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  • Preparing a Second-Hand Tank for O₂ Storage

    Preparing a Second-Hand Tank for O₂ Storage

    When acquiring a second-hand steel tank for high-purity O₂ service, internal corrosion, residual oils or grease, and flash-rust pose safety and performance risks. This post outlines a validated method for bringing those tanks into service readiness, adapted for oxygen storage applications. It combines degreasing, rust-removal/conversion and proper preparation for subsequent filling.

    Why Internal Cleaning Matters

    Steel storage tanks that have been used, modified or idle may contain:

    • Internal rust or flash rust (even thin iron-oxide layers)
    • Residual oils, grease or machining/welding waste
    • Moisture or contaminants that could accelerate corrosion or pose ignition or reactivity risks under enriched-oxygen conditions

    These issues are especially significant for O₂ service: any hydrocarbon film, moisture or loose scale inside the tank increases hazard potential. Ensuring the internal surface is clean, dry, and in a stable state is key.

    Step 1: Degrease & Remove Oils

    Before any acid or rust-conversion step, remove oils, grease or organic contaminants. For example:

    • Use a degreasing wash such as Simple Green or an industrial-grade alkaline degreaser, fill/flush the tank, agitate, and rinse.
    • A coin operated car wash is a good place to gain access to a space to blast an old tank clean.
    • Ensure that after degreasing the water rinsing out is clean and that no foaming or oil film remains.
    • Dry as much as practical before rust-treatment.

    This step matters because residues interfere with later acid conversion, may trap moisture, and under oxygen service could lead to reactivity. In industrial rust-bath literature it is consistently recommended to degrease first. – ChemCafe

    Step 2: Rust Conversion / Removal

    Once the interior is degreased and rinsed, proceed with a phosphoric-acid based treatment (or a product such as Ospho) to convert or remove internal rust.

    Phosphoric Acid Method

    Warning: Phosphoric acid can burn skin and eyes and will damage surfaces if spilled. Use proper PPE and mix it safely by adding acid into water. The instructions here are based on common industry practice but may not be suitable for every situation. Always confirm the procedure fits your equipment and follow your local safety and disposal rules. You’re responsible for your own safe handling and use.

    Simple Dilution Guide for 85% Phosphoric Acid

    These mixes are designed for 1 gallon of working solution.
    Always add acid into water, not the other way around.

    Make as many gallons as required for your size tank. We recommend mixing up 1/10th to 1/20th the volume of your tank as phosphoric acid solution.

    Heavy Rust / Scale

    Purpose: Thick rust, scale, long-neglected tanks.
    Strength: Stronger mix.

    • Start with 1 gallon of water
    • Then add 2 cups of 85% phosphoric acid

    This gives a strong solution appropriate for stubborn internal rust.

    Moderate Rust

    Purpose: Noticeable rust, but not heavily scaled.
    Strength: Medium.

    • Start with 1 gallon of water
    • Then add 1 cup of 85% phosphoric acid

    Good all-around cleaning strength for most used tanks.

    Light Rust

    Purpose: Uniform surface rust, no pitting.
    Strength: Mild.

    • Start with 1 gallon of water
    • Then add ½ cup of 85% phosphoric acid

    Great for cleanup after storage or when a tank has a light orange film.

    Flash Rust Only

    Purpose: Tanks that were clean but flash-rusted during drying.
    Strength: Very mild / conversion-only.

    • Start with 1 gallon of water
    • Then add ¼ cup of 85% phosphoric acid

    Application of Phosphoric Acid Solution to Convert and Inhibit Rust

    With your solution prepared, proceed with the following:

    • Fill the tank partially (e.g., ~1/10th–1/20th of internal volume) with the solution, plug the valves and ports, and rotate/tumble the tank so the solution wets the entire internal surface. Time depends on severity (e.g., 15–30 minutes).
    • Drain the solution (capture for reuse or disposal per local regulation).
    • Hot-water rinse thoroughly until the tank walls feel warm and the internal surface is well rinsed.
    • Dry immediately, using clean, dry, oil-free air (or dry nitrogen) and rotate/roll the tank as drying proceeds. Inverting the tank to blow moisture down can help speed the process up.
    • Inspect interior visually (and optionally with borescope) for clean grey/white surface or residual dark phosphate film first
    • After drying, install valves and fittings.
    • Finally, purge or flush the tank with inert or service gas (e.g., ambient air or N₂) a few times (fill-dump cycles) to remove residual moisture/air before O₂ fill.

    Commercial Version of the DIY Phosphoric Acid Treatment: Ospho
    Ospho is a commercial rust-converter product that uses phosphoric acid plus wetting-agents and extenders. It converts rust to iron phosphate rather than aggressively dissolving it. Key features:

    • According to manufacturer, it “safely dissolves bleeding rust … converts iron oxide to iron phosphate … produces a dry, powdery grey/white surface when cured.” ospho.com
    • It is best applied after cleaning off loose scale, dirt, grease.

    Step 3: Optional Film-Forming/Corrosion-Inhibitor Compounds

    Compound O Oxygen Safe Rust Inhibitor
    Oxygen Compatible Rust Inhibitor

    After degreasing and rust conversion/removal, some operators apply a thin film corrosion-inhibitor or amine-based treatment. One compound class worth noting is diethanolamine (DEA / DEOA) — sometimes referenced generically as “Compound O” in industrial metal-processing contexts.

