一、前言在日用化工等行业中,经常碰到高碳有机化合物(如脂肪酸甲酯)的蒸馏操作,其塔顶的绝对压力往往要求达到0.5～0.7kPa(约4～5mmHg)。如用目前国产低绝对压力变送器,量程仍嫌太大,因此,不少厂家目前仍使用U型管水银(绝对)压力计。然而,由于水银柱高度甚小,不易读数,且读数误差也大,加之信号不宜远传、报警以及水银污染等问题,使用不尽满意。本文提出的一种温度式压力计的方案,有可能成为解决这一问题的简单可行的方法。二、结构及工作原理压力-温度转换器如图1所示。测量室1用密封件7密封,并与测压空间相通。室内装 I. Introduction In the chemical industry, daily chemical industry often encounters the distillation of high-carbon organic compounds (such as fatty acid methyl ester). The absolute pressure at the top of the tower often requires 0.5-0.7 kPa (about 4-5 mmHg). As with the current domestic low absolute pressure transmitter, the range is still too large, therefore, many manufacturers still use U-tube mercury (absolute) pressure gauge. However, due to the small height of the mercury column, not easy to read, and the reading error is also large, coupled with the signal should not be remote, alarm and mercury pollution problems are not satisfied with the use. This paper presents a temperature gauge program, may become a simple and feasible solution to this problem. Second, the structure and working principle Pressure - temperature converter shown in Figure 1. The measuring chamber 1 is sealed with a seal 7 and communicates with the pressure measurement space. Interior