ASME压力容器焊后热处理程序

ASME压力容器焊后热处理程序

Postweld Heat Treatment Procedure

1. General总则

This procedure is supplemented to the “Heat Treatment Instruction ”(specific heat treatment instruct ion), and is applicable to the boilers and pressure vessels and parts of carbon steels (PNo1 Gr.Nos 1, 2&3) fabricated according to the latest ASME Code Sect Ⅰ,B31.1and VIII Div.1.

本程序是对”热处理工艺卡”(专用热处理工艺)的补充,用于按ASME规范第Ⅰ卷,B31.1和第Ⅷ卷第１分册的要求,碳钢(PNO组1、2或3)所制造的锅炉/压力容器和部件; For the other materials, the applicable procedure and condition will be added or provided. 对于其它材料,将增加或提出相应程序或条件;

2. Personnel人员

The PWHT operator shall be familiar with the general requirements of heat treatment and has been properly trained.

焊后热处理操作者应熟悉热处理的一般要求并经过适当的培训;

3.Equipment设备

According to the specific situation根据具体情况编制

4. Procedures工艺

One of the following procedures may be used for the PWHT:

焊后热处理应按下列工艺之一执行;

4.1 If it is practicable, the vessel shall be heated as a whole in an enclosed furnace. 如可行,整台容器装入封闭炉内加热;

4.2Heating the vessel in more than one heat in furnace, provided the overlap of the heated sections of the vessels at least 5 ft. When this procedure is used, the portion outside of the furnace shall be sh ielded so that the temperature gradient is not harmful.

容器在一加热炉内分几段加热,要求被重复加热的各段至少有5英尺长(1.5m),当采用这种工艺时, 在炉外的部分应予以覆盖保温,以免产生有害的温度梯度;

4.3.Heat of the shell sections and/or portions of the vessels to postweld heat treat longitudinal joints or complicated welded details before joining to make the completed vessels. When the vessel is req uired to be PWHT, and it is not practicable to PWHT the completed vessel as a whole or in two or more heats as provided in 4.2 above, any circumferential joints not previously PWHT may be therea fter locally PWHT by heating such joins by any appropriate means that will assure required uniform ity. As a minimum, the soak band shall contain the weld, heat affected zone, and a portion of base m etal adjacent to the weld being heat treated. The minimum width of this volume is the widest width of weld plus T or 2in(51mm), whichever is less, on each side or end of the weld. The portion outsid e the heating device shall be protected so that the temperature gradient is not harmful. This procedur e may also be used to PWHT portions of new vessels after repairs.

在组装成整体容器之前,可对筒节或容器的的纵焊缝或结构复杂的焊接点进行焊后热处理.对要求焊后热处理,但有不能整体热处理,或如 4.2条所述分两次或多次热处理,其上任何未经焊后热处理的环焊缝,可采用任何能达到保证均匀要求的加热方法进行局部热处理.此时加热应包括焊缝热影响区及临近的母材,其宽度应为焊缝最大宽度处的每侧各加T或2英寸(51mm)两者之中最小者. 加热装置以外的部分应予以覆盖保温,以免产生有害的温度梯度.该工艺还可用于新容器返修后各部分的焊后热处理;