Why Powermax?

By Hypertherm
Posted on 02/02/2017 in SPARK the blog, Plasma cutting

Here's a question we get a lot...why should I buy a Hypertherm Powermax® instead of a (sometimes much) less expensive competitive air plasma system? It's a good question and, as consumers, we often ask the same question when out shopping. After all, no one wants to waste hard earned money.

There are a number of reasons why Hypertherm Powermax systems can cost more than other air plasma systems, but generally the reason comes down to three things: (1) engineering, (2) manufacturing, and (3) reliability.

ENGINEERING
Hypertherm has lots of engineers focused on cutting technology. In fact, we believe we employ more engineers than any other plasma manufacturer out there. At least 10 percent of Hypertherm Associates work in engineering. These engineers, who like all Hypertherm Associates own a stake in the company, work hard. They are responsible for countless inventions and technology breakthroughs impacting everything from power output to the amount of time your consumables last. A few Hypertherm inventions (all patented or in the process of being patented) include:

Auto-Voltage™ — Allows you to use a wide variety of input voltages with no manual linking of any kind.

Boost Conditioner™ — Makes it possible for the system to grab the maximum amount of power from any given line including low-voltage and generators.

Advanced Axial Swirl Ring — Perfectly aligns the long vented nozzle and swirl ring near the tip of the electrode to ensure the correct amount of gas flow and optimal consumable life.

Coaxial-assist™ Jet — Uses a unique design to split the air into plasma gas and a secondary gas that coaxially surrounds the plasma arc. This increases the energy density and velocity of the arc.

Conical Flow™ — Further increases the energy density of the arc for better cut quality with little dross.

Then there’s CoolCore®, CoolFlow™, LongLife®… Plus a host of specialty torches and consumables. For example, Hypertherm is the only company making a straight hand torch or a four foot long plasma cutting torch. And we’re the only ones making extra-long consumables (called HyAccess) for cutting in hard to reach areas.

Our engineers have also optimized the power output of our systems. Most people think a 40 amp system from Manufacturer A will produce the same amount of power as a 40 amp system from Manufacturer B, but as explained in our Amps vs. Watts and Amps vs. True Cutting Power posts, that isn't true. In reality the true power of a system is the amperage multiplied by the load voltage capacity of the plasma power supply. In other words: Amperage x Voltage = Wattage.

A plasma power supply that can produce a higher wattage will have more power regardless of the amperage. A 30 amp system like Hypertherm's Powermax30 XP can deliver more power than a 40 amp system. A 45 amp system like the Powermax45 can provide more power than a 60 amp system. Don’t let anyone tell you otherwise. This extra power—or load voltage—is what controls the length of the cutting arc and the thickness of material you can cut.

Now let's talk about the torch and consumables. Almost every low-cost system out there uses a universal torch made by another company using 30 year old technology invented by Hypertherm.

Hypertherm on the other hand engineers our torch and consumables hand-in-hand with our power supplies. Our torch isn't universal. It is designed with the power supply, tested with the power supply, and optimized to work best with the power supply. This is important because plasma torches develop an ionized gas arc between the electrode and nozzle then add DC energy to that electrical arc to increase the temperature up to 25,000 degrees Fahrenheit. This 25,000 degree arc is then forced through a copper orifice, which incidentally melts at 1,100 degrees, to make the arc perfectly round and increase its velocity.

The majority of torches found on the low-cost imports (and indeed Hypertherm torches from 30 years ago) will give you between 120 and 250 starts before it is time to change the electrode and nozzle. The newest torch designs from Hypertherm will generally achieve between 900 and 3,000 starts on one nozzle and electrode. This is possible because of the engineering advances mentioned above. The air flow that goes through the swirl ring and enters the inner chamber of the nozzle creates a swirling, hot gas centrifuge that slings the cooler (and heavier) molecules of gas to the outside of the nozzle bore. This is good because this cooler gas serves as a shield to protect the copper nozzle from melting.

Another item we try to protect from heat is the tiny pin sized piece of hafnium at the tip of your electrode. Hafnium melts at around 3,000 degrees. During cutting, when the plasma arc is at 25,000 degrees, this hafnium is in molten state. When you stop cutting and release the trigger on a non-Hypertherm system, a small piece of this molten hafnium comes out of the nozzle orifice. This loss of hafnium adds up. After a number of cycles, you're going to notice really poor cut quality (more angularity, more dross, etc.) Wait long enough and you’ll eventually see a green flame; a sure sign your hafnium is completely gone and you’ve hit copper.

While no one can stop hafnium from melting during the plasma cutting process, Hypertherm is able to slow down its loss by slowly ramping up and then ramping down the air pressure and power. The ramp-up at the start of cutting minimizes thermal shock to the electrode as it goes from room temperature to 3,000 degrees. At the end of the cut, we do the opposite and ramp down the air pressure and power so the hafnium has time to re-solidify.

When you do the math you will see that while the imported power supplies will cost you less at the outset, once you factor in the cost of consumables, an imported system will wind up costing you more. Our Consumable Bargains and Consumable Life posts have more on this.

MANUFACTURING
Whew. All that and we’re just now getting to the second reason Hypertherm systems cost more: manufacturing. Hypertherm is the only company in the world making plasma systems in the United States. Following lean and six sigma practices, our manufacturing team works with our engineers to ensure Hypertherm systems are built to the correct design specifications in a careful, methodical manner. We source the best components we can find, follow strict quality control guidelines, and double check all our work. Consumables like our electrode and nozzle are precision machined to tolerance levels eight times narrower than a human hair. Hafnium is precisely inserted in the very middle of the electrode tip using a Hypertherm-specific robotic system engineered and built by us.

RELIABILITY
It requires a ton of design and long term testing to ensure that what you’ve designed will really last. At Hypertherm, we ensure the reliability of our systems in two ways. First, we use a design for lean approach which is basically a fancy way of saying we design our systems with fewer parts (and wires and screws…) so there’s less chance of something breaking.

The second thing we do is test the heck out of all our systems. Our reliability lab does things like connect the system to a power source producing 10 percent more amperage than the unit is designed for. It then subjects the units to humidity levels 30 percent higher than what the unit will ever see. The lab techs monitor each system closely and when the unit fails (as is expected) they dissect it to figure out what went wrong, send it back to engineering, then back into our “torture chamber” for more testing. All told, this process takes between 10 and 18 months

In addition, we also conduct what we call “shake and bake” tests. These tests subject our units to extreme levels of vibration, oscillation, temperature, and dust. Then there’s the dreaded "drop test" when someone climbs a ladder and purposely drops a Powermax to see how if fares. Yes, this makes for long new product development cycles, but very reliable products.

So to summarize, when you choose to buy a Powermax air plasma, you are buying advanced engineering, careful manufacturing, and industry leading reliability. Whether those things are worth the extra money is obviously a personal decision but hopefully this explains why Hypertherm systems may sometimes cost more.

Posted in SPARK the blog, Plasma cutting
Tagged with Powermax