    • Diethanolamine is a secondary amine/diol which is used industrially as a corrosion inhibitor and surfactant in metal-working fluids. Third Coast Chemicals
    • Its function: it can form a protective amine film on cleaned metal surfaces, reduce re-oxidation (flash rust) during storage, and improve wetting/adhesion of further coatings.
    • If used, it must be compatible with oxygen service: the film must be free of oils, solvents or hydrocarbon residues – Compound O is, but not all DEA compounds are.
    • The procedure would be: after acid rinse and hot‐dry, apply a very light amine film (in controlled manner), then purge/flush before O₂ filling. Note: you must verify the film does not present an ignition hazard under high partial-pressure O₂ and is compatible with your system’s compatibility standards.
    • Because DEA is also flagged with safety/health concerns (it is listed as “possibly carcinogenic to humans” by IARC). Wikipedia
      Thus its usage must follow strong safety and compatibility review.

    Step 4: Final Drying & Preparation for O₂ Service

    Given the service is O₂ storage, the final drying, inspection and inert-purge steps are arguably the most critical.

    It’s important to note:

    • After cleaning and rinsing, the tank interior must be absolutely dry. Preferably use dry nitrogen or dry shop air that is filtered for oil/moisture and verify dew-point if possible.
    • Valve installation should use O₂-cleaned fittings, lubrication, and adhesives (if any) appropriate for O₂ service (no hydrocarbon oils) – Loxeal 85-86 is a great option.
    • After valve install, perform a purge/fill dump cycle with inert or ambient gas (e.g., three fill-to-service pressure and dump) to remove any remaining moisture or contaminants.
    • A thorough visual inspection with lighting or borescope of the interior surface to confirm no loose scale, no orange rust, no residual film that could react under O₂ service.
    • Document the entire preparation: date, tank ID, degreasing solution used, acid concentration, rinse volumes, drying time, purge cycles, inspection findings. This supports traceability and safety efforts.

    Summary

    By incorporating all four steps — degrease, rust-remove/convert, optional corrosion-film/amine treatment, and final drying/purge — you can bring a second-hand steel tank into a condition suitable for O₂ storage.

    Key takeaways:

    • Always remove oils/grease first.
    • Use phosphoric acid or an equivalent rust-converter (like Ospho) to stabilise rust.
    • Consider an amine-based film (e.g., DEA/Compound O) only if fully compatible with O₂ service.
    • Drying, purge, inspection and trace documentation are highly suggested for O₂ service safety.

    For help with your Oxygen System design and more expert advice, contact us today.

    Get Started
  • Fixing The Pressure of Oxygen Concentrators for Powering a Flameworking Torch

    Fixing The Pressure of Oxygen Concentrators for Powering a Flameworking Torch

    You’ve got your torch, propane, and concentrator – but that flame isn’t behaving like you know it should. Your oxygen supply is lacking but you’re not quite sure what’s wrong. Having the right oxygen supply is not only helpful, it’s absolutely required for the longevity of your torch face.

    This situation is all to familiar, particularly to flameworkers who transition from a small torch and oxycon setup, to a larger torch.

    “What works with a small torch, often leaves something to be desired on a larger burner.”

    Comparing a Nortel Red Max torch face to a Minor, you can see how much more space there is for oxygen and fuel to exit the face of a Red Max.

    It’s a simple matter of geometry. A larger torch face has more openings and so requires more flow to produce the same flame velocity and characteristics. This important contributing factor to productive and efficient lampwork is what our core offering of oxygen technology products aim to fix.

    Small Torches, Small Studios, and Small Budgets

    With small torches, studios and budgets, there are not a whole lot of available options for the lampworker – but you’re in a much better position than a lampworker with a large torch, or studio and a small budget. You can melt boro and soft glass with just a concentrator if you operate a torch that consumes a small volume of O2 per minute.

    If you’re running a small torch (more on that below) you can often build a working oxygen system around one or two oxygen concentrators. Concentrators usually come in 5, and 10 liter per minute models. Often times, jewelers and bead makers are able to use a single 5 or 10 LPM machine to run their torch. Just make sure to leave the oxygen valve on your torch cracked to provide an outlet for the oxygen concentrator, ensuring O2 purity stays high.

    Adjustable pressure relief vent 0-20 PSI for simple O2 setups.

    You can skip leaving your O2 valve open if you have our Adjustable Pressure Relief Vent installed between your concentrator and torch.

    Concentrators are usually configured to output a pressure of 4-10psi, depending on the make and model. Some specialty machines, like our Stage 1 – 10 LPM Oxygen Concentrator are capable of output pressures of up to 20psi.

    We’ll delve into why higher pressure and flow translate into more control behind the torch later on in this article.

    Torches and Flow Rates

    Selecting the right concentrator can be tricky, and not all concentrators produce the same amount or pressure of oxygen. A good starting point is our chart of torch specifications available here:

    Lampworking Torch O2 and Fuel Data

    Once you know your torch O2 consumption and it’s upper limits, you can begin to select the components of your O2 generation system.

    Why Run Higher Pressures?

    Simply put, higher pressure means higher fidelity of flame control. When we put higher pressures, and in turn higher flow rates behind a valve it increases the range of pressures and flows available to the torch.

    Increasing flow and pressure will make the needle valve knobs of a torch feel much more sensitive, and what would have previously taken several turns of the knob will now be a fraction of a turn. Think of it like going from a sluggish old beater, to driving a speedy and responsive sports car – reaction and performance are hardly comparable. Pedal to the medal actually gets you somewhere when you have the performance to match.

    How to boost the pressure of an Oxygen Concentrator – Zero Cost Option

    Most concentrators have an internal regulator that is turned down to a pressure that makes the device safe for use in a therapeutic or medical setting. We aren’t using these machines with that intent, and so boosting output pressure to more than double for no additional expense (besides labour) is a great idea for lampworkers.

    To do this, you will need to open the case of the device to gain access to the internal regulator.

    On the Stage 1, this is done by removing four Phillips head screws from the bottom of the machine and lifting off the plastic shell. Once inside, you’ll find the devices accumulator and the attached regulator.

