Contributing to Energy Savings. How to Reduce Machine Tool Cycle Time.

What Is Machine Tool Cycle Time?

Cycle time refers to the net time it takes to build a single product unit. For example, if a machine tool produces 30 units in 60 minutes, the cycle time is 2 minutes (= 60 minutes/30 units).

Cycle time is closely related to factors such as product quality, productivity, and even cost. In addition to improving production efficiency, reducing cycle time also leads to cost reductions for things like energy consumption and labor costs.

There are also terms similar to cycle time, such as "tact time" and "lead time." Tact time, referring to the time it should take to produce a single product unit, is calculated as operating time divided by the required units produced. While cycle time is an indicator of production capacity, tact time is based on the number of units ordered by customers or the number of sellable units. Meanwhile, lead time is the time it takes from order to delivery.

The Path to Faster Cycle Times

When considering cycle time reductions, it is important to divide cycle time into cutting and non-cutting time.

Cutting time: The time the machine tool is cutting
Non-cutting time: The time the machine tool is not cutting

Cutting time refers to the time when the workpiece is actually being machined, while non-cutting time refers to the time taken performing non-machining tasks, such as replacing parts, changing tools, and lag in machine operation. It is important to address both of these when making efforts to reduce cycle time.

Also, it is essential to know how much time is spent on each part of the current process. Capturing video of the work actually in progress can also be effective for making sure there is no waste. There are many approaches to reducing cycle time: cutting condition tweaks, work environment revisions, operator training and education, and more. The standard sequence to cycle time reduction is to first determine the current situation, formulate and implement specific improvement measures, and then measure their effect.

Four Ways to Shorten Cycle Time

Of the many approaches to effectively reducing cycle time, here are four that are particularly effective:

Optimize Cutting Conditions

A fundamental step in reducing cycle time is to optimize cutting conditions. Adjust the spindle speed and feed rate, reconsidering the settings for each workpiece. As a general rule, upping the cutting conditions will reduce the cutting time, but it will also increase tip wear. In some cases, this could increase the number of tip replacements, preventing the cycle time from being shortened as expected. Thus, in reducing cycle time, it is important to find well-balanced cutting conditions that comprehensively address time, cost, and other factors.

Reduce Idle Time

Another way to shorten cycle time is reducing idle time, a part of non-cutting time. Look for any waste, overburden, or unevenness in the work process. This may include changing workpiece or tool placement, or working on other tasks while the workpiece is being cut. A thorough 5S (sort, set in order, shine, standardize, and sustain the discipline) can also increase work efficiency and reduce cycle time. Have a look around the workplace and search for any possible room for improvement.

Task Automation

Today's machine tools have various functions, and machinery with advanced automation capabilities has also emerged. Introducing such machine tools will allow for efficient machining with minimal human intervention. For example, a 5-axis machining center can perform multi-face machining to significantly reduce cycle time. In addition, if the machining center is equipped with multiple pallets or a pallet changer, non-stop machining can be performed without stopping the machine for pallet changes.

Improve Operator Skills

Improving operator skills is also paramount. Regular training and education help operators to work more efficiently, reducing errors and inefficiencies. As this will result in a shorter cycle time, also check to see if human factors are the bottleneck.

Deployment of High-Performance Machine Tools as a Shortcut to Reducing Cycle Time

The cutting condition and work process improvements introduced above should reduce cycle time to some extent. However, to this, many manufacturers will say they have already improved worker skills and revised their production process.

For those looking to drastically reduce their cycle time, a shortcut is to deploy new machine tools. While this is a large investment that cannot be decided or implemented immediately, the technology has made remarkable progress in recent years. Compared to conventional tools, the latest machine tools have evolved to be able to machine parts with overwhelming speed and accuracy.

For example, some companies that have newly deployed a Brother Industries "SPEEDIO" machining center have reported cycle time reductions of more than 20% and machining time reductions of up to 40%.

Also, given their environmental performance, SPEEDIO models can be expected to reduce power consumption. If your machine tools are aging or universal machine tools operated by an operator are in use, there should be many advantages to deploying new machine tools.

Cycle Time Reduction as an Important Indicator Directly Linked to Productivity

Cycle time is an important indicator for measuring productivity. Cycle times can be shortened through actions such as optimizing cutting conditions, reducing idle time, and automating operations to increase production efficiency and reduce costs. In addition, with the astounding advancements in machine tool technology in recent years, cycle times can be reduced significantly with the deployment of new machine tools. Although initial investment is required, the burdens of deployment can be alleviated by making use of grants and subsidies from the national and local governments. Determine your own company's challenges, and take appropriate steps to reduce cycle times.