FAIZEAL · PRODUCT PAGE COPY · ENGLISH

Inner Magnetic Rotor for Magnetic Drive Couplings

Product detail page copy for the FAIZEAL website (fzmag.com). British English, B2B industrial register, engineering-focused, prepared for direct publication.

Product: Custom Inner Magnetic Rotor, NdFeB or Sm₂Co₁₇ arc magnet assembly　·　Use: Google organic and paid landing page　·　Status: client review draft

Summary

The inner magnetic rotor is the torque-carrying core of a seal-less magnetic drive coupling. This page sells it the way buyers evaluate it: matched pole geometry, verified flux uniformity, dynamic balance to ISO 1940, and materials selected against temperature and corrosion duty. The copy closes with an OEM enquiry route for drawing-based customisation.

1　SEO Title and Meta Description

Use one title for the page, one meta description for the search snippet, and keep the keyword set stable across the category and product pages.

Primary Title (recommended)

Custom Inner Magnetic Rotor for Magnetic Drive Couplings — Zero-Leakage NdFeB / SmCo Arc Magnet Assemblies, FAIZEAL

Secondary Title

Precision Inner Rotor Assemblies for Magnetic Couplings — Multi-Pole NdFeB Magnets, Dynamically Balanced and Bonded, OEM/ODM

Meta Description (155 characters)

FAIZEAL custom inner rotors for magnetic couplings: sintered NdFeB or SmCo arc magnets, zero-leakage multi-pole flux, precision balance. OEM from CAD.

Page URL

How to Calculate Transmitted Torque in Coaxial vs. Axial Magnetic Couplings - Faizeal

Target Keywords

Inner magnetic rotor, magnetic coupling rotor, magnet coupling assembly, magnetic drive coupling manufacturer, NdFeB arc magnets, custom magnet rotor, seal-less pump magnet, ODM magnetic assembly.

2　Product Overview

The inner magnetic rotor is the torque-carrying core of a magnetic drive coupling. Inside the coupling, this rotor sits on the drive shaft and carries a ring of high-energy permanent magnets, arranged in an even multi-pole pattern. Its external magnetic field couples through the containment shell to the outer rotor, transmitting full-rated torque with no mechanical contact and no shaft seal, so the pump or machine stays hermetically sealed while the drive keeps running.

The FAIZEAL inner rotor shown here pairs a precision-machined stainless steel body with sintered NdFeB or Sm₂Co₁₇ arc segments, each ground to a matched pole-arc geometry and bonded over its full contact surface. The result, verified under magnetic viewing film, is a clean and symmetric multi-pole flux distribution with no visible leakage bands, which is the direct signature of balanced torque transmission, low vibration and maximum coupling efficiency.

Every rotor is manufactured in our Ningbo factory as a custom component. Send us your coupling drawing, air gap, pole count and torque target, and we will engineer the rotor to match: magnet grade, pole geometry, bonding method, balancing grade and surface treatment are all specification variables, not catalogue fixed values.

3　Key Features and Benefits

Seven features decide whether an inner rotor survives its duty. Each one below is written as a specification decision you can put in a purchase order, not as an adjective.

Zero-leakage torque transmission

Because torque crosses the containment shell magnetically, there is no shaft penetration to seal and therefore no leak path. The inner rotor's field pattern is engineered for full flux linkage across the operating air gap: every pole of the inner ring faces a matching pole of the outer ring, which maximises transmitted torque per unit of magnet volume and keeps eddy-current losses in the shell low.

Premium magnet materials, correctly specified

Arc segments are cut from sintered NdFeB (high Br grades for maximum torque density, SH, UH and EH temperature classes for elevated service temperatures) or from sintered Sm₂Co₁₇ where the application demands 250 to 350 °C operation, strong corrosion resistance, or a stable Br in changing temperature fields. We select the grade against your working temperature, demagnetising stress and cost target, and we state the grade openly on the drawing rather than as a generic neodymium magnet.

Matched arc geometry, ground in sets

Each segment is wire-cut or diamond-ground to a common pole-arc and chamfer specification, then assembled as a matched set so that every pole presents the same angular width and radial height. Uniform poles are what make the flux film look even; uneven poles show up later as torque ripple, vibration and noise in the driven machine.

Verified flux uniformity

The multi-pole field of every assembly is inspected under magnetic viewing film. The film image on this page is from a production rotor: evenly spaced, sharply bounded poles with symmetrical transition zones and zero flux leakage. We treat the film check as a go or no-go inspection gate, not as a marketing picture.

