prone to rvice induced deterioration.
施工过程中所需的焊接过程中更严格控制预热和多层焊技术可能并不充分或可以实现的，从而导致焊接的压力管道系统更容易出现工况造成的恶化失效。
The Codes have become less prescriptive. This leads to the need for more engineering analysis and good judgment. The Codes are relying on knowledgeable urs (owners and designers) to specify PWHT (that is, to disallow the exemption) when they deem it necessary. Attention is directed to note 4 in Table 132.2 of ASME B31.1, or note 4 in Table 331.1.3 of ASME B31.3, which states ”(4) No exemptions are permitted for PWHTs required by the designer or the WPS”. Designers and owne
rs of pressure piping systems made of P1 materials that will be constructed to ASME B31.1-2014 or ASME B31.3-2014 should review their piping specifications and designs to ensure PWHT is performed when required for rvice conditions, fabrication conditions, or other circumstances specified by the owner or designer.
这两个管道标准已经变得不那么强制规定。这导致需要更多的工程分析和良好判断。标准靠知识渊博的使用者（业主和设计者）规定焊后热处理（即不允许免除），当使用者认为焊后热处理是必要的。注意力应关注于ASME B31.1表132.2备注4或ASME B31.3表331.1.3备注4，其中规定“（4）当设计者或WPS要求进行焊后热处理时，不得免除”。
