A cold wave is coming! Sharp drop in temperature! How should factories prevent condensation and freezing?

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A cold wave is approaching, bringing a sharp drop in temperature; as the weather gets colder, how should factories prevent condensation and freezing? What should be done after a freeze occurs? Let’s take a look together! Winter anti-freezing and handling of factory pipelines 1. Water lines for process use. For any installations on the ground that use a small amount of water, it is necessary to ensure that there is a drain valve at the end of the pipeline to maintain a continuous flow of water and prevent freezing; where possible, insulation should be added to the pipeline. 2. For water lines that are used intermittently, electric heating tapes must be installed for insulation; otherwise, they cannot be used. 3. For water lines that are not in use during winter, the flanges on both ends should be removed to drain all the water stored within them. If possible, industrial air should be used for purging to ensure that the pipes do not get filled with water again. If the valves do not seal properly, blind flanges should be installed at the flanges on both ends, and these should be registered and labeled accordingly. 4. For some pipelines that are not used in normal production, being in a dormant state for long periods can result in water accumulating in dead corners and freezing; once these pipelines need to be used, this can cause blockages and disrupt production. For such pipelines, before winter arrives, it is necessary to clean and flush them with an appropriate flow rate, then close the relevant valves to keep them in a standby state. 5. For the fire hydrants in the fire water supply system, as well as the valve chambers for these systems, it is necessary to close the valves located in those chambers and drain the water from the hydrants, so that they are ready for use at any time. A double-layer manhole cover should be used in the fire well (one of which is a thermal-insulating cover). Freezing occurs; once the equipment freezes, it should be thawed using steam or hot water. The thawing of cast iron pipes and equipment must be done slowly to prevent cracking. It is forbidden to heat frozen pipes or equipment while they are still sealed – they must first be opened to allow air to escape. Horizontal pipes should be thawed from bottom to top, while vertical pipes should be thawed from top to bottom. Any cracks that appear must be reported. 30 Tips for Preventing Freezing in Factories 1. Take proper personal protective measures, dress warmly, and ensure slip prevention when going up and down the towers during inspections. 2. Strengthen dehydration efforts by promptly removing water from various dehydration points to prevent freezing and blockages. 3. Pay attention to the level gauges in use; if the angle valves at the top and bottom of these gauges freeze up, it will affect the accuracy of the measured level. If the transmitter associated with the level gauge freezes up, it will impact mechanical movement and current flow, thereby affecting the accurate measurement of the level. 4. The temperature of the circulating water should not be allowed to drop too low; it must remain above 8 degrees. If it falls below 8 degrees, freezing in the auxiliary lines of the cooler can occur, and in severe cases, the pipes may even crack. 5. Insulate the pipes in the stagnant water areas of the workshop’s circulating water system ； For decommissioned circulating water pumps, backflow prevention measures shall be taken, and all water must be drained. 6. For equipment that is not in use in the workshop, such as make-up water pumps, circulation water pumps, coolers, condensers, etc., measures such as draining water and conducting regular inspections should be taken. Compressor cooling water is regularly checked by operators to ensure that the water valve remains open at all times. 7. If a liquid hydrocarbon pipeline freezes and gets blocked, be careful of physical explosions when using steam to clear the pipeline; do not force the cleaning process, rather preheat it gradually. 8. The on-site pressure gauge may also give false readings when frozen/clogged; judgment should be made based on experience. Any uncertainties must be reported promptly for handling. 9. When purging frozen and blocked pipelines, use steam to purge the elbows. 10. Pay attention to enhanced liquid removal from gas pipelines to prevent liquids from entering the boiler. Check the natural gas lines to prevent blockages caused by frozen crystal structures. 11. Strengthen inspections to monitor the temperature at various locations. 12. The water supply pipeline should be kept from being completely closed to maintain a continuous flow of water. 13. For decommissioned equipment, blind flanges should be installed at the connections to the production system, any accumulated water must be drained, and the area should be purged thoroughly. For equipment left outdoors and those without covers, take measures to prevent water, snow, and ice from accumulating and damaging the equipment. For outdoor equipment, the frequency of patrol inspections and cranking must be increased. 14. For equipment used in production and daily operations, as well as those that are temporarily out of use, steam pipelines, and control valves must be equipped with anti-freezing insulation measures. Any accumulated water should be drained, or a system that maintains a small continuous flow of water and steam should be employed to achieve both anti-freezing effects and water conservation. After the supply of water and steam is stopped, the systems must be thoroughly purged. 15. Strengthen routine inspections for dehydration; check for dehydration at the lowest points of various equipment and pipelines. The cooling water supply to pumps must not be interrupted, and heating systems must remain functional. Pressure gauges and level gauges should be checked regularly. Steam and water hose connections as well as other related components must ensure continuous steam output and steady flow of water. 16. Valves whose switches do not move should not be forced to be switched; vehicles whose control panels do not function should not be operated. 17. Frozen cast-iron valves should be slowly heated using warm water or a small amount of steam to prevent damage from sudden heating. 