Sunnen K20-NM55 CBN Honing Stones Set 6 pcs 220 Grit

Description

Product Overview

The Sunnen K20-NM55 CBN honing stone set is a meticulously engineered collection of six individual bars, each featuring a 220-grit cubic boron nitride (CBN) surface. Designed specifically for Sunnen AK20, K20, and KL series mandrels, these honing bars deliver a level of precision that meets the demanding tolerances of aerospace, automotive, and high‑performance machining environments. The CBN material offers exceptional hardness, thermal stability, and resistance to wear, ensuring that each bar maintains its abrasive characteristics over extended production runs. With dimensions of 4 x 1 x 1 inches, the bars are compact enough to fit into standard honing fixtures while providing sufficient surface area for efficient material removal. The set is packaged in a durable, reusable container that protects the bars from contamination and damage, extending their service life and reducing overall operational costs.

Usage

These honing stones excel in applications where surface finish and dimensional accuracy are critical. Typical use cases include the final honing of cylindrical components such as shafts, pistons, and bearing housings, where a surface roughness of Ra 0.2 µm or better is required. The 220‑grit grade provides a balanced blend of material removal rate and finish quality, making it suitable for both medium‑roughing and fine‑finishing stages. Operators can employ the bars in conventional honing machines, CNC‑controlled honing centers, or manual hand‑held setups, depending on production volume and precision needs. The CBN coating tolerates high spindle speeds and aggressive feed rates without glazing, allowing for faster cycle times. Additionally, the stones are compatible with a variety of coolant systems, including oil‑based, water‑based, and synthetic lubricants, which helps to dissipate heat and flush away debris, further enhancing surface integrity.

Why Choose Us

Choosing the Sunnen K20‑NM55 CBN honing stone set means investing in a product backed by decades of abrasive technology expertise. Sunnen’s reputation for quality control ensures that each bar meets stringent dimensional and material specifications, reducing variability and the risk of unexpected downtime. The CBN coating is applied using a proprietary bonding process that guarantees uniform grain distribution and optimal adhesion, resulting in consistent performance across the entire set. Our after‑sales support includes technical assistance, replacement parts, and a comprehensive warranty that covers manufacturing defects. By selecting this set, manufacturers benefit from reduced tool change frequency, lower scrap rates, and improved overall equipment effectiveness (OEE). The combination of superior material properties, precise engineering, and dedicated customer service makes this product a reliable choice for high‑value machining operations.

Key Features

• High‑grade CBN coating delivers exceptional hardness and wear resistance for long tool life.
• 220‑grit size provides a versatile balance of material removal and fine surface finish.
• Compact 4 × 1 × 1 in dimensions fit standard honing fixtures, simplifying setup.
• Compatible with a wide range of coolants, reducing heat buildup and improving finish quality.
• Backed by Sunnen’s technical support and warranty for reliable after‑sales service.

FAQ

What types of mandrels are compatible with this honing stone set?

The set is specifically engineered for Sunnen AK20, K20, and KL series mandrels, but it can also be used on similar cylindrical components that require a 220‑grit finish.

Can these stones be used with water‑based coolants?

Yes, the CBN coating is chemically inert and works effectively with water‑based, oil‑based, and synthetic coolants, providing flexibility for various machining environments.

How often should the honing bars be replaced?

Due to the durability of the CBN coating, the bars typically last for thousands of honing cycles. Replacement is recommended when a noticeable drop in abrasive performance is observed.

Is there a recommended spindle speed for optimal performance?

For most applications, spindle speeds between 2,000 and 4,000 RPM provide a good balance of material removal and surface finish. Adjust speed based on workpiece material and desired outcome.

What warranty does Sunnen offer on this product?

Sunnen provides a one‑year limited warranty covering manufacturing defects, along with access to technical support for installation and operational guidance.