What is plasma?
Before we explain how plasma cutting works, let’s define what plasma is first. Plasma, in simple terms, refers to the fourth state of matter. Matter can either be a solid, a gas, or a liquid at one time. When the matter is exposed to heat, it can change from one state to another based amount of heat. Let’s take water, for instance. It will change from ice, which is its solid-state, to water, which is its liquid state when the temperature around it goes up to a certain level. When the heat goes up further in water, it will change from liquid state to steam – its gas state.
Steam can further break down when exposed to high heat levels to become plasma, which is iodized and can conduct electric currents. To transfer energy to any conductive compound from a power supply, a plasma cutter uses gas that conducts electric currents. This leads to a faster cutting process, which is cleaner than oxy-fuel.
What is Plasma Cutting?
So, how does a plasma cutter work? Going by how Webster defines it, plasma is “a group of charged particles … that have equal numbers of positive ions and electrons that flows like gas and can also conduct electricity …” Think of it as a gas stream that is heated with an electric current. You can also think of it as a state where all of the electrons from every atom are not just orbiting but flowing from atom-to-atom. Cutting metal using plasma cutting is pretty straightforward no matter what’s going on inside a plasma stream. The constrict stream of electricity that flows through the gas is a small orifice. The steam will be moving very fast and very dense, leading to melting and blowing through metals easily. This is known as a plasma torch. A copper nozzle is used to constrict the gas stream with the arc flowing through it in plasma cutting torches.
The arc shifts from an electrode in the torch to the cut conductive compound. This is referred to as a ‘transferred arc.’ Although not used for cutting, we have ‘non-transferred’ arcs that jump from the electrode back to the nozzle in some systems. Objects that conduct electric currents, such as mild steel and stainless steel, are cut using plasma. Although there are also other types of metals and alloys that conduct electric currents, such as brass, copper, cast iron, and many others, it is hard to cut them using high-quality edges. This is due to their melting points.
Plain carbon, stainless steel, titanium, and nickel alloys are among the wide range of metals that are cut using plasma arcs. In the past, this metal cutting method was made to cut materials that couldn’t be cut properly using the oxy-fuel method. In most cases, the plasma torch is moving while the sheet or object to be cut is not. It is common for a cutting table to have several cutting torches since, compared to the price of tools, the cost of the plasma torch is low.
What is the sensor?
In modern living, sensors play a vital role. A computer mouse has optical sensors; a smartphone has touch sensors and many other types of sensors. But what are sensors? A sensor is defined as a device that is used to measure physical inputs from its around an object. After that, it will relay the gotten info into data that can be read by another device or a human. Most sensors convert raw data into electronic data. Others like the glass thermometer are quite simple and relay readings into visual data. Sensors are used in various areas of life to gauge distance, detect smoke, measure and control pressure, measure temp, and many other uses.
While using pricey cutting tools such as laser cutters, or plasma cutting machines, the user has to be very careful. It is easy to collide processes when the operator is not keen enough to wait for a new program. Besides that, protecting expensive tools from damages is vital when a device stops working.
Best sensors to protect Plasma cutting systems
1. 800 Series Flow Switches
The calibration done for the standard 800 Series flow switch meters allows it to measure water at 25 °C or 77 °F. Due to the different velocities of fluids, this flow meter is used to measure water alone. If you use it with other fluids, it will affect its accuracy. Proteus designs and delivers devices with specific calibration and is made for certain heated fluids.
Pros of Owning and using an 800 Series
- It measures flow range of about 0.2 to 227 LPM / 0.05 to 60 GPM
- Liquid temperatures should be about -40 to 140°C / -40 to 284°F.
- The pressure to 1724 kPa / 250 psi
- Calibrated 0–5 VDC output
- Relay trip point – 16 preset settings
- Compact design
- 5-year warranty
2. 8000XHT Series – Extreme-Temperature Flow Meters
For accurate and reliable flow readings of liquids and fluids that transfer the heat of about -60 °C to 200 °C, the Extreme High/Low Temperature 8000XHT Series flow meters will work out very well. Proteus has what it takes to produce high-temperature world-class meters calibrated to meet market demands.
Pros of using an 8000XHT Series
- These types of flow meters are designed to handle fluids of up to 200 °C
- Measure flow ranges from 0.95 to 60 LPM / 0.25 to 16 GPM
- Produce full-scale accuracy of 3%
- -60 to 200 C / -76 to 392 °F optional temperature measurement
- Accounts for fluid viscosity effects and operating temperature due to specialized calibration
- Digital signal processing and stability boost accuracy.
- 0–5 VDC or 0–10 VDC and 4–20 mA outputs > Standard NEMA 4X / IP66 enclosure
- OEMs customization option available
- 5-year warranty
3. 8000 Series Liquid Flow Meters
Proteus 8000 Series flow meters give accurate, cost-effective, rugged, reliable heat transfer readings of fluids and liquids from -40 to 90 °C. For liquid temperatures of 150 °C, Proteus provides customized versions that are adapted to use with liquids of that temperature. With a built-in relay that is used to shut down or sound an alarm, expensive tools are protected before getting damaged.
Pros of setting up an 8000 Series
- Flow ranges from 0.2 to 227 LPM / 0.05 to 60.0 GPM
- Flow range accuracy of 3%
- The customized version can measure the fluid flow rate of 150°C and above!
- The standard models can handle liquid temperatures of from -40 to 90°C
- The digital signal processing accuracy and stability are enhanced.
- Customization available for OEMs
- AutoAlarm™ automatic alarm trip point setting feature
- 0–5 VDC or 0–10 VDC and 4–20 mA outputs
- Standard NEMA 4X / IP66 enclosure
- 5-year warranty
You can check Innovative Flow Management Products
For over 30 years now, Proteus has offered value addition in flow meter products for our customers. Some of the sectors that use our flow meters, flow-switches, and sensors include medical, solar, and automotive. Products from Proteus are used to protect thousands of robotic welders, induction furnaces, and other applications that include plasma cutting and high-power laser systems. Custom options are available for all our products to suit different fields.
Proteus has an ISO 9001 certified quality system
Here are a few more topics that you shouldn’t miss:
Benefits of Rebuild Kits for Flow Sensor
Interesting Facts about Liquid Flow Meters and Sensors
Why is Liquid Flow Sensors Relevant?
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