Editorial Technical Reference

Rotor with Eccentric Weight

This page explains how Rotor with Eccentric Weight is classified within Electrical Equipment Manufacturing. Technical values and manufacturer relationships are research references; confirm the current specification and supplier evidence for each order.

Technical Definition & Core Assembly

A rotating component with an off-center mass that generates centrifugal force to produce vibration.

View Full Specifications Explore Manufacturing Sources

Product Specifications

Technical details and manufacturing context for Rotor with Eccentric Weight

Definition
The rotor with eccentric weight is the core moving part within a vibration motor. It consists of a shaft-mounted rotor with a deliberately unbalanced mass distribution. When rotated by the motor's electromagnetic field, the off-center weight creates a centrifugal force that causes the entire motor assembly to vibrate. This component directly converts rotational motion into vibrational energy. The rotor is typically made of electrical steel laminations, while the eccentric weight is often a high-density tungsten alloy. The eccentricity, unbalance mass, and rated speed determine the centrifugal force and thus the vibration amplitude. Typical rated speeds range from 3000 to 6000 rpm, with a maximum speed of 8000 rpm. Eccentricity ranges from 5 to 20 mm, and unbalance mass from 0.5 to 5 kg. The resulting centrifugal force at rated speed is between 500 and 5000 N. The rotor is balanced to ISO 1940-1 grades G6.3 to G2.5. The shaft material is typically carbon or alloy steel (e.g., 45# or 40Cr) per GB/T 699 and GB/T 3077, with surface hardness of HRC 40–50 and a zinc-nickel plating for corrosion protection. The operating temperature range is -20 to 80 °C. The rotor diameter ranges from 50 to 200 mm, length from 100 to 500 mm, and weight from 2 to 20 kg. These values are typical ranges; actual specifications must be confirmed with the manufacturer for the specific model. The rotor is used in vibration motors for applications such as material handling, screening, and compacting. It is essential to verify the balancing grade and other parameters against the intended application to ensure reliable operation.
Working Principle
The rotor is mounted on the motor shaft. When electrical power is applied, the motor's stator creates a rotating magnetic field that drives the rotor. Due to the eccentric (off-center) mass attached to or integrated into the rotor, the center of mass does not align with the axis of rotation. As the rotor spins, this imbalance generates a centrifugal force that changes direction continuously, resulting in a periodic shaking or vibrating motion of the motor housing.
Common Materials
Electrical Steel (Silicon Steel), High-Density Tungsten Alloy (for the weight)
Technical Parameters
ParameterTypical rangeNotes & selection driver
Rated Speed3000–6000 rpmOperating range for typical vibration applications
Eccentricity5–20 mmDetermines centrifugal force magnitude
Unbalance Mass0.5–5 kgAffects vibration amplitude
Centrifugal Force500–5000 NGenerated at rated speed
Balancing GradeG6.3–G2.5Residual unbalance limitISO 1940-1
Material45#–40CrCarbon or alloy steel for durabilityGB/T 699, GB/T 3077
Surface HardnessHRC 40–50Enhances wear resistance
Surface TreatmentZinc–Ni platingCorrosion protection
Operating Temperature-20–80 °CBeyond range may affect material properties
Max Speed8000 rpmStructural limit
Diameter50–200 mmOuter diameter range
Length100–500 mmOverall length
Weight2–20 kgDepends on size and material

Ranges are indicative industry figures for RFQ preparation, not a supplier commitment. Confirm every value and standard with the legal manufacturer before ordering.

Components / BOM
  • Rotor Core Part
    Provides the magnetic circuit and structural base for the assembly. Typically made from laminated electrical steel to reduce eddy current losses.
    Material: Electrical Steel (Silicon Steel Laminations)
  • Eccentric Weight Part
    The deliberately off-center mass that creates the rotational imbalance necessary for vibration generation.
    Material: High-Density Alloy (e.g., Tungsten, Brass)
  • Shaft Part
    Central axis for rotation, transmits torque from the magnetic field and is supported by bearings.
    Material: Hardened Steel

Application & selection

Application Fit & Sizing Matrix

Operational Limits
pressure: Atmospheric to 2 bar
other spec: Max rotational speed: 3000 RPM, Vibration frequency range: 10-100 Hz
temperature: -20°C to +120°C
Media Compatibility
✓ Air/gas streams ✓ Dry bulk materials ✓ Non-corrosive liquids
Unsuitable: Highly corrosive chemical environments
Sizing Data Required
  • Required centrifugal force (N)
  • Operating frequency (Hz)
  • Available installation space (mm)

Risk, maintenance & compliance

Reliability & Engineering Risk Analysis

Failure Mode & Root Cause
Bearing fatigue and seizure
Cause: Excessive unbalanced forces from eccentric weight causing cyclic loading beyond bearing design limits, leading to premature fatigue failure or overheating and seizure.
Shaft deflection and cracking
Cause: Continuous high-amplitude vibration due to eccentric mass imbalance, resulting in cyclic stress concentrations at shaft shoulders or keyways, eventually causing fatigue cracks or permanent bending.
Maintenance Indicators
  • Audible knocking or grinding sounds during operation, indicating bearing wear or contact between rotating and stationary parts.
  • Visible excessive vibration or wobble observed at rotor ends or mounting points, often accompanied by increased noise levels.
Engineering Tips
  • Implement strict dynamic balancing procedures during installation and after any maintenance, using precision balancing equipment to minimize residual unbalance forces.
  • Establish regular vibration monitoring with trend analysis to detect early imbalance changes, and schedule preventive maintenance based on vibration severity thresholds rather than fixed time intervals.