18. Construction and domestic water should be directed into gutters or areas that do not interfere with traffic, and ice slush must be removed at all times. 19. Strengthen management by establishing records for anti-freezing and anti-condensation measures (including accident logging, the condition of anti-freezing and anti-condensation equipment, and pipelines prone to freezing). 20. Valve chambers, fire hydrants, and pipe trenches in low-temperature areas should be inspected one by one to drain any accumulated water, and anti-freezing and insulation measures should be taken. 21. Heating with high-pressure steam is strictly prohibited; care must be taken to prevent high-pressure steam from entering the low-pressure system. The high-pressure and low-pressure steam return pipes must not be connected to each other. A pressure reducing valve should be installed on the piping of steam-heated radiators; the pressure gauge connected to this valve must be calibrated properly. The radiators must be tested for leaks by introducing steam before they can be used. 22. Whenever working at heights, it is necessary to ensure that all water accumulation, snow, and ice in the work area have been removed before proceeding. 23. Therefore, for steam pipelines (except fire protection steam), close the root valve and the wall valve, open all drain valves to drain any remaining water, and purge them with nitrogen. 24. All drain points must be drained every hour. 25. After shutting down the circulating water system, the low-point drain must be opened to remove all water, and the area should be blown clean with air. 26. The drainage pipelines of the adsorption tower, desulfurization tower, water washing tower, and gas-liquid separator outside the workshop are protected against freezing using electric heat tracing. To prevent freezing, ensure that water separators and coolers in the workshop are drained completely after shutdown. 27. When indoor heating is turned off, safety facilities such as tap water, eye wash stations, and fire extinguishers in the workshop are kept from freezing using electric anti-freezing systems. 28. After water is sprayed on the workshop floors and platforms, they must be cleaned immediately to prevent icing. Workshop staff should enhance their safety awareness and precautionary mindset when going on platforms and climbing stairs. Regulations on Anti-condensation and Anti-freezing Measures of a Certain Company 1. Purpose and Scope: These regulations are formulated to prevent damage to equipment, pipelines, and other auxiliary facilities caused by freezing and condensation during low-temperature periods, and to ensure that appropriate anti-freezing and anti-condensation measures are taken. These regulations apply to all units under the company. 2. Management Responsibilities 2.1 The Production Department is the designated department in charge of anti-freezing and anti-condensation measures; it is responsible for organizing and coordinating inspections and evaluations of these measures across various units, as well as overseeing the implementation of such measures by those units. 2.2 The Equipment Management Department is responsible for the insulation management of equipment, pipelines, etc., and is in charge of organizing the repair and replacement of equipment that has been damaged due to freezing. 2.3 Each workshop is responsible for formulating its own anti-freezing and anti-condensation plans, as well as for carrying out regular inspections of these measures and ensuring their proper implementation. 3. Management Requirements
3.1 Preparations for preventing condensation and freezing
3.1.1 The period from November 1 each year to March 15 of the following year is designated as the period for preventing freezing and condensation. 3.1.2 Each workshop shall complete the preparation (or revision) of its anti-freezing and anti-condensation plan by September 30 of each year, and submit it to the Production Department for approval. The Production Department shall complete the review of the anti-condensation and anti-freezing plan and issue it by October 15. The anti-freezing and anti-condensation plan should be accompanied by an \"Anti-Condensation and Anti-Freezing Inspection Sheet\" to serve as a basis for implementation at the work site. 3.1.3 Each workshop shall formulate a procurement plan for anti-freezing and anti-condensation materials based on the anti-freezing and anti-condensation plan as well as actual needs. The Supply and Sales Department makes purchases in accordance with the approved plan to ensure the supply of anti-freeze and anti-congealing materials. 3.2 Standards for anti-condensation and anti-freezing measures 3.2.1 Anti-condensation and anti-freezing for in-use pump equipment When the ambient temperature is near 0°C or below, the frequency of inspections of the pump cooling water system should be increased to prevent interruptions in the cooling water supply or blockages in the pipelines that could lead to a lack of water flow. During low-temperature and cold wave periods, when the cooling water supply is suddenly interrupted, the on-duty operators must take timely measures to prevent the water jacket from freezing. For equipment used to transport low-temperature media prone to frost formation, its thermal insulation (cryogenic insulation) facilities must be kept complete and undamaged. 3.2.1.4 For equipment without insulation that is vulnerable to low-temperature cold snaps, temporary cold protection measures should be taken during periods of low temperatures and cold snaps. 3.2.2 Anti-freezing and anti-condensation measures for backup pump equipment: Maintain the smooth operation of the cooling water system and ensure an adequate amount of water; during low temperatures and cold snaps, the water volume should be increased appropriately. Open the inlet and outlet valves of the pump to allow slight backflow of the liquid, with the flow rate being determined by the principle that the liquid does not freeze and the rotor does not rotate in reverse. For equipment with insulation (cold preservation) features, its insulation (cold preservation) layer must remain intact and undamaged. Inspect and turn the machine once per shift; if it cannot be turned or any other problems are detected, measures should be taken promptly. 