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Types of steam traps recommended for use in various steam heating equipment: For steam main pipes, heat tracing pipes, and steam jacket systems, disk-type and float-type steam traps are recommended. For steam-water separators, float-type traps are used. In heating units and hot air blowers, float-type traps are appropriate. For heating radiators, bellows-type, bimetallic, and diaphragm-type traps are suitable. On the steam inlet side of heat exchangers, float-type traps are used when a temperature control valve is installed; bimetallic and float-type traps are used when no such valve is present. For evaporators, float-type and downward-opening float-type traps are used. For jacketed pots, bimetallic traps are suitable. For heating coils submerged in liquid tanks, float-type traps with anti-steam-lock devices are used when a temperature control valve is installed; bimetallic and diaphragm-type traps are used when no such valve is present. For drum dryers, float-type traps (with anti-steam-lock devices) and bimetallic traps are used. For dry cleaners, disk-type, bimetallic, and diaphragm-type traps are suitable. For drying chambers, float-type traps are used. For disinfectors, bellows-type and bimetallic traps are appropriate. For sulfiding machines, float-type and downward-opening float-type traps are used. For laminating presses, disk-type and bimetallic traps are used. For steam heating equipment operating under pressures below atmospheric pressure, pump-type steam traps are recommended. Calculation of the steam drainage volume in steam pipes: The estimated initial condition for calculating the steam drainage volume in steam pipes is that the temperature rise rate of the heated pipes should be 2°C–3°C per minute, with a maximum of 5°C per minute; therefore, 5°C per minute is used in the calculations. The temperature rise rate of the insulation material is taken as half of the temperature rise rate of the steel pipe. 3.1.2 Formula for calculating the starting drainage volume The starting drainage volume M = 60×n×(G1×C1×Δt1 + G2×C2×Δt2)/(Ig–Ib), where G1 is the weight per unit length of the steel pipe or the weight of a single valve ； G2 — Weight of insulation material per unit length of steel pipe ； C1 —— specific heat of steel pipe, calories/kg℃ ； C1——Specific heat of insulation material ； Δt1——Temperature rise rate of the steel pipe, °C/min ； Δt2 —— Temperature rise rate of the insulation material, °C/min (it can be calculated by taking Δt2 as 0.5Δt1, which is 2.5°C/min) ； Ig——steam enthalpy, kcal/kg ； Ib —— Enthalpy of saturated water at the initial pressure in the steam pipeline, kcal/kg ； n——pipe length ； Calculation of the amount of water to be drained during operation of steam pipes. Calculation of the water drainage volume in superheated steam pipes: The usual value for water drainage is given by the formula G=q×n/(Ig-Ib), in kilograms per hour ； q=Heat loss from pipes and valves ； It can be based on the data in the specified range for the unit heat loss of pipes per the regulations ； Ig = enthalpy of superheated steam at rated parameters, kcal/kg ； Ib=enthalpy of saturated water at rated parameters ； n=pipe length or number of valves ； In wet steam pipelines, the calculation of the amount of drain water often requires taking into account the moisture present in the wet steam itself. Therefore, compared to superheated steam, in addition to the drain water resulting from heat loss in the pipeline, the amount of drain water caused by the moisture contained within the wet steam must also be considered. At present, in China’s CP1000 nuclear power units, the extraction steam from stages 5, 6, and 7 located before the main steam pipe and the steam-water separation reheater is all wet steam; therefore, the calculation of the amount of water drained from the wet steam pipes is an important issue in the thermal system of nuclear power units. Considering the safety and reliability of engineering applications, a water drainage capacity of 0.1 in terms of humidity is uniformly adopted. Therefore, the formula for the regular drain volume of wet steam pipes is as follows: Regular drain volume G = q×n/(Ig-Ib) + W×x×0.1, in kilograms per hour. Requirements for installing steam traps: 1. Before installing the steam trap, it is necessary to purge the pipe with steam under pressure in order to remove any debris from within the pipe. 2. A filter should be installed in front of the steam trap to ensure that it is not clogged by debris in the pipes, and the filter should be cleaned regularly. 3. Valves should be installed before and after the steam trap to facilitate its timely maintenance. 4. The direction of the condensate flow must be in line with the arrow indicator on the steam trap. 5. The drain valve should be installed at the lowest point of the equipment outlet to discharge condensate in a timely manner and prevent vapor lock in the pipes. 6. If there is no space at the lowest point of the equipment to install a steam trap, a check valve (condensate lift joint) should be installed at the lowest outlet point to raise the condensate level before installing the steam trap, thereby preventing vapor lock. 7. The outlet pipe of the steam trap should not be submerged in water. (If submerged in water, a hole should be drilled at the bend to break the vacuum and prevent sand from being sucked back in.) ) 8. Mechanical steam traps should be installed horizontally. 9. Steam traps should not be installed in series. 10. Each piece of equipment should be equipped with its own drain valve. 11. A supercooled pipe without insulation of more than one meter is required in front of thermostatic steam traps; other types of steam traps should be placed as close as possible to the equipment. 12. When selecting a steam trap for drum-type drying equipment (with siphon tube), please specify that a steam trap equipped with an anti-airlock device should be used to prevent air locking in the equipment. 13. If condensate is to be recovered after the steam trap, the outlet pipe of the steam trap should be connected to the main pipe above the recovery main pipe, in order to reduce backpressure and prevent backflow. 14. If condensate is to be recovered after the steam trap, pipelines of different pressure levels should be separated for recovery. 15. The main condensate recovery pipe downstream of the steam trap must not have a slope, as this will increase the back pressure on the steam trap. 16. A steam trap should be installed before the condensed water enters the main recovery pipe, behind the steam trap, to prevent backflow of the condensed water. 17. Install steam traps on the steam pipes; a condensate collection tank should be provided on the main pipe, with its size being close to the radius of the main pipe, and small pipes should then be used to lead the condensate to the steam traps. 18. When a mechanical drain valve is not in use for an extended period of time, the drain screw should be removed to release the water inside, thereby preventing freezing. 19. If it is detected that the steam trap is leaking steam, it is necessary to drain waste water and clean the filter screen promptly. Regular inspections should be carried out based on actual usage conditions, and any faults should be repaired immediately. It should be inspected at least once a year to remove any impurities inside.