    Regulator to boost pressure of Concentrator
    Stage 1 Oxygen Concentrator Internal Regulator can be adjusted with 6mm Hex wrench. 0-20 PSI

    Insert a 6mm hex wrench into the set screw in the bottom of the devices regulator and turn the screw clockwise, sending it inwards. Turning this screw all the way in will bring the outlet pressure of the concentrator up to 18-20 psi.

    This simple fix is often enough to meet the demands of a small torch setup. If you’re looking for more, we have two more low-cost O2 system improvements before we get into fully managed intelligent Oxygen Systems.

    Simple Tricks to Add Ease to Your Torch Workflow

    As we mentioned earlier in this article, adding an adjustable vent to your oxygen delivery system can simplify your experience behind the torch. Allowing you to fully close the valves of your torch, the adjustable vent will allow your system to accumulate O2 and some pressure before allowing excess to bleed off to atmosphere.

    By pairing a vent assembly and a small holding tank, users of a small torch can benefit from boosted and stabilized supply of O2 at their torch.

    Still not enough Oxygen?

    The next logical step is to increase the storage capacity for your low-pressure accumulation system. More storage is equal to a larger headstart in the race against a dwindling supply when a torch draws more O2 per minute is being produced.

    If increasing storage and pressure to 20 psi still aren’t enough, that is where high flow systems like the Stage 2 Compression System come into studio design.

    Compressors – High Flow or High Pressure?

    The natural answer to the limitations presented by an oxygen concentrator is a second stage of compression.

    There are a few options when it comes to compressing oxygen; and not just any air compressor will do. We require oil-free air compressors to boost the pressure of the oxygen in our systems.

    Many folks choose to DIY their systems, with plans and parts available in online groups, youtube videos and blog posts.

    Others use low flow rate, high pressure systems made for the medical industry called homefills. Both can work, but there is a superior system available for lampworkers.

    Stage 2 Compression Controller and Oxygen Management System

    Stage 2 Systems deliver High Flow and Pressure Oxygen from Oxygen Concentrators

    Some torches can get by on 20PSI and 10 or 20 LPM, but most boro lampworkers and hot shops simply cannot generate enough heat in a moment when limited by supply figures like that.

    In a production shop, we typically see line pressures of around 100 PSI and torch delivery pressures up to 65 PSI for Oxygen. Averages at 15-35 PSI for most torches are still above the pressure range that standard oxygen concentrators can deliver.

    Our Stage 2 systems can deliver the flow rates and pressures of a high demand glass studio. With a whisper quiet compressor delivering 105 PSI line pressure, and managing up to 8.0 liters per minute of production – the Stage 2 is the simple solution to boosting oxygen flow and pressure.

    Typical Production Lampworker’s Setup, 20 LPM of O2 Production and 120 Gallons of O2 Storage.

    Most hobbyist lampworkers don’t need the production volumes made possible by our Pro model, which is why we offer the Duo and Solo models. These more affordable models deliver the same boosted pressure, without as much control or delivery capability. Simpler setups for less demanding applications.

    Get Help Designing Your Studios O2 System
  • What is The Proper Name of Oxygen and Gas Fittings for Torch Hook Up and Connections

    What is The Proper Name of Oxygen and Gas Fittings for Torch Hook Up and Connections

    While helping a commenter on Facebook’s Torch Talk Group find the correct fittings for connecting a Mad Hatter manifold to a flashback arrestor, I recognized that the cryptic names and numbers of torch connection fittings can be a bit daunting to the uninitiated.

    If you are looking for the name of the fitting to connect manifolds, plumbing, flame arrestors and other fittings to weld hoses and torches – look no further:

    CGA-022-B for Oxygen connections to torches

    CGA-023-B for Fuel connections to torches

    Understanding how CGA fittings are named isn’t just for engineers — it’s critical for anyone working with gas cylinders, regulators, or torches. The CGA system provides a standardized way to match fittings to their correct gas service, preventing dangerous cross-connections and costly downtime. In this guide, we’ll break down the CGA-023 B fitting as an example, explain what each part of the code means, and provide a practical chart of common CGA connections so you can make confident, safe selections for your equipment.

    Understanding CGA Fitting Nomenclature — Breaking Down CGA-023 B

    When working with gas cylinders, regulators, and hoses, every detail in a fitting’s label matters. Take CGA-023 B for example: here’s what each component tells you, and why it’s vital for safety and compatibility.

    1. CGA — the standard behind the name

    “CGA” stands for Compressed Gas Association, a U.S. organization that defines standard connection patterns for cylinder gases so that equipment from different manufacturers can interface safely. These connection standards (often referenced in CGA’s V-1 standard) prevent mis-mating of dissimilar gases.

    In other jurisdictions or industries, you might see alternative systems (e.g. DIN, ISO, or European cylinder standards), but in North American gas supply and welding/gas fitting practice, “CGA” is the dominant convention.

    These standards map each gas (or gas family) to a specific connection code, so you can’t accidentally connect, say, an oxygen hose to a fuel cylinder with the wrong threading or shape.

    2. 023 — interpreting the numeric code

    The number “023” designates a specific connection geometry under the CGA system. In the case of CGA-023, you are looking at the B-size, left-hand thread fuel gas fitting. More precisely:

    • The “02x” family of CGA codes generally refers to B-size connections in the CGA V-1 list, suitable within a certain pressure and application envelope.
    • The difference between 023 and 022 is critical:
       • CGA-022 is the right-hand, B-size fitting intended for oxygen service. Its threading is .5625-18 UNF, RH.
       • CGA-023, conversely, is left-hand, same B-size geometry, reserved for fuel/combustible gases, so that a fuel regulator can’t be (mistakenly) attached to an oxygen cylinder.
    • More broadly, numbers in the CGA chart map to particular gases or gas classes (oxygen, inert, fuel, toxic, etc.) and thread styles. For instance, CGA-580 is common for inert gases like nitrogen or argon under high pressure.