3.2.3 Anti-freezing and anti-condensation measures for decommissioned pump equipment: Close the inlet and outlet valves of the cooling water, or disconnect the cooling water system from the pump, and drain all water remaining in the pump and its water jacket. Open the cooling water inlet and outlet valves to keep the cooling water system unobstructed. Close the inlet and outlet valves of the pump; if there is internal leakage in the valves, blind plates must be used for isolation. Drain the liquid at the lowest point of the equipment and use air to blow it away, thereby removing all accumulated liquid from within the equipment chamber. If the elevation of the vent point is higher than the lowest point of the pump body, the joint surface must be disassembled to allow drainage. Contact the fitter to loosen the packing seal or mechanical seal. Turn the machine once per shift; increase the frequency of turning it during cold snaps. 3.2.4 Frost and condensation prevention for in-use pipelines: For all pipelines requiring insulation, the insulation layer must be kept intact. Maintain the flow of the medium within the pipes. For pipes that are used intermittently, measures such as maintaining a continuous flow or providing temporary heating should be taken during low-temperature and cold weather conditions. The drain valves at the lowest points of the water system should be drained of water during such periods to ensure that the pipes do not become condensation-prone. During low-temperature and cold wave periods, in the event of a sudden water supply interruption, the water accumulated inside the pipes should be removed promptly, or temporary heating measures should be taken. For all pipes equipped with heat tracing, it is necessary to keep the heat tracing lines unobstructed; at the dead ends or blind spots of the pipes, flow should be directed or condensate should be removed regularly. For pipes prone to condensation, each workshop should determine specific inspection times, carry out more thorough inspections, and include anti-condensation measures as part of the routine inspection tasks. 3.2.5 Prevention of freezing and condensation in deactivated pipelines: For pipelines that are temporarily out of use and prone to freezing or condensation, the steam supply to the heating lines should be increased appropriately to ensure that the fluid within the pipelines does not condense. For pipelines that are shut down or left inactive for an extended period, they must be thoroughly cleaned after being shut down, and checkpoints should be established to ensure that the fluid flowing in the active pipelines does not enter the shut-down pipelines. Records should also be kept. For valves such as drain valves and low-point vent valves that are not in use, during the cooling period, it is necessary to keep them flowing with a gentle flow rate; the amount of flow should be such that no condensation occurs, and the valves should be insulated. 3.2.6 Anti-freezing and anti-condensation measures for towers, containers, and heat exchangers: Remove snow, water accumulation, and ice formations from the equipment in a timely manner. Promptly remove snow and standing water from escalators and platforms. For any equipment that requires insulation, the insulation layer must remain intact; for media that are prone to freezing or solidifying, any heating wires in place must stay unobstructed. For decommissioned towers, vessels, and heat exchange equipment, the inlet and outlet must be isolated, any liquid remaining inside the equipment must be drained completely, and the vent valves as well as low-point drain valves should be opened. Special attention should be paid to draining the liquid stored before and after the main valve in cases where its elevation is higher. The air tanks within the unit must have their condensate drained regularly; during cold periods, this should be done 1-2 times per shift. 3.2.7 Freezing and condensation protection for valves: Cast-iron valves used for various media must be insulated, and this insulation must remain intact. The valves of high-altitude air inlets must be equipped with insulation or anti-freezing measures. When there is liquid remaining in the processing equipment and pipelines, it must be dealt with together with the valves. When freezing is detected in the valve, slowly warm the valve body with warm water to thaw it before attempting to open or close it; forcing it is strictly prohibited. 3.2.8 Freezing and condensation protection for instruments: The instrument air tanks and all air filters should have their water drained once a week, and records of the timing of such drainage as well as any accumulated water should be kept. If water accumulation is detected, the frequency of drainage should be increased. The instrument heating pipelines must remain unobstructed. The instrument heating pipelines must remain unobstructed. Before entering the anti-condensation and anti-freezing period, for pressure-indicating pipelines in which isolation fluid is used, antifreeze must be filled into them; this antifreeze should meet the quality requirements for cold resistance. For circuits where no antifreeze is filled (such as those with air as the medium), water must be drained periodically, and records should be kept. For instrument equipment that is temporarily shut down, anti-freezing and insulation measures must be taken; any accumulated water should be drained, or a system that maintains a small flow of water or steam should be used to prevent freezing while also saving resources. It is also essential to ensure that the equipment is thoroughly purged after water and steam supply is stopped. For all instruments and equipment that are not in use, the water remaining in the pressure guiding pipes must be blown out, the primary instrument valves must be closed, and all pressure guiding pipes must be emptied. 3.3 Inspection, Assessment, and Summary 3.3.1 All relevant departments and workshops within the company should regard anti-freezing and anti-condensation inspections as an important part of their regular inspections and shift handovers, carry out thorough inspections, and address any issues that are discovered promptly. 3.3.2 Each workshop shall complete a summary of its own work on anti-freezing and anti-condensation measures by March 15th of each year, and submit it to the Production Department.