Basic Work and Details of Winter Protection for Skid-Mounted Fuel Stations

With the cold winter fast approaching, all industries are busily preparing for winter. skid-mounted fuel station operators are also racking their brains to cope with this peak season for fuel consumption. Even a slight oversight can lead to operational downtime, mainly because the integrated and highly sealed nature of skid-mounted fuel station makes them susceptible to problems such as fuel condensation, equipment freezing damage, and increased safety hazards in the low-temperature winter environment. Therefore, routine winter maintenance should focus on "anti-freezing, anti-condensation, leak prevention, anti-static, and anti-failure," and should be carried out systematically according to relevant industry standards. Today, Shengding Containers will share the basic work and details of winter protection for skid-mounted fuel stations.

1. Core System: Maintenance of Fuel Storage and Transportation System (Anti-freezing and Anti-condensation are Key)

1.1. Basic Work

• Fuel grade matching and quality monitoring: Ensuring fuel quality is the core and foundation of operating a skid-mounted fuel station. Inferior fuel has significant shortcomings in both anti-freezing and usability, so we must not be penny-wise and pound-foolish.
• Tank insulation and temperature control: This is mainly for areas with extremely low temperatures. In general areas, skid-mounted fuel stations have their own insulation facilities, so additional insulation measures for the tanks are usually unnecessary.
• Pipeline antifreeze and unblocking: Insulation measures for oil pipelines must be properly implemented. Poor antifreeze measures can easily lead to pipe cracks and oil leaks.
• Filter cleaning and anti-clogging: The common method for filter antifreeze is to vent the filter, ensuring it is free of oil.

1.2. Key Details

1.2.1. Oil Management: Preventing clogging and deterioration

• Grade switching: Change to the corresponding grade of diesel in advance according to the local winter minimum temperature (e.g., use -10 or -20 below -10^oC, and -35 below -30^oC). Gasoline can be kept at 92/95, but the distillation range needs to be monitored (to avoid light component volatilization causing starting difficulties).
• Details: Record the lowest temperature daily. If the lowest temperature is lower than the current fuel's cold filter plugging point (CPP) for three consecutive days, immediately switch to a higher grade fuel or add a compliant anti-gelling agent (such as diesel pour point depressant, which must be added according to the fuel ratio to avoid excessive amounts affecting combustion performance).
• Fuel Heating: For tanks with built-in heating devices, set the oil temperature to maintain 5-15^oC (5-8^oC above the diesel CPP); for tanks without built-in heating, use an external electric heat tracing jacket (explosion-proof rating ExdIIBT4 or higher). Direct heating with open flame is strictly prohibited.
• Details: Check the heating device's operating status daily to prevent localized overheating that could lead to fuel deterioration. Regularly (weekly) check the accuracy of the oil temperature sensor.
• Tank Drainage: Drain water from the bottom of the tank before each shift (in winter, water can easily freeze and clog the drain outlet or cause tank wall corrosion). After draining, close the valve and ensure proper insulation (e.g., wrap with insulation cotton and waterproof cloth).
• Details: If the drain outlet freezes, thaw it with hot water (do not use open flame to thaw it). Ensure the valve operates smoothly.

1.2.2. Pipelines and Filters: Preventing Clogging and Leakage

• Pipeline Insulation: Oil pipelines, valves, and joints must be wrapped with flame-retardant insulation cotton (thickness >= 50mm, >= 80mm in low-temperature areas), and the outer layer should be wrapped with waterproof cloth to prevent rain and snow penetration and freezing.
• Details: The insulation layer must be completely covered, with no gaps at joints. Check weekly for damage or detachment, and repair promptly.
• Heat Tracing System Maintenance: For electric heat tracing pipelines, check that the power cord connection is secure (explosion-proof seal intact). Test the heat tracing temperature daily before starting (set at 10-20^oC) to prevent aging or short circuits of the heat tracing cable.
• Details: The heat tracing system must start and stop synchronously with the oil pipeline; prolonged idling is prohibited (to prevent localized overheating).
• Filter Cleaning: Check the pressure difference of the fuel dispenser filter and the oil tank outlet filter daily (normal pressure difference < = 0.05MPa). If the pressure difference exceeds the standard or the oil output decreases, replace the filter immediately (in winter, filter elements are prone to clogging due to impurities and condensed oil).
• Details: Replaced filter elements must be stored properly (to avoid freezing and cracking). The filter element housing must be wrapped with insulation cotton to prevent the internal oil from freezing.

