High-Viscosity Electric Drum Pump

I.High-Viscosity Drum Pump Definition：

High-viscosity electric drum pumps refer to electrically driven, drum-mounted transfer pumps specifically designed for conveying high-viscosity, thick, paste-like, and semi-fluid media. Featuring a compact structure, they can be directly inserted into oil drums, chemical drums, IBC containers, and similar vessels. They feature strong self-priming capability, smooth operation, and suitability for high-viscosity fluids such as resins, greases, adhesives, slurries, and asphalt. These pumps are widely used for transferring, filling, and conveying bulk materials from drums.

II.Core Differences：

1. Medium Conveyance Capability (Core Feature)

• Standard Drum Pumps: Only capable of pumping low-viscosity fluids (water, diesel, dilute solvents). Struggle with slightly higher viscosities, resulting in idling and failure to discharge.

• High-Viscosity Drum Pumps: Specialized for pumping viscous liquids, pastes, and high-viscosity fluids (resins, adhesives, greases, inks, honey, slurries, etc.). Maintain stable conveyance even at viscosities reaching tens of thousands of mPa·s.

2. Structural Principle Differences

• Standard drum pumps: Primarily centrifugal pumps/flexible impellers relying on centrifugal force; high viscosity causes significant resistance and immediate failure.

• High-viscosity drum pumps: Mainstream screw-type (positive displacement) design using sealed chambers to “push” material; higher viscosity improves sealing and suitability for transfer.

3. Flow Rate and Power Characteristics

• Standard drum pumps: Increased viscosity → sharp drop in flow rate.

• High-viscosity drum pumps: Low RPM, high torque, stable flow without pulsation, unaffected by significant viscosity fluctuations.

4. Self-priming and Drainage Capability

• Standard drum pumps: Prone to air locks, failure to prime, and significant residue at the drum bottom.

• High-viscosity drum pumps: Strong self-priming capability, can draw thick media, minimal residue at the drum bottom, ideal for draining viscous materials.

5. Conveying State (Key Advantage)

• Standard drum pumps: Prone to shear damage, foaming, and flow interruption under high viscosity.

• High-viscosity drum pumps: Low shear, pulsation-free, smooth conveying without disrupting material structure (e.g., latex, slurries, colloids).

6. Fundamental Application Differences

• Standard drum pumps: Liquids, low-viscosity materials, rapid pumping, low cost.

• High-viscosity drum pump: Thick materials, pastes, high viscosity, requiring stable discharge/filling.

III.Core Components：

1. Drive Unit: A high-torque, low-speed gear motor serves as the power core for high-viscosity conveying, ensuring sufficient thrust.

2. The pump tube/shaft assembly features an extended pipe structure extending into the barrel, incorporating an internal drive shaft to transmit power to the lower pump head.

3. The core conveying unit (pump head) predominantly employs a screw-type design (primarily single-screw), utilizing a positive displacement mechanism. It advances high-viscosity materials through sealed chambers, representing the key distinction from conventional barrel pumps.

4. Liquid Inlet/Outlet Structure: Discharge port, flow guide chamber, and seals ensure smooth discharge of viscous liquids without leakage.

5. Sealing and Leak Prevention System: Shaft seals, mechanical seals, or packing seals adapt to high-viscosity, high-friction conditions, preventing leakage and resisting wear.

Base / Drum Mounting Fixture: Secures the pump body to the drum opening, ensuring stable operation without vibration.

IV.Classification of Pump Body Structures：

1. High-Viscosity Electric Screw Barrel Pump

• Features a single-screw/eccentric screw positive displacement design that continuously advances media through sealed chambers. Offers low shear, pulsation-free operation, and strong self-priming capability, making it ideal for ultra-high viscosity, paste-like, and viscous materials—the mainstream solution for high-viscosity applications.

2. High-Viscosity Electric Gear Drum Pump

• Features an external or internal gear meshing structure that conveys fluid through gear engagement. Its simple design ensures stable output, making it ideal for clean fluids like medium-to-high viscosity oils, greases, and heavy oils.

3. High-Viscosity Electric Rotary Vane Barrel Pump

• Features flexible impellers or three-lobe rotors that squeeze and push media. Offers broad adaptability for conveying medium-to-high viscosity materials with minimal particulate content, ensuring smooth operation.

4. Classification by Power Supply Type

• 220V Single-Phase Electric Drum Pumps: Suitable for residential/light industrial applications. Portable, versatile, and compatible with standard outlets.

• 380V Three-Phase Electric Drum Pumps: Designed for industrial heavy-duty, high-flow, high-viscosity, and high-power applications. Features high torque and stable operation.

• Explosion-proof power supply (explosion-proof motor + explosion-proof wiring) for flammable/explosive media (solvents, chemicals, oils), compliant with explosion-proof rating requirements.

