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Driers are widely used in steam systems; their function is to eliminate condensate water from the system while preventing steam leakage. In production, faults such as steam leakage from the trap and poor drainage of water are common. To improve the management of traps, we collaborated with Japan’s Fujihara Seisakusho (abbreviated as TLV) to inspect the traps in our plant’s ethylene facility, and repaired or replaced those that were faulty, achieving good results. I. Trap failures: Traps, also known as steam traps, can be classified into several types based on their working principle, including mechanical, thermodynamic, and thermostatic types. The common faults of steam traps include the following: (1) Blockage. Caused by poor drainage of the trap ； (2) Blowing and releasing. It is caused by steam being discharged along with the condensate, and is also known as internal leakage ； (3) Leakage. Steam and condensate are improperly discharged into the environment ； (4) Temperature control failure. It is caused by a discrepancy between the actual drainage temperature and the set temperature of the thermostatic drain valve. Troubles with steam traps not only affect the thermal efficiency of steam, but in severe cases, the presence of water in the steam pipes can lead to \"water hammer\" phenomena, posing a threat to safe operation. Since 1982, steam traps have been included in the **energy-saving product promotion program. With the improvement of various management measures and the establishment of relevant standards and regulations in recent years, the production and management of steam traps in China have seen significant improvements compared to before. However, due to technical reasons, there is still a certain gap between China and the world’s advanced level in terms of traps, with issues such as short lifespan and high failure rates existing to varying degrees. Furthermore, in the daily maintenance of traps, most enterprises in our country adopt a approach of simply installing them without further attention. Coupled with the lack of simple and accurate methods for detecting faults in these traps in a timely manner, this leads to a high rate of improper use of traps. According to a specialized sample survey, the rate of improper use of traps in our country exceeds 50%, while in Japan it is only 21.1%. Just due to this, our country incurs losses of several billion yuan each year. II. Detection Principle and Instrumentation TLV is a Japanese manufacturer specializing in steam traps; it developed the world’s first steam trap detector, whose memory stores the functional relationship between the steam leakage rate of various types of steam traps and the ultrasonic waves they emit. During testing, the detector can automatically determine the leakage and venting status of the steam trap based on the data from its ultrasonic receiver and temperature sensing values. In addition, the instrument stores the saturated temperatures of steam at various pressures, as well as the reference temperatures corresponding to different amounts of retained condensate water; therefore, the degree of blockage can be determined with relatively high accuracy using the temperature readings provided by the instrument. For the traps that have been identified as faulty and replaced, TLV conducts tests on its sophisticated \"Trap Fault Testing Bench\" to obtain accurate data, which is then used to further refine the data stored in the detector’s memory. Through years of practice and improvement, TLV’s method for detecting trap faults has become highly practical and accurate. The instrument we use is the JSTM3 ultrasonic detector provided by the Japanese company TLV (not for sale). It consists mainly of a wave sensing probe, a temperature sensing probe, and a display unit, and it allows for menu operations such as temperature selection as well as selection of the manufacturer or model. III. Fault Detection Process: The ethylene plant at Tianjin Petrochemical has a total of 417 various types of traps, of which 294 are domestic-made and were put into use in December 1998. A small number of the traps are foreign-made and were put into use in December 1995. Some of these traps are insulated, making it impossible to detect faults in them. In December 2002, we conducted actual inspections on 315 traps that met the conditions for testing. According to the statistics from December 2002, 125 of the inspected traps were in poor working condition, with an average failure rate of 40%; among them, those produced by Factory 920 had failure rates exceeding 40%. Preliminary calculations show that due to trap failures, the ethylene plant loses approximately 2,800 tons of steam per year. Based on the test results, we repaired or replaced the problematic traps. To evaluate the effectiveness of fault handling, the tested traps were retested in 2002, and the result showed that the failure rate of the traps was only 4.2%. Furthermore, by comparing the consumption in the ethylene plant, it was found that under the same conditions, more than 200 tons of steam are saved per month compared to before, indicating a very significant energy-saving effect.