What are the differences in specific applications among disc-type, float-type, and bucket-type steam traps?

The purpose of steam traps is to drain water while preventing steam from passing through. Based on this purpose, steam traps are divided into three types: 1) Mechanical steam traps. Also known as float-type traps, these utilize the density difference between condensed water and steam; changes in the level of condensed water cause the float to rise or fall, which in turn opens or closes the valve element in order to prevent steam from passing through while allowing water to be drained. Mechanical steam traps have a low degree of subcooling; they are not affected by changes in operating pressure and temperature. Water is discharged as soon as it appears, preventing water from remaining in the heating equipment, which enables the heating equipment to achieve optimal heat exchange efficiency. With a maximum back pressure rate of over 80% and high operational quality, it is the ideal steam trap for heating equipment in manufacturing processes. Mechanical traps are generally installed on horizontal pipes. Mechanical traps include free ball type, free semi-ball type, lever ball type, inverted bucket type, etc. 2) Thermostatic traps: Thermostatic traps utilize the temperature difference between steam and condensed water to cause deformation or expansion of a temperature-sensitive element, which in turn drives the valve core to open and close the valve; they can be installed in any location. Thermostatic hydrostatic traps have a relatively large degree of subcooling, typically ranging from 15 to 40 degrees. They can make use of part of the sensible heat in the condensed water; high-temperature condensed water always remains before the valve, there is no steam leakage, and they offer significant energy-saving benefits. It is the ideal trap for steam pipes, heat tracing pipelines, small heating devices, heating systems, and small heating devices with low temperature requirements. Thermostatic traps include diaphragm type, bellows type, bimetallic strip type, etc. 3) Thermodynamic traps: Thermodynamic traps operate on the principle of phase change; by utilizing the differences in flow velocity and volume as steam and condensed water pass through, they create a pressure difference between the upper and lower parts of the valve element, which in turn drives the valve to open or close. Their installation location is not restricted. Since the operating power of thermodynamic steam traps comes from steam, there is significant steam waste. It has a simple structure, is resistant to water hammer, with a maximum back pressure ratio of 50%; it generates noise, the valve disc operates frequently, and its service life is short. Thermodynamic type traps include disc type, pulse type, orifice plate type, etc. 4) The following principles should be followed when installing steam traps: a. Impurities and slag in the pipes can easily enter the trap, causing blockages that may lead to leaks or damage to the trap. Therefore, the trap should be removed during the pipe purging phase and replaced with a short section; it can then be installed after the purging is complete. b. The installation location of the steam trap should be below the outlet of the equipment that uses steam; there should be a drop pipe of about 150 mm between the inlet of the steam trap and the outlet of the equipment. c. For heat exchange equipment equipped with temperature control, it is advisable to avoid raising the condensate discharge pipe upward, as a decrease in system load leads to a drop in pressure inside the heat exchanger, which is not sufficient to discharge the condensate; this can result in water accumulation and water hammer effects within the equipment. d. The steam trap should be as close as possible to the outlet of the equipment being drained to prevent steam lock-up. When the pipe between the condensate outlet and the steam trap is filled with steam, the condensate cannot reach the steam trap, resulting in a steam lock and water accumulation in the equipment, which affects operational efficiency. d. If a thermostatic steam trap is used in a steam space where water accumulation is not allowed, a cooling section must be installed upstream of the trap, typically about 2 meters long. e. If a bimetallic steam trap is installed in a system with backpressure, changes in backpressure will affect the discharge temperature of the condensate; an increase in backpressure leads to a decrease in the discharge temperature, which increases the risk of water accumulation within the equipment. f. When a mechanical steam trap is installed in an outdoor environment with low temperatures, insulation should be provided to prevent it from cracking due to freezing. g. Mechanical steam traps installed in outdoor areas with low temperatures require insulation to avoid cracking from freezing. If the back pressure is too high, a condensate transfer pump should be considered to handle the condensed water.

1. Once condensate is formed, it must be removed immediately; float-type, ES-type, and ER-type devices are suitable for this purpose. 2. For heat-traced pipe steam traps, disk-type and bimetallic temperature-controlled types are appropriate. 3. For urban steam heating equipment and pipelines that operate intermittently, inverted bucket-type traps are suitable