Indicative industry ranges for design and RFQ preparation. Confirm the exact figures and applicable standard with the manufacturer before specifying.

Compliance & Manufacturing Standards

Applicable Standards
ISO 1940-1:2003 - Mechanical vibration - Balance quality requirements for rotors in a constant (rigid) state ANSI/ASA S2.19-1999 (R2020) - Mechanical vibration - Balance quality requirements of rigid rotors DIN ISO 1940-1:2004 - Mechanical vibration - Balance quality requirements for rotors in a constant (rigid) state

Quoted from the published standard.

Manufacturing Precision
  • Eccentric weight position: +/-0.5° angular tolerance
  • Bore diameter: +/-0.01mm for interference fits
Quality Inspection
  • Dynamic balancing test to ISO 1940-1 Grade G2.5 or better
  • Hardness testing (Rockwell C) of eccentric weight material
Technical documentation
Request current drawings, revision history, and a signed specification sheet.
Manufacturing capability
Verify equipment lists, process limits, capacity, and representative production evidence.
Inspection readiness
Confirm test methods, calibrated equipment, sampling plans, and traceable reports.
Supplier transparency
Check the legal entity, factory address, ownership, certifications, and direct contacts.

Compare the published product scope and source details, then include your specifications and quantity in an enquiry.

Manufacturers of Rotor with Eccentric Weight

Manufacturer profiles associated with Rotor with Eccentric Weight.

Sourcing Rotor with Eccentric Weight from China?
Tell us your specification and target quantity — we will match it against manufacturer records and come back with the factories that fit.
Request manufacturers We manufacture this

Explore company information and manufacturing capabilities, then discuss the scope of your project with a relevant supplier.

Buyer enquiry

Request manufacturing insight for Rotor with Eccentric Weight

Ask for use case, specification boundaries, supplier type, and RFQ preparation information for this product.

Where it goes
Straight to the CNFX editorial desk, and to the manufacturer if this product is linked to a claimed profile. Nothing is broadcast to a supplier list.
Your details stay here
We do not sell or rent enquiry data, and we do not add you to a mailing list. Used only to answer this request.
No commission, no middleman
CNFX is a directory. We take no cut of any order and never negotiate on a supplier's behalf.
What to include
Share your product specifications, quantity, destination and target delivery date.

Your business information is used only to process this request.

Thank you! Your message has been sent. We'll respond within 1–3 business days.
Sorry, we couldn't send your message. Please try again, or email us at [email protected].

Frequently Asked Questions

What is the function of the rotor with eccentric weight?

It converts rotational motion into vibrational energy by generating centrifugal force due to an off-center mass, causing the motor to vibrate.

What materials are typically used?

The rotor core is usually made of electrical steel (silicon steel), and the eccentric weight is often high-density tungsten alloy. The shaft may be carbon or alloy steel.

What are the typical operating parameters?

Rated speed is typically 3000–6000 rpm, eccentricity 5–20 mm, unbalance mass 0.5–5 kg, and centrifugal force 500–5000 N. These are ranges; confirm for your model.

How should I verify the balancing grade?

The balancing grade is specified per ISO 1940-1, typically G6.3 to G2.5. Verify with the manufacturer that the rotor meets the required grade for your application.

Data basis: editorial classification, named public sources where available, and source-reviewed manufacturer records. See the editorial policy.

Related equipment

Applied To / Applications

This component is essential for the following industrial systems and equipment:

Vibration Motor
View system integration details

Industrial Ecosystem & Supply Chain Structure

Data Basis

Editorial classification, named public sources where available, and source-reviewed manufacturer records.

Preliminary Technical Classification
This page supports structured research, RFQ preparation, and supplier evaluation. It does not replace buyer-led supplier qualification, standards review, or technical approval.

Compiled and source-reviewed by the CNFX editorial team. Each manufacturer above links to the page on that company's own website where the product is listed, with the date we checked it. How we source and review · Page last updated 12 October 2026

Need to Manufacture Rotor with Eccentric Weight?

Compare manufacturer profiles with relevant product and process capability.

Create Manufacturer Profile Contact Us
Previous Product
Wire Tensioning System
Last Product
Get QuotesChat