为防止换热器碳钢的腐蚀，也采取两项措施：一是将两台分子筛纯化器中心管的材质由原来的碳钢改成不锈钢；二是将碳钢材质结构的膨胀机后冷却器，更换成不锈钢结构，以确保空分装置安全、长周期运行。

In order to prevent the corrosion of carbon steel heat exchanger, but also to take two measures: one is the two sets of molecular sieve purification device central tube material changed by the original carbon steel stainless steel; the second is the carbon steel structure of the expander after cooler, replaced by a stainless steel structure, to ensure that the air separation device is safe and long period running.

　　为避免主换热器再发生堵塞故障，可采取以下措施：

The following measures can be taken to avoid the trouble of the main heat exchanger:

　　1）增加监测点。在空分装置改造时，卧螺离心机在主换热器的每个板式单元的各个通道的进出口管线上增设了温度测量点。

1) increase the monitoring points. When the air separation device is reformed, the temperature measuring point is added to the inlet and outlet pipeline of each plate unit of the main heat exchanger.

　　2）清洗主换热器。对主换热器进行清洗，同时增加辅助换热器单元。

2) cleaning the main heat exchanger（www.hreqi.com）. The main heat exchanger is cleaned, and the auxiliary heat exchanger unit is added.

3）加强现场的检修施工管理。要求对检修实行全过程控制。在装、卸分子筛之前，都必须在中心管上法兰处加装盲板。并采取专人负责、重点监督的方式，严格执行设备检修验收程序，严格把好检修质量关。进一步完善检修后的工艺处理步骤。对检修过程可能对设备造成的危害和隐患进行充分的评估，并制定相应的应急方案，最大限度地减少故障发生的可能性。　

3) to strengthen the maintenance of the site construction management. Requirements for the maintenance of the whole process of control. Before loading and unloading the molecular sieve, the blind plate must be installed on the flange of the central pipe. And take the person in charge, the focus of supervision, strict implementation of equipment inspection and acceptance procedures, strict quality inspection and maintenance. Further improve the process after the repair process. Full assessment of the hazards and hidden dangers caused by equipment in the process of maintenance, and make the corresponding contingency plans to maximize the possibility of reducing the occurrence of faults.