热电偶简介：                                                                                                                           在工业生产过程中，温度是需要测量和控制的重要参数之一。在温度测量中，热电偶的应用极为广泛，它具有结构简单、制造方便、测量范围广、精度高、惯性小和输出信号便于远传等许多优点。另外，由于热电偶是一种有源传感器，测量时不需外加电源，使用十分方便，所以常被用作测量炉子、管道内的气体或液体的温度及固体的表面温度                                                                              热电偶分类：                                                                                                                            1.按固定装置型式分类热电偶作为主要测温手段，用途十分广泛，因而对固定装置和技术性能有多种要求，因此热电偶的固定装置分为六种：无固定装置式、螺纹式、固定法兰式、活动法兰式、活动法兰角尺形式、锥形保护管式六种。                                                                                                2、按装配及结构方式分类根据热电偶的性能结构方式可分为：可拆卸式热电偶、隔爆式热电偶、铠装热电偶和压弹簧固定式热电偶等特殊用途的热电偶。                                                                    热电偶优点:                                                                                                                            1、测量精度高。因热电偶直接与被测对象接触，不受中间介质的影响。                                       2、测量范围广。常用的热电偶从零下50度-1600度均可连续测量，某些特殊热电偶zui低可测到-269度（如金铁镍铬），zui高可达2800度（如钨-铼）。                                                                        3、构造简单，使用方便。热电偶通常是由两种不同的金属丝组成，而且不受大小和开头的限制，外有保护套管，用起来非常方便。                                                                                                      热电偶主要特征：                                                                                                                     1、装配简单，更换方便；                                                                                                            2、压簧式感温元件，抗震性能好；                                                                                             3、测量精度高；                                                                                                                       4、测量范围大（－200℃～1300℃，特殊情况下－270℃～2800℃）；                                        5、热响应时间快；                                                                                                                    6、机械强度高，耐压性能好；                                                                                                  7、耐高温可达2800度；                                                                                                             8、使用寿命长。