Product Overview
Cast high-chrome grinding balls are the workhorse of fine grinding. In cement clinker and raw-meal circuits, and in mineral plants that grind to a fine product, wear rate - not the price on the invoice - decides what a tonne of media really costs you. Chrome-alloy cast balls hold their shape longer, so your charge stays graded and your grind stays stable.
We supply cast grinding balls from 15 mm to 120 mm across the low-chrome, medium-chrome and high-chrome families, up to roughly 26% Cr. The right chrome level comes down to your mill, your feed and how fine you grind; we help you pick it rather than pushing the most expensive ball in the catalogue.
Kennen Steel is a China-based steel trading house and first-tier mill agent with three decades in the trade and a vetted network of source mills. We are not a factory - we match your specification to the mill that casts it best, then handle testing, packaging and export paperwork as one package. Typical orders serve cement works and mineral plants across East Africa, Southeast Asia and the Middle East.
Key Advantages
High chrome for a lower wear rate
High-chrome cast balls (up to around 26% Cr) resist abrasion far better than plain or low-chrome media, which means less media consumed per tonne ground and fewer top-up charges. The exact wear rate is confirmed per batch - we would rather quote it against your ore than promise a figure that only holds in someone else's mill.
Consistent hardness, batch after batch
Hardness is controlled by chemistry and heat treatment, then checked on samples from every batch. Surface hardness typically sits in the HRC 58–65 region depending on chrome level; the band is confirmed per heat and stated on the certificate.
The right chrome level for the duty
Low-chrome for lighter, lower-abrasion duty, medium-chrome for the middle ground, high-chrome where abrasive feed and fine-grind targets put wear resistance first.
Sizes to build a graded charge
15–120 mm, so you can hold the size distribution your mill design calls for instead of topping up with whatever single size is in stock.
Technical Specifications
| Item | Specification |
|---|---|
| Product Name | Cast High-Chrome Grinding Balls (chrome-alloy cast grinding media) |
| Process | Alloy casting followed by controlled heat treatment (quenching and tempering) |
| Diameter | 15–120 mm (15 / 20 / 25 / 30 / 40 / 50 / 60 / 70 / 80 / 90 / 100 / 110 / 120 mm) |
| Chrome Families | Low-chrome / medium-chrome / high-chrome (up to approx. 26% Cr) |
| Chemical Composition | Confirmed per grade (C, Si, Mn, Cr, P, S) |
| Surface Hardness | Approx. HRC 58–65 (chrome-level dependent; to be confirmed) |
| Core Hardness | Confirmed per batch |
| Impact Toughness (Ak) | To be confirmed per grade |
| Breakage Rate | Target ≤ 1% (to be confirmed per grade and diameter) |
| Wear Rate | Confirmed per batch / application |
| Diameter Tolerance | Confirmed per size |
| Standard | Manufactured to the mill's standard; certificate per batch |
| Packing | Steel drums or 1 t bulk bags |
| Certificate | Mill test certificate per batch (chemistry, hardness, impact) |
Grades, chrome level, hardness bands and packing are confirmed against your mill type and feed before the order is placed.
Step-by-Step Manufacturing Process
- Charging and melting - the melt is brought to the required chemistry, with the chrome level set to the grade being cast. Chemistry is checked before the pour.
- Casting - the melt is poured into ball moulds to form the ball at the target diameter, so sizes are set at the mould rather than by cutting.
- Shakeout and cleaning - balls are knocked out, gates and flash removed, and each piece inspected for surface defects before heat treatment.
- Heat treatment - a controlled quench and temper cycle hardens the ball and relieves internal stress, tuning the balance between hardness and toughness.
- Testing - surface hardness, impact toughness, drop-ball and metallographic checks are run on samples from each batch.
- Finishing and packing - final visual inspection, then packing into steel drums or bulk bags for export.
Quality Assurance & Certificates
- Mill test certificate per batch - chemical composition, hardness, impact toughness
- Drop-ball test for breakage resistance
- Metallographic (microstructure) verification on request
- Third-party inspection available on request (SGS, BV, Intertek)
- Manufactured to the mill's standard; certificate per batch
- Each shipment is checked against the agreed specification before it leaves, so what lands matches what was ordered
Core Applications
- Cement clinker and raw-meal grinding - the main use for high-chrome media
- Fine mineral grinding in gold, copper, iron ore and polymetallic plants
- Coal and power-station mills
- Chemical and industrial mineral grinding
- Secondary ball-mill charges and regrind circuits
FAQ
Should I use cast or forged grinding balls?
Cast high-chrome balls suit finer, lower-impact grinding where wear rate drives the cost - cement and fine mineral duty are the classic cases. Forged balls generally hold an edge on larger diameters and higher-impact duty, with better toughness and a lower breakage rate. Tell us your mill type, feed size and target grind and we will point you to the right one.
What is the difference between low, medium and high chrome?
The chrome content in the alloy, and with it the wear resistance and hardness. Low-chrome serves lighter duty, medium-chrome the middle ground, and high-chrome (up to roughly 26% Cr) the most abrasive fine-grinding work. The exact grade is matched to your feed and grind target.
What hardness can you guarantee?
Surface hardness typically sits in the HRC 58–65 region depending on chrome level. The exact band is confirmed per heat and stated on the batch certificate.
Can you match a specific ball charge size distribution?
Yes. Tell us the mix of diameters your mill design calls for - for example 40 / 60 / 80 mm in a given ratio - and we will supply to that distribution.
Do you provide test certificates?
Yes. Each batch comes with chemistry, hardness and impact results, and third-party inspection can be arranged if required.
How do you pack for export?
Steel drums or 1 t bulk bags, strapped and containerised. Packing is confirmed against the destination and handling conditions before shipment.
