“Foundations” for Machine Tool Success

It has been said that every successful thing in life happens because it was built on a strong foundation. It might be a company that continuously delivers exceptional products and services. Or, an individual who is highly respected for their character and contributions to their community in an effort to make it a better place for everyone to live.

The same can be said for your machine tools as well. In order for them to perform at their full design capability and deliver many years of profitable service, one of the key elements is something that is built and put in place before the machine arrives. This is the “foundation” on which the machine will sit. There have been many documented cases where shops have seen accuracy and performance issues with their equipment shortly after installation. Upon a through engineering review it was found to be that the machine’s foundation was inadequate for the performance characteristics and design of the machine that it was being asked to support. Don’t let this happen to you! Let’s take a look at a few of the best practices for designing and building a good foundation.

Machine Tool Site Selection

Before you determine if a space in your factory is suitable for your machine have you looked into the following?

• Is the site in an area that is subjected to vibrations from other equipment?
• Will the machine be subjected to direct sunlight?
• Is the site located in an area that is subject to high moisture exposure?
• Will the site be exposed to dust and other contaminants once the machine is installed?
• Is the site subject to ambient temperature changes such a locations close to exterior walls and windows?

Design Recommendations

For some machines – especially precision machine tools – foundation design should begin as follows.

• Obtain a foundation reference drawing and guidelines from the machine builder.
• Hire a licensed engineer to test the sub soil conditions at the foundation site to ensure it has the load bearing capacity for the foundation concrete weight as well as the weight of the machine tool and its workholding/tooling capacities.
• Hire an experienced Design and Build contactor that has a proven track record with precision machine tool foundations.
• If the foundation is a below floor design with a metal surround deck make sure to leave a sufficient gap between the deck and the machine base. They should never touch as this can cause problems with leveling and alignment.

Construction Recommendations

To ensure satisfactory results it is best practice to follow these guidelines when constructing your foundation.

• Concrete construction should be of a single pour. Forms for the holes of the foundation bolts should be fixed to the rebar reinforcement before the concrete is poured.
• Allow ample space in each core to pour the grout that will hold the foundation bolts in place.
• If using corrugated piping for your foundation bolt core, be sure that it is of the non-galvanized type. Galvanized piping will react to the grout and not allow it to adhere to the core.
• Always use a cement based grouting mortar that is of the non-shrink type for best results
• Never connect your foundation to existing building foundations such as one for a building column that supports a crane rail.
• Always isolate your foundation from other elements with a Styrofoam isolation barrier of the appropriate thickness for your machine size.
• Use a quality concrete that is rated at 5000 lb./in.² resistance

What’s covered above are the basics that will give your machine tool a solid structure to sit on, providing an environment that is conducive to your success. Keep in mind that I’ve provided a comprehensive list, and the complexity of foundation design and build can vary greatly depending on machine size, type and construction.

Can you add to this list? Feel free to comment below and share your experiences. Okuma America and our team of distributor professionals stand ready to help you determine the foundation requirements that are appropriate for your machine.

Gary Snow is Principal Engineer, Okuma America Corporation.