    So, seeing “023” immediately flags to a trained user that it’s a fuel-gas, left-hand B-size interface.

    3. B — the size class

    The trailing letter (A, B, C, D, etc.) in a CGA designation refers to the size class of the fitting — essentially a shorthand grouping of thread diameter / flow capacity categories. In practice:

    • B-size is one of the more common classes for welding or small industrial fuel and oxygen lines. Because it balances adequate flow and compact form, many regulators, hoses, and torches are built around B-size fits.
    • There are C-size, D-size, and other variants in CGA’s universe (for higher flow or special uses), but in many small shop or torch setups they are less frequently encountered — so “B” is a practical default.
    • Not every CGA code uses all size letters. Sometimes the size designation is implicit in the number (e.g. CGA-580 is by convention a B-size geometry in many implementations).
    • When checking or ordering fittings, the letter helps ensure you’re matching the regulator, hose, or cylinder side correctly — mismatches in size class (even if the gas code portion is right) can lead to leaks, pressure drop, or rejection at inspection.

    Quick Reference: Common CGA Codes

    CGA CodeGas Type / UseThread DirectionSizeTypical Application
    CGA-021Fuel gas (acetylene, propane)LH (left-hand)BFuel gas cylinders and torches
    CGA-022OxygenRH (right-hand)BOxygen regulators and torch equipment
    CGA-023Fuel gas (acetylene, LPG)LH (left-hand)BFuel regulator connection (B-size)
    CGA-320Carbon Dioxide (high pressure)RHVariousBeverage CO₂ systems
    CGA-540Oxygen (high pressure)RH—Industrial oxygen cylinders
    CGA-580Inert gases (N₂, Ar, He)RH—Shielding gases, nitrogen service
    CGA-346Compressed airRH—Shop air, breathing air systems

    Tip: Left-hand threads are typically identified by a notched hex nut or grooved fitting. If the fitting won’t start by hand, don’t force it — double-check the CGA code.

    Why These Codes Matter in Practice

    Choosing fittings by CGA code isn’t just about matching threads — it’s about ensuring gas service compatibility, safety, and compliance. A CGA-023 B fitting is intentionally incompatible with CGA-022 to prevent a potentially dangerous oxygen-fuel mix-up.

    When ordering, always confirm:

    • CGA number (gas/service)
    • Thread direction (LH vs RH)
    • Size class (B, C, etc.)

    This ensures that regulators, hoses, and cylinders work as a matched system, reducing the chance of leaks or catastrophic failure.

    Still have questions? Our expert system designers are happy to guide you:

    Contact Us

  • Choosing the Right Oxygen Purity Meter for PSA Systems in Torch Work: Why We Built a Self-Calibrating Ultrasonic Option

    Choosing the Right Oxygen Purity Meter for PSA Systems in Torch Work: Why We Built a Self-Calibrating Ultrasonic Option

    If you use a PSA oxygen system for glass, metal, or flame work, you’ve probably wondered how to verify the purity coming off your concentrators and into storage. We’re introducing a lower-cost, self-calibrating oxygen purity meter that uses an ultrasonic module (speed-of-sound) rather than the typical electrochemical, paramagnetic, or zirconia techniques. This post explains the differences, where the cost savings come from, and why the accuracy trade-offs are a non-issue for PSA oxygen used in torch work.

    TL;DR: For Stage 2 compression + storage systems and similar PSA setups producing ~93–96% O2, an ultrasonic purity meter provides stable, maintenance-light readings without consumable cells—ideal for monitoring trends, diagnosing setup issues, and confirming system performance. If you’re chasing 99.9% O2 for spectroscopy or laser cutting, that’s a different toolbox; for flame work, ultrasonic is the practical win.

    First, context: What “purity” really means with PSA oxygen

    Single-stage PSA oxygen generation delivers a practical ceiling in the mid-90s (% O2) because argon rides through the sieve beds with oxygen. That’s normal—and perfectly suitable for flame work. If you’re new to PSA purity, start here:

    The common ways to measure oxygen purity (and their trade-offs)

    TechnologyHow it worksProsConsTypical fit
    Electrochemical (galvanic cell)O2 reacts at a cathode/anode and generates current proportional to O2 partial pressure.Low upfront cost; familiar; decent accuracy in the PSA range.It’s a consumable—lifespan shortens with higher O2/temperature; periodic replacement & calibration required.Portable analyzers; medical devices; general monitoring.
    ParamagneticMeasures how oxygen (paramagnetic) is attracted in a magnetic field.Non-depleting; fast response; high accuracy and stability.Higher cost; needs good flow/sample handling; more complex packaging.Process control; lab-grade monitoring.
    Zirconia (ZrO2)Heated ceramic cell measures O2 partial-pressure via ion conduction.Wide range; robust in hot/exhaust environments.Requires heaters (>300 °C); power draw; pricier probes; warm-up time.Combustion control, furnaces, engines.
    Ultrasonic (our approach)Infers composition from the gas’ speed of sound between transducers; compensates for temperature/pressure/humidity.Solid-state; no consumables; quick warm-up; inherently stable; lends itself to self-calibration against ambient air.Requires good compensation for humidity/temperature and steady flow; absolute accuracy depends on calibration method.PSA systems, trend monitoring, long-term shop use.

