Welcome to the Mirage Machines Portable Performance Blog

How to select the right machine tool for flange serration

 flange facing machine checklist-1

Whether you’re a seasoned on-site machinist, a maintenance manager, or a procurement professional, if you know the key things to consider when selecting a machine for flange serration you’ll be well equipped to make the right choice, whether it’s for a one-off project, or to bolster your fleet of equipment for future projects. Below we’ve listed the commonest questions our technical specialists ask customers who are interested in getting a flange facer for serrating flanges.



Do you require an internally or externally mounted flange facer machine?

  • Internally mounted flange serration machines are available in a wide range of sizes for flanges up to 3 meters diameter. These are usually supplied with a separate base and adjustable legs for clamping inside the flange bore.
  • Externally mounted flange serration machines should be used whenever it’s not possible to clamp to the flange’s inner diameter. These external machines are generally one piece and faster to set up than the internal mount models. 

What is the OD (outside diameter) of the flanges you will be machining?

An obvious consideration – but you should also bear in mind that if you ever need to create a serrated flange finish across the flange bolt holes, the required facing diameter will be greater.

What type of flange is being machined? e.g. Raised Face, Flat, RTJ, Heat Exchanger, Compact Flange, Lens Ring?

This will determine if you require additional options or accessories.

What material are the flanges? are there any coated faces or bores in Stellite, Inconel or others?

If flanges are hard faced you may need specific tool inserts.

Are there any physical restrictions to the working environment?

If you have a specific job in mind - check for obstructions, bolts etc.

If you intend to mount the machine internally, is there enough parallel bore to mount the assembly?

This is required to allow the jaws at the end of the legs to clamp securely. If not possible, consider an externally mounted machine.

Are there any client specific tolerances or surface finishes to consider?

You may want to create spiral serrated finishes with various ‘grooves per inch’ in line with ASME guidelines, so make sure you check the technical details before committing to buy. Many machines are supplied with more than one lead screw - enabling a wider range of finishes to be achieved.

Do you require a spares kit with the machine?

For a little extra cost make sure you’re ready when it is time to replace lost or damaged fixing bolts, tool holders and motor spares.

Do you intend to machine heat exchanger flanges?

To do this you’ll need to ask for a heat exchanger mounting kit - which secures the flange facing machine’s base using expandable toggles inside the tubes. If machining the back faces of the heat exchanger, you’ll also need a Back Facing Kit.

If machining RTJ grooves do you need a measuring kit?

These are often machine specific, and worth requesting with your quotation.


Machining needs vary by project. But hopefully some of the above will help you if you need to procure a portable machine for flange serration. Taking just a little extra time to list your requirements before you request a machine will prevent costly errors - saving you time, money and helping you achieve great results when machining on-site.

If you need equipment for an on-site machining project, visit our resources section or get in touch with your regional contact here

Download The New Buyers Guide

Recent Posts