Hertel K017157AS Spiral Point Tap 5/16-24 Unf Left Hand

Product Description

The HERTEL K017157AS is a left-hand spiral point tap designed for cutting internal threads in a 5/16-24 UNF thread form. Manufactured from high-speed steel with a bright, uncoated finish, this plug-chamfer tap uses 2 flutes and a spiral point geometry to push chips forward ahead of the cutting zone, making it well suited for through-hole tapping applications. The H3 thread limit holds tight tolerances to produce a 3B class of fit. It weighs 0.06 pounds and is sold as a single unit. Licensed machinists, tool-and-die makers, and maintenance technicians working in metalworking shops or industrial maintenance environments are the primary users of this tool.

This tap is used in through-hole tapping operations where a left-hand thread is required, such as assemblies that must resist loosening under specific rotational loads. The 5/16-24 UNF thread size and plug chamfer make it appropriate for general-purpose threading in ferrous and non-ferrous metals where fine-thread engagement is needed. It is commonly found in machine shops, production facilities, and field maintenance settings requiring left-hand thread repairs or original fabrication work.

Key Features

• Left-hand thread direction for applications requiring reverse-thread fastening
• Spiral point geometry pushes chips forward, ideal for through-hole tapping
• High-speed steel construction provides durability across a range of workpiece materials
• Plug chamfer with 3-5 thread lead for general-purpose thread starting
• H3 thread limit ensures consistent 3B class of fit tolerances
• Bright, uncoated finish for use across standard lubricated tapping conditions

Compatibility

Designed as an OEM-style replacement or standard production tap for through-hole applications requiring a 5/16-24 UNF left-hand internal thread with a 3B class of fit.

Installation Notes

This tap is installed using a standard tap wrench, tapping head, or CNC rigid tapping setup configured for left-hand rotation. Secure the workpiece firmly before beginning and apply cutting fluid appropriate for the workpiece material throughout the operation. Do not reverse the tap with excessive force if resistance is felt, as this can cause breakage; back off incrementally to clear chips. Threading operations should comply with applicable shop safety standards and machining best practices.