    Why we chose ultrasonic for PSA oxygen in torch work

    1. No consumables to replace. Electrochemical cells age and need periodic swap-outs. Our ultrasonic module is solid-state, so ongoing costs are lower—one of the key reasons we can price this device more affordably.
    2. Self-calibration against ambient air. Before use, the meter can reference outdoor/room air (≈20.9% O2) to confirm scale and temperature compensation—no bottled calibration gas required.
    3. Accuracy that matches the application. In a PSA band of ~93–96% O2, what matters most for a torch is consistency and diagnostics, not chasing 99.9%. Small percentage-point swings won’t change how your flame behaves on common torches. (Cross-check with our Lampworking Torch Data and model selection on the Oxygen Runtime Calculator.)
    4. Lower system complexity. Paramagnetic and zirconia analyzers are excellent but add cost and integration overhead that doesn’t translate into practical benefits at the bench for PSA users.

    Where ultrasonic shines in the studio

    • Commissioning: Verify that your Stage 1 concentrators and Stage 2 purity controls (e.g., Pre-Vent) are doing their job before storing gas.
    • Trend monitoring: Watch purity over time to catch clogged filters, tired sieve beds, or incorrect valve timing early.
    • Troubleshooting: If your flame feels “off,” a quick purity check alongside runtime/pressure data helps isolate the issue.

    Accuracy & limitations (straight talk)

    Any oxygen analyzer is only as good as its sampling and compensation. Our ultrasonic meter measures temperature and uses humidity/flow best-practices to keep readings stable in the PSA range. For industrial torch work, you want repeatable numbers and alarms around thresholds—not lab-grade metrology. If you do need more stringent verification, we’re happy to recommend workflows that pair our ultrasonic meter with a periodic cross-check device.

    Cost-of-ownership: why this meter is more affordable

    • No sensor cartridges to replace (unlike galvanic cells).
    • No heaters or magnetic assemblies to drive (unlike zirconia or paramagnetic analyzers).
    • Shop-ready packaging designed for the realities of flame work, not clean-room lab benches.

    If you’re running delivered cylinders or LOX and considering PSA, take a look at the math: Stage 2 ROI breakdown and How much is your oxygen costing you?

    What “good” looks like on PSA

    Healthy PSA setups consistently store oxygen above 95% (with argon making up most of the balance). Our Stage 2 Features like adjustable Pre-Vent are designed to vent initial impurities so you only store the good stuff. If you’re sizing or upgrading, compare SOLO, DUO, and PRO, or read our overview of oxygen systems.

    Related reading on DPG

    Availability & next steps

    Our ultrasonic oxygen purity meter is designed for industrial use only (not medical) and pairs perfectly with the Stage 2 compression platform. Want early access or to discuss your setup? Contact an oxygen system specialist.

  • Ultrasonic Technology Makes Oxygen Purity Measurement More Affordable for Torch Workers

    Ultrasonic Technology Makes Oxygen Purity Measurement More Affordable for Torch Workers

    Introducing: The O2 Flamedex! View oxygen purity and resulting maximum flame temperatures in Celcius and Farenheit. Runs on 3xAA batteries.

    When it comes to oxy-fuel cutting and welding, oxygen purity isn’t just a number — it’s the backbone of consistent performance. If oxygen purity dips, flame temperature drops, cut quality suffers, and operations become less efficient. Traditionally, ensuring that purity meant relying on expensive and maintenance-heavy analyzers. That’s about to change.

    DPG Supply is proud to introduce a new, lower-cost oxygen purity meter built on self-calibrating ultrasonic technology. This innovative approach provides reliable readings for PSA oxygen purity monitoring used in torch applications — without the complexity or cost of legacy analyzers.

    Understanding Oxygen Purity Measurement Technologies

    Before diving into why ultrasonic is a game-changer, it helps to understand the conventional technologies used to measure oxygen purity and why they can be expensive to own and operate.

    1. Electrochemical / Galvanic Sensors

    Electrochemical sensors, often found in medical and industrial oxygen analyzers, use a chemical cell to generate a current proportional to oxygen concentration. While relatively affordable, these sensors have a limited lifespan — they consume their internal electrolyte over time and require regular calibration and replacement.

    • ✅ Low initial cost
    • ❌ Drifts over time and needs recalibration
    • ❌ Temperature and humidity sensitivity
    • ❌ Consumable sensor elements increase lifetime cost

    2. Zirconia (Solid-State) Sensors

    Zirconia cells measure oxygen concentration using a heated ceramic element. These analyzers are fast and reliable in high-demand industrial settings, but the heater, precision control electronics, and calibration routines make them costly and more complex.

    • ✅ High temperature stability and fast response
    • ❌ Expensive materials and build
    • ❌ Requires stable reference gas and periodic calibration
    • ❌ Best suited for gas plants or lab environments

    3. Paramagnetic & Lab-Grade Analyzers

    Paramagnetic analyzers detect oxygen’s magnetic susceptibility and provide high precision but come with high upfront costs, sensitive components, and the need for expert maintenance. Even more complex are mass spectrometry or gas chromatography systems — incredibly accurate, but completely impractical for day-to-day torch work.

    • ✅ Excellent accuracy and fast response
    • ❌ High cost and complexity
    • ❌ Requires controlled environments
    • ❌ Overkill for PSA oxygen applications

    Why Ultrasonic Modules Are Changing the Game

    Unlike the technologies above, ultrasonic oxygen purity meters work by measuring the speed of sound through the gas. Because oxygen and nitrogen have different acoustic properties, the device can accurately determine the oxygen concentration by analyzing transit time.

    Our new ultrasonic oxygen purity meter takes advantage of this principle — but with a modern twist: it self-calibrates, minimizing drift and eliminating the need for expensive sensor replacements.

    Key Benefits of Ultrasonic Measurement

    • No consumables: Nothing to replace or degrade over time.
    • Self-calibrating: Maintains accuracy with minimal user intervention.
    • Lower cost: Simpler components mean more affordable pricing.
    • Low maintenance: Ideal for shop or field use.
    • Durable: Resistant to moisture and vibration, making it perfect for PSA systems.