5. Classification by Installation Method

• Barrel-mouth clamp type (most common): Quick clamp mounts on standard barrel mouths, portable and plug-and-play.

• Flange-mounted type: Flange connection ensures reliable sealing, suitable for permanent fixed positions and equipment integration.

• Extendable hose type (adjustable length): Pump hose length is adjustable to accommodate different barrel heights, IBC containers, and shallow drums.

• Portable handheld type: Integrated handheld structure, lightweight and flexible, ideal for small barrels, temporary transfer operations, and multi-point tasks.

V.Core Selection Parameters：

Viscosity Matching

1. Standard Viscosity Range (Unit: mPa·s)

• General Applicability: 1,000 to 50,000 mPa·s

• Optimal Range: 5,000 to 30,000 mPa·s (Most stable delivery, highest efficiency)

• Ultra-high viscosity coverage: 30,000 to 100,000+ mPa·s (can still convey pastes and semi-fluids)

2. Corresponding Material States for Viscosity Ranges (Visual Reference)

• 1,000 to 5,000 mPa·s: Thick liquids (e.g., heavy oil, thin adhesives, certain resins)

• 5,000–30,000 mPa·s: Highly viscous liquids (e.g., resins, inks, adhesives, honey)

• 30,000–100,000+ mPa·s: Pastes, viscous pastes (grease, thick adhesives, paste-like materials)

3. Core Features (Strongly Correlated with Viscosity)

• Positive displacement screw design → Better sealing and reduced backflow at higher viscosities

• Low speed, high torque → Stable discharge even with high viscosity, preventing stalling and flow interruption

• Low shear, pulsation-free → Preserves structure of high-viscosity colloids, emulsions, and slurries

• Strong self-priming capability → Directly draws high-viscosity media without priming

Material Properties

1. Viscosity Characteristics (Core)

• Suitable for: High-viscosity, ultra-high-viscosity, thick, paste-like, semi-fluid

• Typical range: 1,000–100,000 mPa·s (Optimal range: 5,000–50,000 mPa·s)

• Features: Higher viscosity ensures better seal chamber adhesion, more stable delivery, and reduced backflow/interruptions

2. Flowability and State

• Suitable for: Viscous liquids, pastes, colloids, slurries, latexes, emulsions

• Delivers without high flow rates, via low-shear, smooth pushing that preserves material structure

• Ideal for non-flowing, low-self-flowing, and wall-adhering materials

3. Shear Sensitivity (Core Screw Pump Advantage)

• Suitable for shear-sensitive materials: latex, resins, emulsions, adhesives, food slurries, biopharmaceuticals

• Pulse-free, low-disturbance delivery without foaming, separation, or degradation of viscosity/performance

4. Particle/Impurity Handling

• Conveys materials containing small amounts of soft particles, fillers, or powders (e.g., coatings, inks, mortar slurries)

• Superior particle tolerance compared to gear pumps; less prone to clogging with relatively mild wear

• Not suitable for large hard particles, long fibers, or highly abrasive materials (accelerates stator wear)

5. Lubricity and Medium Types

• Suitable for: Oily, aqueous, neutral, and weakly corrosive high-viscosity materials

• Stable conveyance even for poorly lubricating high-viscosity media (e.g., aqueous adhesives, polymer liquids)

• Can be paired with stainless steel, fluorocarbon rubber, and other materials to handle chemical, food, and pharmaceutical-grade materials

6. Temperature Characteristics

• Medium temperature directly affects viscosity: lower temperatures increase viscosity, making screw pumps more suitable

• Standard application range: -10°C to 100°C (high-temperature applications require optional high-temperature-resistant stators/seals)

Material Selection

1. Core Components in Contact with Media

• Pump casing, pump head, screw, stator, inlet/outlet ports, seals

2. Metal Materials (Pump Body / Casing / Screw)

• Cast Iron (HT200)

• Suitable for: Neutral oils, lubricants, heavy oils, resins, non-corrosive high-viscosity materials

• Features: Low cost, high strength, wear-resistant; limited to non-corrosive applications

• Stainless Steel 304

• Suitable for: Water-based adhesives, emulsions, food slurries, neutral chemical liquids, general corrosion resistance

• Features: Universal corrosion resistance, hygienic, easy to clean; most commonly used

• Stainless Steel 316L

• Suitable for: Weak acids, weak alkalis, solvent-based adhesives, food/pharmaceutical sanitary grade, seawater applications

• Features: Superior corrosion resistance; standard for high-end/chemical/sanitary scenarios

3. Stator / Rubber Material (Determines high-viscosity conveyance and service life)

• Nitrile Rubber NBR

• Applications: Oils, greases, mineral oils, non-polar solvents

• Excellent oil resistance, wear-resistant, most commonly used

• Ethylene Propylene Rubber EPDM

• Applications: Water-based adhesives, emulsions, alcohols, hot water, weak acids/alkalis

