HSS Co5 Cobalt Twist Drill Bits

HSS Co5 Cobalt Twist Drill Bits are high-speed steel twist drills with cobalt incorporated into the tool material rather than applied as a surface coating. The reference configuration uses HSS Co5 with a nominal 5% cobalt content, making this series suitable for drilling stainless steel and selected alloy steels where cutting heat needs to be taken into consideration.

The drill uses a 135° split point, cylindrical shank and right-hand cutting direction. Its DIN 338 jobber-length format fits conventional drilling setups and provides a straightforward specification for routine workshop and engineering applications.

For procurement, the actual workpiece grade and hardness should be confirmed before selecting the drill. Stainless steel is a broad material category, and different grades can behave quite differently during drilling. RONGKE can review the material, hole depth, machine setup and cooling method when confirming the appropriate configuration.

Key Facts at a Glance

Technical Specifications

Common reference sizes in mm. Final material, geometry, dimensions and availability are confirmed with the quotation.

Why Choose HSS Co5?

Cobalt Is Part of the HSS Material

The defining feature of this HSS Co5 Cobalt Twist Drill Bits are its cobalt-alloyed HSS substrate. With a nominal 5% cobalt content, the cobalt is incorporated into the tool material itself rather than being applied as a coating. This makes the drill materially different from a conventional unalloyed HSS twist drill.

A Practical Choice for Stainless Steel

Stainless steel can generate considerable heat during drilling, particularly when cutting conditions, workpiece hardness or cooling are not well matched to the operation. The HSS Co5 configuration is intended for stainless-steel drilling and other suitable applications where elevated cutting heat is a consideration.

Suitable for Selected Alloy Steels

The application is not limited to stainless steel. Suitable alloy steels can also be considered, but the exact grade and hardness should be provided when ordering. This avoids treating all alloy steels as though they have the same drilling requirements.

Material Selection Matters

A cobalt drill is not automatically the right choice for every metal or every difficult drilling operation. The actual material grade, hardness, hole depth, machine rigidity and cooling conditions should be considered together when selecting the tool.

135° Split Point & Core Tool Design

The 135° split point is another defining feature of the reference configuration. By shortening the central chisel edge, the split point provides a more defined cutting geometry at the center of the drill and supports drill entry into the workpiece.

The drill uses a cylindrical shank for conventional tool holding and right-hand cutting for standard drilling rotation. Together with the HSS Co5 substrate and DIN 338 jobber-length format, these features give buyers a clear configuration to specify when sourcing cobalt HSS twist drills.

The reference configuration is supplied according to the agreed material, geometry and dimensional requirements. Any application requiring a different point, length or other non-standard configuration should be confirmed with RONGKE before production.

Where HSS Co5 Cobalt Drills Fit

Stainless Steel Components

This is the primary application for the HSS Co5 configuration. It can be considered for drilling stainless steel components where the selected drill geometry and cutting conditions are appropriate for the specific grade.

Alloy Steel Parts

Selected alloy steels can also be machined with HSS Co5 drills. Because alloy composition and hardness vary considerably, the workpiece grade should be provided when requesting a quotation.

General Engineering Components

The HSS Co5 Cobalt Twist Drill Bits can be used for suitable engineering parts where a cobalt-bearing HSS twist drill is preferred. Diameter, hole depth and machine conditions should be checked before selecting the final specification.

Workshop and Fabrication Work

For workshops handling stainless steel parts and general fabricated components, standard diameters provide a convenient option for regular drilling requirements. RONGKE can also evaluate non-standard dimensions when a standard drill does not meet the application.

Match the Drill to the Workpiece

Choosing a cobalt drill should start with the workpiece rather than the drill diameter alone.

Stainless Steel Grade Provide the exact material designation whenever possible. “Stainless steel” alone does not tell enough about the material's machining characteristics.

Material Hardness Hardness should be considered when determining whether the HSS Co5 configuration is suitable, particularly for alloy steels or heat-treated components.

Hole Diameter and Depth The required diameter and usable drilling depth should be checked against the available drill dimensions. Deeper holes may also require closer consideration of chip evacuation and cooling.

Cooling Method State the coolant method when requesting a quotation. Cooling conditions are particularly relevant when drilling materials where cutting heat is a concern.

Machine Rigidity and Tool Holding Machine stability, chuck condition, runout and shank fit can all influence drilling results. These details are useful when evaluating a demanding application.

For special alloys or tight hole-tolerance requirements, RONGKE recommends confirming the complete machining conditions before finalizing the tool specification.

HSS Co5 Drill Supply for Different Machining Requirements

RONGKE supplies standard HSS Co5 twist drill configurations for regular purchasing requirements, including commonly requested diameters. When the application involves a particular stainless steel grade, unusual hole dimensions or a specific machine setup, buyers can provide the machining details for further evaluation.

For customers who need more than a standard catalogue size, RONGKE also develops and manufactures non-standard cutting tools. Diameter, length, point geometry and other requirements can be discussed according to the actual application. Sample trial cutting is available when practical testing is needed before a larger order.

This approach allows the purchasing process to start with a standard drill where appropriate, while still leaving room for an application-specific tooling solution when the standard configuration is not enough.

Before You Place an Order

To help RONGKE confirm the right HSS Co5 configuration, please provide the workpiece grade and hardness, required drill diameter, hole depth, machine type, cooling method and order quantity. If there is a particular requirement for the point geometry, length or shank, include that information with the inquiry.

For stainless steel, providing the exact grade is especially useful. It gives the technical team a better basis for assessing the tool configuration rather than making a selection from the material category alone.

FAQ

What does HSS Co5 mean?

HSS Co5 refers to high-speed steel containing a nominal 5% cobalt as an alloying element. The cobalt is part of the HSS substrate and is not simply a surface coating.

Why are HSS Co5 twist drills used for stainless steel?

HSS Co5 is intended for stainless-steel drilling and applications where elevated cutting heat is a consideration. The suitability of the drill still depends on the stainless-steel grade, hardness, hole dimensions and cutting conditions.

What is the purpose of the 135° split point?

The 135° split point shortens the central chisel edge and provides a defined cutting geometry at the center of the drill. It is part of the reference configuration for this HSS Co5 series.

Can HSS Co5 drills be used for alloy steel?

They can be considered for suitable alloy steels, but the exact material grade and hardness should be confirmed first. Different alloy steels can have significantly different machining requirements.

Is cobalt a coating on the drill?

No. In an HSS Co5 drill, cobalt is an alloying element within the HSS tool material. The reference product should not be confused with a conventional HSS drill that has simply received a cobalt-containing surface coating.

Can RONGKE supply customized HSS Co5 drills?

Yes. RONGKE develops and manufactures non-standard cutting tools in addition to standard products. For a customized requirement, provide the workpiece grade, hardness, diameter, hole depth, machine setup and required quantity so the configuration can be evaluated.

What information should I provide for a quotation?

Please provide the workpiece material and grade, hardness, drill diameter, hole depth, cooling method, machine type and quantity. Any special requirements for the drill point, length or shank should also be included.