    In PSA torch applications, where oxygen purity typically falls between 90 % and 96 %, this level of precision is more than sufficient to ensure consistent cutting and welding performance in glass — at a fraction of the price of zirconia or paramagnetic analyzers.

    Accuracy Where It Counts

    One common misconception is that lower cost means lower performance. In fact, for most torch work applications, ultra-high precision (±0.1 %) isn’t necessary. A device that can reliably differentiate between, say, 60 %, 75 %, and 95 % purity will deliver actionable insights and ensure optimal torch performance.

    • PSA systems already have a known operating purity range.
    • Oxy-fuel heating has a generous tolerance window.

    Even if the absolute accuracy is ±3 %, your readings remain fully fit for purpose. And because the unit self-calibrates, drift is minimized — no electrode wear, no recalibration gases, no consumable parts.

    Lower Cost, Longer Life

    Traditional oxygen analyzers can require sensor replacements every 12–24 months and frequent recalibration. Our ultrasonic oxygen purity meter is designed for years of operation without consumable parts, which means:

    • ✅ Lower total cost of ownership
    • ✅ Less downtime
    • ✅ Less user training required

    This makes it an ideal fit for small shops, field service providers, and mobile oxygen systems — anyone who needs reliable purity measurement without breaking the bank.

    Visit our Products page to see the full line of gas analysis solutions.

    Designed for PSA Oxygen and Torch Work

    Our ultrasonic purity meter isn’t trying to compete with laboratory-grade analyzers. Instead, it’s optimized for the PSA oxygen systems commonly used in cutting, brazing, and welding. In these environments, what matters most is:

    • ✔ Consistent readings in the 90–96 % range
    • ✔ Minimal maintenance
    • ✔ Simple operation

    And that’s exactly what our self-calibrating ultrasonic module delivers.

    Get Early Access

    We’re excited to bring this new technology to the field. If you want to reduce costs, simplify operations, and get reliable purity measurement for your PSA oxygen system, our ultrasonic oxygen purity meter is the perfect fit.

    Contact us today to reserve your unit or learn more about our upcoming release.

    Learn more about PSA oxygen systems and how they integrate with torch setups.

  • How Pure Can Concentrated Oxygen Get? The Real Limit — and Why PSA Works for Glassblowers

    How Pure Can Concentrated Oxygen Get? The Real Limit — and Why PSA Works for Glassblowers

    Concentrators make enriched oxygen using PSA technology. There’s a natural question: How pure can PSA/Concentrated Oxygen actually get, and does that matter at the bench?

    For glassblowers, oxygen quality shows up in the flame: heat, stability, and how predictably the torch responds when you push your work. Given this importance, why would studios move away from cylinders of 99.9% oxygen to on-site systems built around pressure swing adsorption (PSA or Concentrated Oxygen)?

    The Practical Ceiling for PSA Purity is 96.3%

    In real-world operation, PSA oxygen generators are designed and specified for about 93–96% O₂. That’s not a marketing number—it’s the accepted performance band you’ll see across technical guidance and medical oxygen programs that use PSA plants.

    Why that band? Pushing beyond the mid-90s with PSA quickly forces expensive trade-offs between purity, flow, and stability. Raise purity a couple of points and your available flow typically drops—meaning a larger (costlier) oxygen concentrator system to get the same output.

    Why Concentrators (PSA) Can’t Hit 100%: The Argon Problem

    PSA beds (zeolites – the stuff inside of oxygen concentrators doing the magic) are excellent at holding back nitrogen while letting oxygen pass. But argon—about 0.9% of ambient air—behaves a lot like oxygen in this process and tends to slip through with it. That’s why most PSA streams top out in the mid-90s: you’ve removed the nitrogen efficiently, but a small fraction of argon remains.

    What that means at the torch

    For artistic and functional glasswork, 93–96% PSA oxygen is more than hot enough for stable, repeatable flames on common torches. In practice, the bigger wins for glassblowers come from supply consistency and economics: no delivery gaps, no cylinder swaps mid-project, and a predictable cost per hour.

    If you’re considering the switch, start by looking at system architecture and how it fits your studio:

    PSA vs. “near-pure” alternatives

    Could you chase 99.5%+? Yes—cryogenic oxygen or multi-stage PSA hybrids can get there, but they come with plant-scale cost, more complex controls, and longer startup dynamics. That’s why PSA is often called the most cost-effective way to get close to pure oxygen at useful volumes without plant-sized equipment. For most glass studios, the mid-90s purity band delivers the best combination of flame performance, uptime, and total cost of ownership.

    Sizing your setup for real studio workloads

    Two practical steps help you right-size a PSA-based system:

    1. Quantify your run time and peak draws with the Oxygen Runtime Calculator.
    2. Cross-check burner requirements using the Lampworking Torch Data.

    Once you have a rough profile, match it to a compression model and storage strategy:

    For specifics on noise, warranty, or common fit questions, see the FAQ and Warranty.

    Why this approach scales with you as a professional artist

    Your demand may grow—from solo bench time to multi-artist production. PSA is modular by design: add concentrators, expand storage, and let the compression stage handle the duty cycle. That’s the path most studios take to eliminate refill logistics while keeping flame behavior consistent day to day. For a quick orientation to the company and user community, see About Us and Our Artists.

    Bottom line

    • Maximum practical PSA purity: about 93–96% O₂.
    • Reason: argon behaves like oxygen in standard PSA beds, creating a hard limit without costly extra stages.
    • Best fit for glassblowers: on-site PSA provides stable, hot flames with far better economics and uptime than cylinder delivery for most studios.