• Superior water resistance, alcohol resistance, aging resistance

• Fluorocarbon Rubber FKM / Viton

• Suitable for: Strong solvents, high temperatures, severe corrosion, chemically stable materials

• High-temperature resistance, solvent resistance, long service life

• Food-grade rubber (Silicone / Food-grade NBR)

• Suitable for: Honey, syrups, chocolate, food pastes

4. Seal Material

• NBR: Oils, ambient temperatures

• EPDM: Water-based, alcohols

• FKM: Solvents, high temperatures, severe corrosion

5. Material Selection Logic (Simplified Mnemonic)

• Oil-based → Cast iron / 304 + NBR stator

• Water-based / Emulsions / Food → 304/316L + EPDM / Silicone

• Solvent / Strong corrosion → 316L + FKM (Fluorocarbon)

• Sanitary / Food / Pharmaceutical → Full 304/316L + Food-grade rubber

VI.Use Cases：

1. Industry Applications

Chemical Industry

• Bucket extraction, transfer, and filling of high-viscosity fluids such as resins, adhesives, white latex, polyurethane, inks, coatings, silicone sealants, and sealants.

Oils & Lubricants Industry

• Conveyance of viscous oils including greases, gear oils, heavy oils, asphalt, high-viscosity oils, and refrigeration oils.

Food / Personal Care Industry

• Conveying high-viscosity pastes and colloids such as honey, syrups, chocolate spreads, jams, toothpaste, face creams, shampoos, and conditioners.

Pharmaceutical / Biologics

• Transportation of shear-sensitive, high-hygiene materials like ointments, gels, syrups, extracts, and colloidal solutions.

Rubber / Plastics / Composites

• Handling viscous fluids including rubber slurries, low-temperature hot melt adhesives, polymer melts, and resin solutions.

2. Process Operation Scenarios

• Direct extraction from drums, drum tipping, drum rotation

• Quantitative feeding, batching, and conveying on production lines

• Feeding to filling equipment, discharging from small/medium drums/IBC containers

• Mobile multi-point operations in workshops, temporary material extraction, bottom residue purging

• Precision conveying requiring low shear, no pulsation, no foaming, and no separation

3. Operating Conditions (Core Scenario Logic)

• High-viscosity, thick, paste-like media with poor self-flowing properties

• Shear-sensitive media (must not be agitated, emulsified, or have viscosity reduced)

• Requires smooth, continuous, pulsation-free conveyance

• Plug-and-play operation, portable design, compatible with standard drum sizes

• Materials that standard centrifugal pumps/gear pumps cannot handle or are prone to damaging

VII.Use Cases：

I. Pre-Operation Inspection

• Confirm that the medium, viscosity, temperature, and corrosiveness match the pump model and material.

• Inspect the pump body, screw, stator, seals, and piping for damage, looseness, or leakage.

• Verify that the supply voltage (220V/380V), phase, and explosion-proof rating meet site requirements.

• Ensure the barrel opening is securely fastened and the pump hose is fully inserted to prevent suspension or swaying.

• For initial use or after prolonged shutdown, check the reducer motor lubrication (if required).

2. Startup and Operation Procedures

• Perform a momentary start to verify correct rotation direction, absence of abnormal noises, and no severe vibration.

• After normal operation, observe: continuous discharge without pulsation, no significant air leakage, and no unusual noise.

• Strictly prohibit prolonged dry running (especially for screw-stator designs, which may burn out the stator).

• When conveying high-viscosity materials, reduce flow rate or extend start-up time if suction is poor to avoid overloading.

• Maintain unobstructed discharge during operation; never allow complete outlet blockage causing back pressure (displacement pumps are prone to overload and damage).

• When moving the unit, first shut down and disconnect power before lifting the pump, changing barrels, or adjusting position.

3. Shutdown and Cleaning

• First close the discharge valve (or stop discharge), then shut down and disconnect power.

• For extended shutdowns or before changing media, promptly clean the pump chamber, screw, and piping to prevent material solidification, crusting, or blockage.

• Cleaning media must be compatible with the stator and seals. Do not use highly corrosive or swelling solvents for blind flushing.

• After cleaning, drain thoroughly and store in a well-ventilated area to prevent moisture damage, freezing, or deformation.

4. Safety Precautions

• Do not touch the screw, pump inlet, or rotating parts during startup.

• In flammable or explosive environments, use explosion-proof motors, explosion-proof wiring, and ensure reliable grounding.

• Never force operation beyond rated voltage, temperature, viscosity, or load limits.

• Ensure all piping and connections are secure to prevent splashing, leakage, or injury.