2. Key Equipment: Fuel Dispenser and Pump Unit Maintenance (Prevention of Failure and Seizure)

2.1. Basic Operations

• Preheating the fuel dispenser before starting: This is mainly because there are very precise clearances between the internal components of the oil pump (such as blades and bearings). At low temperatures, the viscosity of the hydraulic oil increases, becoming very viscous. If the pump is started directly without preheating, the viscous oil cannot quickly fill the pump chamber and provide effective lubrication, leading to problems such as a sharp increase in wear, inaccurate metering, and motor burnout.
• Pump and Motor Lubrication: Lubrication of the pump and motor is the lifeline for ensuring the long-term, stable, and efficient operation of fuel dispensers and all rotating machinery. Improper lubrication is one of the main causes of mechanical failure.
• Freeze Protection for Metering Components: Freeze protection for the fuel dispenser's metering components is critical in cold climates. Improper handling can lead to inaccurate metering, equipment damage, or even fuel dispenser malfunction, causing economic losses and safety risks.

2.2. Key Details

2.2.1 Fuel Dispenser Preheating and Start-up

• Before the first start-up each day, activate the fuel dispenser's built-in preheating function (if available) and preheat for 5-10 minutes before starting the pump unit. If there is no preheating function, briefly (30 seconds) jog the motor to expel residual condensed oil from the pipeline.
• Detail: Do not run the pump unit dry for extended periods (poor lubrication in winter can easily lead to motor burnout). After starting, observe the oil pressure (normally 0.2-0.4 MPa). If there are no abnormalities, begin refueling.
• Meter Maintenance: The gears and pistons inside the fuel dispenser's meter must be well lubricated. In winter, replace with low-temperature compatible lubricating oil (such as ISOVG10-22 low-temperature hydraulic oil) to avoid jamming due to low temperatures.
• Detail: Check the meter seals (such as O-rings) weekly. Rubber is prone to hardening and cracking at low temperatures. Replace immediately if leakage is found (use low-temperature resistant (-40^oC) nitrile rubber or fluororubber).

2.2.2 Fuel Nozzle and Hose

• Fuel Nozzle: Check the nozzle sealing gasket and valve opening/closing flexibility daily. In winter, avoid prolonged exposure of the nozzle to the outdoors. When not in use, retract it into the fuel dispenser or cover it with an insulation sleeve to prevent freezing and jamming.
• Detail: If the nozzle freezes, thaw it with warm water before operation. Do not force it or strike it.
• Fuel Hose: Avoid contact between the outer layer of the hose and sharp objects (rubber becomes more brittle in winter and is prone to breakage). Check the sealing clamps at the hose joints daily to prevent loosening and leakage due to thermal expansion and contraction.
• Detail: In low-temperature areas, replace with a low-temperature resistant hose (minimum operating temperature < = -40^oC). The hose length should not exceed 6 meters (excessive length can lead to oil condensation).

3. Safety Protection System: Leakage Prevention, Static Electricity Prevention, and Fire Prevention

3.1. Basic Operations

• Grounding Device Inspection and Maintenance: The "grounding device inspection and maintenance" of the fuel dispenser is a crucial safety issue. It directly relates to preventing static electricity buildup, avoiding lightning strike damage, and ensuring the safety of personnel and equipment.
• Firefighting Equipment Freeze Protection: Freeze protection of firefighting equipment is of paramount importance in winter fire safety management. If fire pipes, hydrants, sprinkler heads, and other equipment fail due to freezing, the consequences in the event of a fire would be unimaginable.
• Leak Detection and Emergency Preparedness: Leak detection is the first line of defense against small problems escalating into major accidents. It is divided into active monitoring and passive monitoring. Active monitoring systems rely mainly on technical equipment and regular inspections to actively search for leak signs. Passive monitoring relies mainly on observation and experience to promptly determine leak phenomena.
• Static Electricity Release Device Inspection: Inspecting static electricity release devices is a crucial safety measure. Its function is to safely conduct away accumulated static electricity before personnel enter hazardous areas, preventing accidents caused by static sparks.