    If you want help mapping purity, flow, and storage to your torch lineup, we can put numbers to it and recommend a build. Start here:

    Contact an Oxygen System Expert

    Sources for the purity limit and trade-offs

    • WHO / technical guidance on PSA output: oxygen 93% ± 3% and performance considerations. Iris+1
    • Argon carry-through in PSA and practical purity ceilings near ~95%. nzic.org.nz+1

  • Scaling Challenges and Sustainable Solutions in Stage 2 ETL Certification

    Scaling Challenges and Sustainable Solutions in Stage 2 ETL Certification

    As we continue refining our machines and processes, the recent ETL inspection of our Stage 2 unit reminded us of two important truths: scaling up comes with greater complexity, and every challenge is an opportunity to reaffirm our commitment to sustainability.

    Scaling Up Means Scaling the Risks

    When production moves from single units to batch manufacturing, the stakes rise accordingly. A minor adjustment at a small scale can become a significant disruption when applied across multiple machines.

    During our inspection, it became necessary to relocate two grounds within the Stage 2 machine. While the task itself was straightforward, the implications were not. To accommodate the changes, every power cord needed to be shortened and re-terminated. Across five machines, that meant 45 individual wires with crimped connectors had to be reworked. What could have been a simple adjustment in a prototype environment became a complex, time-consuming process at production scale.

    This experience highlights a reality that any manufacturing team faces: scaling magnifies both the risks and the remedies. What matters is how you handle those challenges.

    Commitment to Low-Waste Solutions

    For us, the answer lies in smart design and sustainable thinking. Although the rework created 45 shortened wires with connectors already attached, none of that material will go to waste. That’s not by chance—it’s by design.

    From the start, we’ve standardized our machines to use common connector types throughout. This means that the wires and connectors we removed can be reused seamlessly in other areas of future units. Instead of becoming scrap, every piece will find a new purpose.

    Different Types of Quick-Connect Spade Receptacles Used in a Stage 2

    By taking this approach, we not only reduce waste but also reaffirm our broader commitment to an eco-friendly, low-waste manufacturing process. The lesson here is simple: thoughtful design doesn’t just improve performance—it ensures sustainability is built into every step.

    Looking Ahead

    This ETL inspection tested our ability to adapt under pressure, but it also reinforced the values that guide our work. Scaling production will always introduce challenges, but by combining technical rigor with sustainable design, we’re proving that setbacks can be turned into opportunities for innovation and responsibility.

    Click here to browse the Stage 2 models.

  • Understanding Studio Ventilation: A Practical Primer for Glassworkers

    Whether you’re new to torchwork or optimizing an existing studio, proper ventilation isn’t just a comfort issue—it’s critical to your health and safety. In a field where fumes, heat, and combustion byproducts are common, understanding how to design an effective ventilation system is non-negotiable.

    For years, Mike Aurelius’ Ventilation Primer has been recognized as a go-to reference in the art glass community—a foundational resource for anyone working with torch-based processes. This long-standing series, authored by a respected expert in lampworking safety, offers clear, actionable guidance on everything from airflow calculations to effective studio layout. Below, we highlight some of the core concepts—but for the complete technical deep dive, we encourage readers to consult the original Ventilation Primer.

    Why Ventilation Matters

    In torch-based work, harmful gases like nitrogen dioxide (NO₂) can build up quickly. Without effective airflow, these substances linger in your breathing zone, posing serious long-term health risks. A well-designed ventilation system removes fumes at the source and replaces them with clean air—protecting both you and your studio environment.

    The Core Concepts

    Mike Aurelius’s primer introduces several vital engineering principles, adapted for practical studio use:

    1. Airflow and Velocity

    To move toxic fumes efficiently, you need to create directional airflow at a specific speed—typically measured in feet per minute (FPM) and cubic feet per minute (CFM). Aurelius provides clear formulas:

    • CFM = Hood Area × Velocity × Efficiency Factor
    • Velocity Pressure (VP) = (Velocity ÷ 4004)²

    Understanding these values helps ensure your system has enough pull to capture the full fume plume from your torch.

    2. Sizing Your Ducting and Fan

    Duct diameter, length, and bends all affect resistance in your system. The primer offers step-by-step guidance for calculating static pressure losses—critical for choosing a properly rated fan that won’t underperform once installed.

    3. The Trouble with Overhead Hoods

    Many glassworkers use standard box-style hoods mounted overhead—but Aurelius explains why this setup often fails. Most suction happens directly at the duct opening, so if your hood is too large or the duct is too far from the source, fumes escape into the room. Alternatives like rear-wall or bench-level capture are more efficient for torchwork.

    Environmental Adjustments

    Operating at high altitude or in extreme temperatures? You’ll need to account for changes in air density. The series shows how to modify calculations for realistic pressure and airflow conditions, which can dramatically affect your system’s performance.

    Other Smart Design Tips

    • Make-up Air: Always ensure your ventilation system is pulling in fresh air to replace what’s being exhausted—especially if you work in a tightly sealed space.
    • Noise Management: Aurelius discusses techniques to reduce fan noise without sacrificing effectiveness, including fan placement and vibration isolation.
    • Cold Weather Strategies: In frigid climates, options like under-bench ducting help reduce drafts and keep workspaces comfortable.

    Final Thoughts

    Setting up effective ventilation doesn’t require an engineering degree, but it does demand some careful planning. This guide provides the foundation—calculations, design considerations, and troubleshooting—but the best results come from tailoring your setup to your specific space and work style.

    For full technical details, calculations, and diagrams, read Mike Aurelius’ complete Ventilation Primer. It’s one of the most comprehensive resources available for glassworkers and studio safety enthusiasts alike.

  • Designing for Durability: Why PTC Fittings and TPU Tubing Outperform Under Pressure

    Designing for Durability: Why PTC Fittings and TPU Tubing Outperform Under Pressure

    Oxygen compression systems demand reliability. Heat, vibration, and continuous operation can quickly expose the weaknesses of traditional hose clamps or barbed fittings. The result? Leaks, inefficiencies, and safety risks.

