How Low Temperatures Affect Grease Flow and Automatic Lubrication System Design

Low temperature changes the operating conditions of an automatic lubrication system from the reservoir to the final lubrication point. Grease becomes more resistant to movement, pump filling becomes slower, pressure rises during startup, and metering components require more time to complete their cycles.

For industrial equipment operating outdoors, in cold storage facilities, mining areas, ports, wind farms and winter construction sites, the lubrication system must be designed for the lowest operating temperature rather than the average workshop temperature.

At INALUBE, we address low-temperature lubrication by matching the lubricant, pump delivery, divider, injector, controller, filter and pipeline. We do not solve cold-weather pressure problems by simply increasing the pump pressure. We design the complete grease delivery circuit so that the pump can fill, the metering components can operate and every lubrication point can receive the required quantity.

What Low Temperature Does to Grease Flow

When temperature falls, the base oil inside the grease becomes more viscous and the grease offers greater resistance to movement. The resistance appears in four areas of the automatic lubrication system.

A system that operates correctly at 20°C can show a pressure alarm at -10°C even when no component has failed. The design must therefore consider the lowest startup temperature, the grease grade, the longest branch line and the required lubricant quantity.

Low-Temperature Lubrication Problems We Solve

1. The Pump Does Not Fill Correctly During Cold Startup

Cold grease flows slowly from the reservoir to the pump element. If the grease cannot reach the suction inlet quickly enough, the pump delivers an unstable quantity during the first cycles.

For this condition, we check the grease level, suction element, reservoir position, lubricant consistency and filling path. We also select the pump tank capacity and pump element according to the grease consumption and startup conditions.

The LUBElite™ Progressive Lubrication Pump series is available with tank capacities including 2 L, 4 L, 6 L, 8 L and 10 L. The correct tank size provides sufficient lubricant storage for the operating cycle and maintenance interval. Low-level monitoring prevents the pump from continuing to run after the reservoir has reached an unsafe level.

For high-volume grease applications, HeavyXtreme™ provides a 55 kg tank and a listed displacement of 444 cm³/min on the HXP55EHD configuration. This configuration is used when the system requires a larger grease reserve and higher delivery capacity.

2. Starting Pressure Becomes Too High

Cold grease creates higher resistance inside the pump, divider and pipeline. The pressure rises most sharply during the first lubrication cycles after the machine has been stopped for several hours.

We separate a normal cold-start pressure rise from a blockage by observing the complete cycle:

• If pressure rises and then returns after the divider completes its movement, the system is operating through a high-resistance startup condition.
• If pressure reaches the safety setting and remains there, the system has a blocked branch, closed valve, restricted fitting or failed metering element.
• If pressure rises on one branch only, we isolate that branch instead of changing the complete pump configuration.

INALUBE uses the SV Safety Valve to protect the circuit against excessive pressure. We do not increase the safety setting to force cold grease through a restricted line.

3. Progressive Divider Movement Becomes Slow or Stops

A progressive divider operates through a sequence of piston movements. Low temperature increases the resistance required to move the lubricant through each section. If one branch has additional resistance, the divider sequence stops at that position and the pump continues building pressure.

For a low-temperature progressive system, we use PFB, PFM, PFMS or PFG progressive dividers according to the number of lubrication points and the branch arrangement.

The PFB series provides specific monitoring options:

• Visual indicator: allows the operator to observe the piston movement directly.
• Piston detector: sends a signal when the divider piston movement is monitored electrically.
• Different outlet quantities: PFB configurations are available with different outlet counts for different point layouts.

In cold-weather operation, the visual indicator identifies a slow or stopped sequence at the divider. The piston detector allows the controller to identify the same condition without requiring continuous visual inspection.

Our progressive divider solutions are selected according to the required outlet quantity and monitoring method.

4. Single-Line Injectors Take Longer to Reset

A single-line injector must complete the pressure stage, deliver its metered quantity and reset after pressure release. Cold grease increases the resistance inside the injector and branch line, so the reset cycle takes longer.

When the controller starts the next cycle before the injector has fully reset, pressure accumulates in the main line. The result is repeated pressure alarms and uneven delivery between lubrication points.

For this reason, we set the controller interval according to the actual cold-weather cycle time. The controller must give the injector enough time to complete delivery and reset before the next cycle begins.

The SFM-1 single-line injector is available with 2 to 6 outlets, and its listed displacement range is 0.015–0.3 cm³ per outlet. We select the displacement according to the required lubricant quantity at each point. A correct metering quantity prevents the system from forcing excessive grease through a cold and resistant bearing line.

Our single-line injector range is used to control the quantity delivered to each lubrication point.

How We Select the Pump for Cold-Weather Grease Flow

We select the pump according to the lubricant and system architecture. Low temperature does not justify using the largest pump in every application because excessive output increases the pressure load when the divider or branch line has not completed its cycle.

For the GOP10MCPA23 configuration, the listed pump delivery is 160 cm³ per stroke, with a 10 L metal tank, controller and pressure switch. The pressure switch confirms whether the oil line reaches the required pressure during the cycle.

For the FGP series, we use the pump configuration designed for fluid grease rather than applying a standard grease pump to a different lubricant condition.

How We Set the Controller for Cold Conditions

Low temperature changes the time required for grease to reach the final lubrication point. The controller interval must reflect this actual cycle time.

The LUBElite™ Progressive Lubrication Pump series includes controller options with hour- and minute-based interval settings. We use the minute setting when the machine requires frequent lubrication cycles and the hour setting when the cycle interval is longer.

