Titanium alloy is more difficult to process than most alloy materials, but choosing a suitable tap is still feasible. Titanium material is both hard and lightweight, making it a very attractive metal suitable for aerospace, medical, and other industries.
However, the material characteristics of titanium alloys pose challenges for many processing factories, and many engineers are also searching for suitable solutions for this material.
Why is titanium difficult to machine?
For example, titanium cannot conduct heat well. When processing titanium, heat often accumulates on the surface and edges of the cutting tool, rather than being dissipated through the parts and machine structure. This is especially true when tapping, as there is more contact between the inner surface of the hole and the tap than between the workpiece and the drill bit, end mill, or other tools. This retained heat can cause notches in the cutting edge and shorten the lifespan of the tap.
In addition, the relatively low elastic modulus of titanium makes it “elastic”, so the workpiece often “rebounds” on the tap. This effect can lead to thread wear and tear. It also increases the torque on the tap and shortens the service life of the tap
To achieve the best results when tapping titanium alloy, please find Taps produced by excellent tap manufacturers, install them in the tapping tool handle, and select appropriate parameters on machine tools with good feed control。
OPT cutting tools provide you with high-quality Taps and worry free after-sales support.
1. Use appropriate speed
The tapping speed is crucial for cutting titanium alloy threads. Insufficient or too fast speed can lead to tap failure and shortened tap life. For entering and leaving threaded holes, it is still recommended to refer to the brand sample and choose a reasonable tapping speed. Although slower than tapping most other materials, this series has been proven to provide the most consistent tap life and maximum productivity.
2. Use appropriate Cutting fluid
Cutting fluid (coolant/lubricant) can affect tap life. Although the same Cutting fluid used for other operations of titanium alloy is an option for tapping, this Cutting fluid may not produce the required thread quality and tap life. We recommend to use high-quality lotion with higher oil content, or better still, use tapping oil.
Tapping extremely difficult to machine titanium alloys may require the use of tapping paste containing additives. These additives aim to adhere to the cutting surface, despite generating high working forces at the interface between the tool and the workpiece. The disadvantage of tapping paste is that it must be manually applied and cannot be automatically applied through the machine’s cooling system.
3. Using CNC machine tools
Although any machine tool capable of processing titanium alloys should be able to effectively tap these materials, CNC machines are the most suitable for tapping titanium. Typically, these newer devices provide rigid (synchronous) tapping cycles.
Older CNC units typically lack this feature. Moreover, the accuracy of these old equipment is also poor, and it is not recommended to tap because tapping is a precision machining process. The selection of equipment is still a bit meticulous, and many sites have also encountered the problem of broken taps due to aging equipment that does not meet the accuracy standards. Therefore, business owners should also pay attention to this issue.
4. Use the tapping tool handle
Taps are particularly susceptible to vibration, which can reduce thread quality and shorten tap life. For this reason, high-performance tapping tool handles should be used to provide a rigid setting. Rigid/synchronous tapping cycles are possible on CNC machining centers, as the rotation of the spindle can be precisely synchronized with the tap feed axis in both clockwise and counterclockwise directions.
This ability enables the production of threads without length compensation in taps.
Some tapping tool handles are designed to compensate for slight synchronization errors that may occur even with the best CNC equipment.
5. Regarding fixtures
To achieve the highest accuracy and repeatability, please check the fixture of your part to ensure that your workpiece clamping system can be fully fixed on the part. This suggestion is particularly important for small batch processing workshops and large batch automobile production plants, which are more likely than ever to encounter work involving titanium workpieces.
Many of these workpieces have thin-walled and complex features, which are conducive to vibration. In these applications, rigid settings are beneficial for each machining operation, including tapping.
6. Plan in advance to determine tapping equipment requirements
The lifespan of a tap depends on many factors, including the ability of the machine tool, the accuracy of feed control, the quality of the tapping tool handle, the grade of titanium alloy, and the type of coolant or lubricant.
Optimizing all these factors will ensure economical and efficient tapping operations.
When tapping titanium, a good Rule of thumb is that for a hole with a depth twice its diameter, 250-600 holes can be drilled each time. Maintain good records to monitor the lifespan of the tap.
Unexpected changes in tap life may indicate the need to adjust key variables. Problems with tapping operations may also indicate situations that have a negative impact on other operations.
OPT cutting tools is manufacturer of Carbide taps, which can provide you with the most competitive price and comprehensive service support.
Post time: Jun-13-2023