    A better solution is pairing TPU (Thermoplastic Polyurethane) tubing with Push-to-Connect (PTC) fittings. This combination delivers strength, stability, and ease of use. Exactly what oxygen systems need.

    Secure Under Stress

    Unlike rigid materials that can loosen or crack, TPU is flexible yet durable, absorbing vibration without losing form. Paired with PTC fittings—which lock the tubing in place with precision seals—connections remain tight and reliable. Even in high-vibration environments, this setup resists leaks and fitting fatigue.

    TPU Tubes 1/4″

    Built for Heat

    Continuous operation means elevated temperatures, and TPU handles heat far better than PVC. It maintains elasticity up to around 80°C, while quality PTC fittings are rated for similar or higher ranges. Together, they provide consistent performance where other tubing-fittings systems often fail.

    Clean, Leak-Free Operation

    PTC fittings use internal O-rings that seal firmly against TPU’s surface. This eliminates oxygen loss, protects system efficiency, and ensures safety. For oxygen-rich environments, clean, leak-free connections are non-negotiable—and this pairing delivers.

    Fast, Simple, Reliable

    No clamps, no tools, no complicated setup. PTC fittings connect in seconds and release just as easily for maintenance. TPU tubing complements this with flexibility and durability, making the system not only reliable but also efficient to service.

    The Bottom Line

    For oxygen systems under constant demand, PTC fittings and TPU tubing offer the perfect balance of:

    • Long-term durability
    • Leak-resistant performance
    • Heat and vibration resilience
    • Quick, tool-free installation
    • Oxygen-safe materials

    Whether your setup is stationary or mobile, this combination provides dependable performance with minimal maintenance—so your system stays focused on what it was built to do.

    Need help selecting the right PTC fittings and TPU tubing for your system? Our team offers expert guidance and a full range of compatible components to meet your application’s needs.

    Contact us here!

  • Introduction to Oxygen Generation Systems and PSA Technology

    Introduction to Oxygen Generation Systems and PSA Technology

    In a wide range of industries—from healthcare to manufacturing—oxygen is a critical resource. While bottled or liquefied oxygen has traditionally been supplied through delivery and storage systems, on-site oxygen generation is increasingly becoming the go-to solution for businesses and facilities seeking a more reliable, cost-effective, and scalable oxygen supply. One of the most popular technologies enabling this transition is Pressure Swing Adsorption, or PSA.

    What Is an Oxygen Generation System?

    An oxygen generation system is a device or setup designed to extract oxygen from ambient air and concentrate it for use in various applications. Ambient air contains about 78% nitrogen, 21% oxygen, and small amounts of other gases. Oxygen generation systems separate these components to provide a high-purity oxygen stream, typically in the 90–95% range, depending on the design and application requirements.

    How PSA (Pressure Swing Adsorption) Works

    Pressure Swing Adsorption (PSA) is the most common method used in modern oxygen generators. This technology leverages the principles of adsorption—a physical process where gas molecules adhere to the surface of a solid material.

    Stage 1 – 10LPM Oxygen Concentrator

    Step-by-Step Process:

    1. Air Compression and Conditioning: Ambient air is drawn into the system, compressed, and filtered to remove dust, moisture, and oil vapors.
    2. Nitrogen Adsorption: The purified air is passed through a vessel containing a material called zeolite, which preferentially adsorbs nitrogen under pressure while allowing oxygen to pass through.
    3. Oxygen Collection: The oxygen-rich gas exits the adsorption vessel and is collected in a storage tank or routed directly to the point of use.
    4. Desorption and Regeneration: The zeolite bed becomes saturated with nitrogen and must be regenerated. This is done by reducing pressure in the vessel, which releases the trapped nitrogen and vents it out. While one vessel is in the adsorption phase, the other is in regeneration—hence the “swing” in PSA.
    5. Continuous Cycle: The process alternates between the two vessels in a timed cycle, ensuring a constant supply of oxygen.

    Applications of PSA Oxygen Generation Systems

    Oxygen generated through PSA systems is used in a diverse array of industries:

    1. Glass and Ceramics

    Oxygen enhances combustion efficiency in furnaces, reducing fuel consumption and emissions.

    2. Water Treatment

    Oxygen is used to enhance biological treatment in wastewater plants and for ozone generation in advanced oxidation processes.

    3. Metal Processing and Welding

    Oxygen supports combustion in high-temperature applications like cutting, brazing, and welding metals.

    4. Aquaculture

    Oxygen-enriched water improves fish health and growth rates in commercial aquaculture operations.

    5. Food and Beverage

    It plays a role in packaging and fermentation processes, ensuring freshness and safety.

    Introducing the Stage 2 Oxygen Control and Compression System

    At DPG, we are proud to offer the Stage 2, our next-generation oxygen control and compression system designed to meet the highest standards of efficiency, durability, and purity.

    Stage 2 on DPG Assembly Bench

    Key Features of a Stage 2 System:

    • High Oxygen Purity: When paired with our Stage 1 Oxygen Concentrators, it will deliver up to 96% pure oxygen with stable performance.
    • Modular Design: Scalable to meet the demands of small studios or large industrial setups.
    • Low Maintenance: Built with premium components for extended service life and minimal downtime.
    • Energy-Efficient: Optimized for reduced power consumption without compromising output.

    Whether you’re a manufacturer aiming to boost productivity and sustainability or an artist looking to decrease overhead and hassle, the Stage 2 offers a future-ready oxygen solution tailored to your needs.

    Final Thoughts

    PSA oxygen generation systems represent a transformative shift in how industries access and manage oxygen. They offer autonomy, efficiency, and reliability that traditional supply chains simply can’t match. With the Stage 2, you’re not just investing in an oxygen generation system—you’re investing in resilience, performance, and peace of mind.

    Shop Oxygen Systems