Dynamic balancing to ISO 1940

Rotors are dynamically balanced after final assembly, to G2.5 as standard and to G1.0 where the driven equipment demands it. Balancing at rotor level protects the bearings and seals of the complete coupling and is essential for higher-speed pump applications. Concentricity of the magnet ring to the bore is held within a stated runout (TIR) limit on the drawing.

Full-surface bonding with engineered retention

Magnets are bonded with a high-temperature structural adhesive over the full contact surface, which eliminates air gaps behind the magnets and prevents fretting. Where duty cycles involve frequent torque reversals or elevated temperature, we add mechanical retention in the form of a machined retaining shoulder, a shrink ring or pinning, so that the magnet ring cannot migrate even in an upset condition.

Corrosion protection matched to the duty

Standard magnet protection is a triple-layer Ni-Cu-Ni plating; epoxy coating is used where chemical resistance matters, and parylene conformal coating is available for thin-profile, high-specification applications. The rotor body is machined from stainless steel, in 304, 316 or a precipitation-hardening grade, to suit the pump-side environment. Coated samples are validated by salt-spray testing for marine and chemical duties.

4　Technical Specifications

The table below gives the standard specification envelope. Final values are fixed on the customer drawing, because every rotor is custom.

Table 1　Inner magnetic rotor — standard specification envelope

Specification notes

Magnet grade and pole count are selected against the required torque, air gap and working temperature. Where a customer's existing coupling is supplied as a sample, we reverse-check the magnet grade and remagnetisation state before quoting.

Operating temperature limits refer to the magnet itself; the bonding system and the coating must be selected to match the same temperature, which is why we quote the assembly rather than the magnet alone.

Flux film inspection verifies pole uniformity and freedom from leakage at assembly level. Rated torque is validated at coupling level on the complete inner and outer rotor pair.

5　Industry Applications

Seal-less chemical process pumps. The classic duty: hazardous, volatile or corrosive fluids where a single drop of leakage is unacceptable and the inner rotor runs fully enclosed behind the containment shell.

Pharmaceutical and fine chemical pumps. Sterile and high-purity circuits where hermetic containment supports clean-in-place regimes and product integrity.

Petrochemical and refinery transfer pumps. High-specification hydrocarbon duties combining temperature, pressure and emissions-control requirements.

Food, beverage and dairy pumps. Hygienic magnetically driven pumps where the rotor materials and coatings must suit washdown and cleaning chemistry.

Semiconductor and vacuum equipment. Magnetically driven mechanisms that must not introduce particles, lubricants or outgassing into the process volume.

Marine and offshore systems. Seawater-cooled and submerged drives where rotor coatings are salt-spray validated.

HVAC and general industrial pumps. Standard magnetically driven pump ranges where the rotor is the maintenance-free heart of the seal-less design.

Test rigs and precision instruments. Coupled drives needing low vibration and repeatable torque transmission without mechanical contact.

6　OEM and Customisation — Send Us Your Drawing

FAIZEAL is a manufacturer, not a trading company. Inner rotors are built to customer specification as standard practice, not as an exception.

Custom dimensions and envelope. Manufactured directly from your CAD drawing, in STEP, DWG, DXF or PDF, or from a physical sample.

Custom magnetic design. Pole count, pole-arc, magnet grade and axial length engineered against your torque, air gap and temperature requirements; we can run the coupling calculation with you at the design stage.

Custom materials and protection. Stainless body grades, NdFeB or Sm₂Co₁₇ magnets, bonding and retention methods, and coating systems matched to your fluid and temperature.

Custom quality gates. Balancing grade, runout limits, flux film acceptance criteria and documentation packs agreed before production.

Request a quotation

7　Notes for Publishing

The two images on this page are a production rotor and its flux film. Keep them together: the film image is technical evidence of pole uniformity, and buyers of magnetic couplings read it that way.

Pole count and torque are deliberately expressed as ranges because the rotor is custom. If a standard range page is created later, insert the actual values from the drawings before publication.

The specification envelope in the table follows the terminology already agreed for FAIZEAL documents: kilograms-force or newtons for force, newton metres for torque, G2.5 and G1.0 to ISO 1940 for balance, and TIR for runout.

Prepared for FAIZEAL · Ningbo FAIZEAL Magnetic Technology Co., Ltd. · fzmag.com · Product page copy, inner magnetic rotor · 2026