Our setting process is direct:

1. We determine the grease quantity required at each lubrication point.
2. We calculate the delivery time through the divider and longest branch line.
3. We observe the complete divider or injector reset cycle at the lowest operating temperature.
4. We set the controller interval after the system has completed the full cycle.
5. We confirm that the next cycle does not begin while the previous cycle remains pressurized.

Shortening the interval without checking the cold-weather reset time creates pressure accumulation. Increasing the interval without checking bearing demand creates insufficient lubrication. The controller setting must follow the actual machine and grease conditions.

How Pipeline Design Changes at Low Temperature

Pipeline resistance increases when grease becomes more viscous. The effect increases with line length, small internal diameter, sharp bends and excessive fittings.

For cold-weather automatic lubrication systems, we control the following design points:

• We keep the longest branch line as short as the machine layout allows.
• We reduce unnecessary elbows and connection points.
• We use high-pressure hose at moving or vibrating sections.
• We use steel tube or suitable plastic tube according to the installation position.
• We protect the line from external impact and sharp bending.
• We select fittings with a passage that matches the system pipe.

INALUBE supplies plastic tube, steel tube, fittings and high-pressure hose. These components are selected together with the pump and divider because a pressure-rated pump cannot compensate for a poorly routed or restricted branch line.

How Filters Protect Cold-Weather Lubrication Systems

Cold grease already creates higher flow resistance. Contaminated grease adds another restriction inside the pump element, divider or injector.

We select the filter according to the lubricant:

• FO Oil Filter: for oil lubrication systems.
• FL Grease Filter: for grease systems.
• FC Grease Filter: for grease filtration before distribution.
• FR Grease Filter: for protecting the lubrication circuit from contamination.

Before winter operation, we inspect the filter, reservoir, suction element and grease condition. A contaminated filter increases the pressure at the pump inlet and causes unstable filling during cold startup.

Our oil and grease filter configurations are selected according to the lubricant and installation position.

Low Temperature in Dual-Line Systems

Dual-line systems require one main line to pressurize while the other line releases pressure. Low-temperature grease increases resistance in both lines and makes the changeover condition more demanding.

DuoEX™ includes an integrated directional valve, pump outlet and return outlet. The directional valve controls pressure transfer between the two main lines, while the return outlet provides the pressure-release path.

For a cold-weather dual-line system, we check:

• Whether the active line reaches pressure within the required cycle time
• Whether the inactive line releases pressure completely
• Whether the integrated directional valve changes position correctly
• Whether the return outlet and return line are free from restriction
• Whether the dual-line divider receives lubricant on both sides

When the system uses a separate valve arrangement, the XV-250 Directional Valve controls the line changeover and the SV Safety Valve protects the circuit against excessive pressure.

How We Prevent Low-Temperature Lubrication Failure

• We select grease for the lowest operating temperature, not the workshop temperature.
• We match the pump configuration to oil, standard grease or fluid grease.
• We select the divider according to the number of points and branch layout.
• We use PFB visual indicators or piston detectors when progressive movement monitoring is required.
• We select SFM-1 displacement according to the quantity required at each point.
• We set the controller after confirming the actual cold-weather cycle time.
• We install the correct FO, FL, FC or FR filter before contamination reaches the metering components.
• We use suitable steel tube, plastic tube, fittings and high-pressure hose for the installation.
• We verify the safety valve and pressure-release path before winter operation.

Our Engineering Method for a Cold-Weather Lubrication System

When we design or troubleshoot an automatic lubrication system for low temperatures, we request the following information:

• Lowest ambient temperature
• Grease brand, NLGI grade and base oil viscosity
• Number of lubrication points
• Required lubricant quantity per point
• Longest main and branch line length
• Installed pump and divider model
• Required lubrication interval
• Machine startup and operating schedule
• Pressure reading during cold startup
• Photographs of the pump, divider, hose and lubrication points

We use this information to select the pump output, reservoir capacity, divider outlet quantity, injector displacement, filter, valve, controller setting and pipe arrangement.

This process identifies whether the low-temperature fault comes from insufficient pump filling, excessive line resistance, incorrect metering, incomplete pressure release or an unsuitable lubricant.

INALUBE Order & Project Support

INALUBE supplies progressive, single-line, dual-line and multi-line lubrication pumps, together with progressive dividers, single-line injectors, dual-line dividers, controllers, filters, valves and high-pressure piping components.

For a cold-weather project, send us the minimum operating temperature, lubricant information, machine application, number of lubrication points and existing system layout. We will match the pump, divider, injector and accessories to the actual low-temperature operating condition.

Please contact INALUBE for Order & Project Support.

Frequently Asked Questions

Why does grease pressure increase during cold startup?

Low temperature increases grease viscosity and pipeline resistance. The pump requires more pressure to move the same lubricant through the divider, hose and lubrication point.

Should I use a larger pump in a low-temperature lubrication system?

We select the pump according to the grease, line length, delivery requirement and divider cycle. A larger pump does not solve a blocked outlet or an incorrect pressure-release setting.

How does a progressive divider help diagnose cold-weather pressure problems?

The PFB series uses a visual indicator or piston detector to show whether the internal piston sequence has completed. A stopped sequence identifies the blocked divider outlet or downstream branch.

How does the controller affect cold-weather lubrication?

The controller determines the interval between lubrication cycles. We set the interval after confirming the time required for the pump, divider or injector to complete the cold-weather cycle and release pressure.

Which INALUBE pump is used for high-volume grease systems?

HeavyXtreme™ is designed for high-volume grease delivery. The HXP55EHD configuration has a 55 kg tank, a listed displacement of 444 cm³/min and an electric level sensor.