Controlling the cost of consumables

By Hypertherm
Posted on 05/05/2014 in SPARK the blog, Plasma cutting

Next to material handling, consumables can make up the largest portion of operating costs, so anytime you can use fewer consumables you are saving money. A lot of factors can make you go through consumables faster than you need to, but the biggest mistake people make, by far, is changing out their consumables too soon. Some companies have policies that call for automatically discarding plasma consumables after a set number of pierces. At other companies, the policy is to change out consumables at the end of every shift. But the fact is, consumable wear is very application specific and set change out protocols often result in wasted money. Here are some tips to ensure you are changing out your consumables at the right time.

Electrodes. As a rule of thumb, you do not need to change out standard all-copper electrodes until the hafnium pit depth reaches 0.040 to 0.045 inch. On silver electrodes, you can go even longer between change-outs, waiting until the pit depth reaches 0.080” before a change out is needed.

Nozzle. Generally, the nozzle / electrode change out ratio for standard all-copper electrodes is 1-to-1; however for silver electrodes, the ratio is 2- to-1.

Swirl rings. A swirl ring can easily last up to 50 times longer than your other consumables, meaning you don't need to replace your swirl ring until you've gone through up to 50 electrodes. A key tip to getting proper swirl ring life is proper O-ring lubrication. If you don't have enough lubricant, you could wind up chipping or causing other damage when you insert or extract it. On the other hand, too much lubrication can lead to blocked swirl passages and either cut quality problems or improper electrode cooling. Proper technique involves putting a very small amount of lubricant on your fingers, rubbing your fingers together, and then rubbing your finger on the surface of the O-ring.

Shields. The shield should be changed out when they are visibly worn or when cut quality deteriorates. Retaining caps are not actually consumables and can easily last through 50 or more nozzle / electrode change outs.

Hopefully, you've found these tips helpful. Also, don't forget to refer to the owner's manual that came with your system. It contains many more tips just like these!