3.2. Key Details

3.2.1 Grounding and Static Electricity Prevention

• Grounding Electrode Maintenance: Check the connection of the grounding electrode of the skid-mounted station and the storage tank to ensure it is secure. Frozen soil in winter may increase grounding resistance. Test the grounding resistance weekly (required to be < =10 Ohm). If it exceeds the standard, a temporary grounding electrode (such as a copper grounding body driven >=1.5 meters underground) needs to be added.
• Details: The grounding lead must be wrapped with an insulation layer to prevent freezing and breakage. Apply conductive paste to the joints to prevent corrosion.
• Static electricity release: Before refueling, the vehicle must be grounded (using a static grounding clamp). Static electricity easily accumulates in the dry winter; ensure the grounding clamp is in tight contact with the metal parts of the vehicle. Do not pat clothing or plug/unplug mobile phones while refueling.
• Details: Check the conductivity of the static grounding clamp daily (resistance < = 10 Ohm using a multimeter). Clean any ice or rust on the clamp promptly.

3.2.2 Firefighting equipment maintenance

• Fire extinguishers: Dry powder fire extinguishers must be stored indoors or in an insulated box (dry powder is prone to clumping and failure when outdoor temperatures are below -20^oC in winter). Check the pressure gauge weekly (the pointer must be in the green zone). If the pointer is below the red line, replace or refill immediately.
• Details: Use winter-suitable fire extinguishers (such as MFZ/ABC type dry powder fire extinguishers, minimum operating temperature < = -20^oC). Do not invert or impact the fire extinguisher.
• Fire sand and fire shovel: Fire sand must be kept dry (to avoid freezing and clumping) and stored in an insulated box. Fire shovels and fire buckets must be checked for integrity and free from freezing or jamming.
• Details: If the fire sand freezes, a small amount of sand desiccant can be mixed in beforehand, or it can be turned over regularly to keep it loose.

3.2.3 Leak Detection

• Daily, apply soapy water to easily leaking parts such as tank flanges, valves, and pipe joints to check for bubbles (leakage is more likely to spread due to low temperatures in winter); for tanks with leak alarm devices, the alarm function must be tested daily to ensure it is working properly.
• Details: If a minor leak is found, immediately stop operation, drain the oil from the relevant pipelines, and then repair; if a large leak occurs, activate the emergency plan, close the main valve, use fire sand to contain the leak, and prohibit open flames from approaching.

4. Auxiliary Systems: Electrical, Drainage, and Insulation Maintenance (Preventing Power Outages and Blockages)

4.1. Basic Work

• Electrical System Freeze and Moisture Prevention: Freeze and moisture prevention of the electrical system is a key aspect of ensuring the safe and stable operation of equipment, preventing short circuits, fires, and extending equipment life.
• Drainage system anti-clogging: The core idea of ​​anti-clogging is "prevention first, combined with treatment." Prevention is the most effective and economical way to avoid clogging. When clogging occurs, measures should be taken in stages according to the degree of clogging.
• Skid insulation and sealing: The main purpose of insulation is to maintain process temperature, prevent energy loss, ensure personnel safety, and meet process requirements. The purpose of sealing is to prevent external media intrusion, prevent internal media leakage, ensure protection level, and achieve environmental protection.
• Emergency power supply inspection: Ensure the normal operation of the emergency power supply so that power can be supplied in time in case of power outage.

4.2. Key details

4.2.1 Electrical system

• Distribution box and cables: The distribution box must be tightly closed to prevent rain and snow from entering and causing short circuits. Desiccants (such as silica gel desiccants) can be placed inside to prevent moisture. The insulation layer of the cables must be checked for damage (they are prone to brittleness in low winter temperatures).
• Details: Test the cable insulation resistance (>= 1M Ohm) with a multimeter every week. Replace immediately if any problems are found.
• Battery Maintenance: If the skid-mounted station is equipped with backup batteries (such as for emergency lighting and alarm systems), ensure the batteries are fully charged. In winter, battery capacity decreases, so the charging interval can be shortened appropriately (e.g., charging once every 3 days) to avoid low-temperature power loss.
• Details: The ambient temperature for battery storage should not be lower than -10^oC. If necessary, install a battery insulation box.