• Immediately shut down and inspect upon detecting abnormal noise, excessive vibration, tripping, or fluid leakage. Never operate with faults.

5. Maintenance and Service Life Considerations

• The stator (rubber sleeve) is a wear part. High abrasion, high temperatures, and strong solvents will shorten its service life.

• Prevent large particles, hard objects, or metallic contaminants from entering the pump head to avoid screw damage or stator tearing.

• For high-viscosity media, operate at low speeds and high torque to reduce load and extend service life.

• Regularly inspect seals, shaft seals, barrel mouth fastenings, and power cord insulation.

VIII.Daily Maintenance：

1. Daily Maintenance (After Each Use)

• Inspect pump body, piping, and shaft seals for leaks, abnormal noises, or unusual vibrations

• Clean residual material from drum opening and pump pipe exterior

• Verify motor temperature is normal with no overheating or burning odors

• When handling media prone to solidification, promptly clean pump head and piping

2. Weekly Maintenance

• Check drum mounting brackets and fasteners for looseness

• Inspect power cord, plug, and switch for damage

• Observe whether discharge is uniform and check for significant flow reduction

3. Monthly Maintenance

• Inspect screw and stator for wear, scratches, swelling, or hardening

• Check seals (oil seals/mechanical seals) for leakage or aging

• Confirm inlet/outlet ports and piping are free of blockages or crusting

4. Quarterly/Semi-Annual Maintenance

• Refill or replace lubricant in gear motor (per motor specifications)

• Completely disassemble and clean the pump head, screw, stator, and pump chamber

• Inspect the drive shaft and coupling for wear or looseness

• Replace visibly aged or worn stator, seals, and other wear parts

5. Long-Term Shutdown Maintenance

• Thoroughly clean and dry the pump interior

• Apply protective oil to rotating parts; apply a small amount of grease to the stator for protection

• Store in a dry, ventilated, non-corrosive environment

IX.Common Problems and Troubleshooting：

1. No discharge or extremely low flow rate

• Medium viscosity exceeds pump compatibility range → Reduce viscosity by heating or replace with higher-power/torque model

• Pump head not fully submerged in liquid → Insert pump fully to ensure suction port is submerged

• Pump head or piping clogged → Shut down and clean pump chamber, screw, and piping

• Severe stator wear or seal failure → Replace stator

• Incorrect motor rotation direction → Reverse the phase sequence of the three-phase power supply

• Air leakage at suction port → Inspect pump tube connections, seals, and drum opening fixation

2. Unstable flow, high pulsation, intermittent suction

• Suction port partially exposed above liquid level → Extend tube depth or reduce discharge speed

• Medium contains excessive air bubbles, poor self-priming → Pump slowly to avoid vortex air intake

• Localized stator wear → Replace stator

• Minor air leaks in pump tubing or joints → Tighten joints, replace seals

3. Motor overload, overheating, tripping

• Excessive viscosity, overload → Heat to reduce viscosity or lower speed

• Closed outlet valve, blocked piping → Check valve, clear piping

• Stator-screw fit too tight (new pump / post-cleaning) → Run briefly unloaded for break-in or inspect assembly

• Abnormal motor voltage (phase loss / low voltage) → Check power supply

• Foreign object in pump head causing seizure → Disassemble and clean; inspect screw/stator damage

4. Pump housing noise, excessive vibration

• Insecure pump mounting, loose barrel connection → Re-tighten clamps/brackets

• Screw bending, drive shaft eccentricity → Straighten or replace screw/pump shaft

• Particle/contaminant ingress → Shut down, disassemble and clean

• Bearing wear, motor failure → Replace bearings or repair motor

5. Leakage at shaft seal or pump pipe connections

• Seal wear/aging → Replace oil seal / mechanical seal

• Improper installation, missing/damaged O-ring → Reassemble, replace seal

• Corrosion exceeds seal compatibility → Replace with corrosion-resistant seal (FKM/EPDM, etc.)

6. Short stator (rubber sleeve) lifespan, prone to damage

• Medium contains hard particles, highly abrasive → Install filtration, control particle size

• Excessive temperature, solvent causes severe swelling → Replace with temperature/solvent-resistant stator material (FKM, HNBR, etc.)

• Frequent dry running → Strictly prohibit dry running, ensure suction inlet is submerged

• Improper assembly, eccentric compression → Standardize screw and stator installation

7. Core Maintenance Points (Can be printed on equipment)

• Strictly prohibit dry running, dry grinding, or outlet blockage

• Stator and seals are wear parts requiring regular inspection and replacement

• Ensure complete immersion of suction port for high-viscosity media

• Clean immediately after use with easily solidifying materials

• Shut down immediately for inspection upon abnormal noise, overload, or leakage