Q345钢的CO2气体保护焊的工艺研究

Q345钢的CO2气体保护焊的工艺研究

摘要

本文以Q345钢的CO2气体保护焊的工艺为例对其进行了分析与研究。

Q345钢综合力学性能良好，低温性能亦可，塑性和焊接性良好，用做中低压力容器、油罐、车辆、起重机、矿山机械、电站、桥梁等承受动载荷的结构。热轧或正火状态使用，可用于-40℃以下寒冷地区的各种结构。

二氧化碳气体保护焊目前已发展成为一种重要的熔焊方法，具有成本低、效率高、操作灵活等特点。广泛应用于汽车、工程机械、造船业、机车、电梯、锅炉压力容器等制造业，以及各种金属结构和金属加工机械的生产。

本文首先分析了Q345钢的焊接性，其次对CO2气体保护焊特点和工艺的进行了分析，从而确定了Q345钢的CO2气体保护焊焊接工艺。通过工艺参数的优化选择，不仅能减少焊接过程中的常见问题，而且有效减少焊接缺陷的出现，并能提高生产效率，节约生产成本。

关键词：Q345钢，CO2气体保护焊，工艺，焊接缺陷

TECHNOLOGY OF STUDY Q345 STEEL BY CO2 GAS

WELDING PROTECTION

ABSTRACT

In this paper, Q345 Steel CO2 gas shielded welding process as an example of its analysis and research.

Good mechanical properties of Q345 steel, low temperature performance can, plastic and welding of good, used in low pressure vessels, tanks, vehicles, cranes, mining machinery, power plants, bridges and other structures to withstand dynamic load, mechanical parts, building structures, General metal structure, use of hot-rolled or normalized condition, the following can be used in -40 ℃cold regions of the various structures. In order to improve efficiency, cost savings, and more use of welding technology.

Carbon dioxide gas welding protection has grown to become an important by welding, with low cost, efficient and flexible operating characteristics. It is widely used in the car engine, shipbuilding, construction machinery.The boiler pressure vessel, such as manufacturing, and all sorts of metal and metal processing machinery production.

This paper analyzes the Q345 steel welding, followed by CO2 gas shielded welding on the characteristics and processes are analyzed to determine the Q345 steel CO2 gas shielded welding process. Optimization of processing parameters, not only can reduce the welding process of frequently asked questions, and effectively reduce the appearance of weld defects, and can improve production efficiency, saving production cost.

KEY WORDS: Q345 steel，CO2 gas shielded welding，technology，defects of welding

目录

摘要 (Ⅰ)

ABSTRACT (Ⅱ)

目录 (Ⅲ)

前言 (1)

第1章Q345钢及CO2气体保护焊简介 (3)

1.1 Q345钢简介 (3)

1.1.1 Q345钢的应用与分类 (3)

1.1.2 Q345化学成分及力学性能分析 (3)

1.1.3 Q345钢的焊接特点 (4)

1.2 CO2气体保护焊简介 (4)

1.2.1 CO2气体保护焊发展史 (5)

1.2.2 CO2气体保护焊特点 (6)

1.2.3 CO2气体保护焊冶金原理 (6)

1.2.4 CO2气体保护焊的熔滴过渡形式 (7)

第2章CO2气体保护焊工艺 (8)

2.1 焊前准备 (8)

2.1.1 坡口设计 (8)

2.1.2 坡口加工方法与原理 (9)

2.1.3 定位焊缝 (9)

2.2 焊接参数的选择 (9)

2.2.1 焊丝直径的选择 (10)

2.2.2 焊接电流的选择 (10)

2.2.3 电弧电压的选择 (11)

2.2.4 焊接速度的选择 (11)

2.2.5 焊丝伸出长度的选择 (11)

2.2.6 电流极性的选择 (12)

2.2.7 气体流量的选择 (12)