4.2.2 Drainage and Skid Insulation

• Drainage System: The sump and sewage pipes of the skid-mounted station need to be cleaned daily to prevent water accumulation and freezing blockage. A small amount of antifreeze (such as ethylene glycol) can be added to the pipes, or an electric heat tracing device can be installed.
• Details: The sewage pump needs to be started once a week (for 5 minutes each time) to prevent the impeller from freezing and jamming.
• Skid Sealing: Check the sealing strips on the skid roof and side panels. Replace them promptly if they are aged or damaged to prevent rain and snow from seeping into the interior and causing equipment freezing damage. In winter, insulation cotton (thickness >= 100mm) can be laid at the bottom of the skid to reduce the conduction of cold air from the ground.

5. Winter Maintenance Frequency and Emergency Response

5.1. Maintenance Frequency Table

Maintenance Item	Frequency	Key Inspection Points
Oil Temperature and Grade	Once daily	Oil temperature >= cold filter point +5oC, grade appropriate for ambient temperature
Pipeline and Valve Insulation	Once daily	Insulation layer undamaged, no icing
Fuel Dispenser Start-up and Operation	Before each start-up daily	Sufficient preheating, no jamming, no leakage
Grounding resistance test	Weekly	< =10Ohm
Fire equipment inspection	Weekly	Pressure gauge normal, no ice, no damage
Filter element replacement	Every 15 days	Or replace immediately when pressure difference >=0.05MPa
Seal inspection	Monthly	Valve, joint, and meter seals are leak-free

5.2. Common emergency handling

• Pipeline freezing: Thaw in sections with hot water (< =60^oC). Do not use open flame to bake. After thawing, drain the solidified oil in the pipe and check for leaks before resuming operation.
• Equipment jamming: If the pump set or fuel nozzle is jammed, stop the machine immediately and check whether it is caused by freezing or poor lubrication. After handling, run it under no-load for 5 minutes before putting it back into use.
• Oil blockage: If the oil in the storage tank solidifies, start the heating device to slowly raise the temperature (temperature increase < =5^oC per hour). Do not raise the temperature rapidly, which may cause deformation of the storage tank. If necessary, contact a professional to replace the oil.
• Leakage Accident: Immediately shut off the main valve, evacuate personnel, and use fire-fighting sand to contain the leaking oil. Do not use mobile phones or open flames. Call emergency numbers. Repairs should only proceed after the leak is under control.

6. Compliance and Precautions

• 6.1. All maintenance work must comply with the "Safety Technical Requirements for Skid-Mounted Refueling Units" (AQ3002-2021). Unauthorized modification of heating devices, grounding systems, and other critical components is prohibited.
• 6.2. Maintenance personnel must wear low-temperature resistant gloves, non-slip shoes, and anti-static clothing to avoid frostbite or static electricity accidents.
• 6.3. In low-temperature areas, it is recommended to develop a "Winter-Specific Maintenance Plan," clearly defining responsible personnel, maintenance procedures, and emergency response plans, and to organize pre-job training.
• 6.4. Regularly (monthly) contact the equipment manufacturer for professional inspections, focusing on key components such as the heating system, seals, and metering accuracy to ensure long-term stable operation of the equipment.

Through the above systematic maintenance, the impact of low winter temperatures on skid-mounted refueling stations can be effectively reduced, avoiding equipment failures, safety accidents, and economic losses, ensuring operational compliance and stability. Shengding Containers has been engaged in the production, research and development, and sales of skid-mounted fuel station for many years. We have comprehensive and rich experience in winter protection. Please feel free to call us if you have any related inquiries.

Written by

TAIAN SHENGDING METAL CONTAINER MANUFACTURING CO., LTD.

Editor Wang

WhatsApp:+86 152 5486 3111

Email:shengdingtank@126.com