Weld All Around Symbol: AWS & ISO Meaning, Placement, and Best Practices

Table of Contents

What Is the Weld All Around Symbol? A Complete Introduction

You’re standing at the layout table with a fabrication drawing for a mounting bracket, coffee in hand, tracing the joint with your finger. The callout looks straightforward: a fillet weld with a 6 mm leg, sitting below the reference line, meaning it goes on the arrow side. Then you spot it — a small circle tucked right where the arrow line bends into the reference line. It reads like a drafting smudge, easy to ignore. It is not a smudge. That circle is the weld all around symbol, and it just expanded the scope of your entire job.

In the language of welding drawings, the weld all around symbol is a supplementary symbol — a small circle placed at the junction, or bend, where the arrow line meets the reference line of a welding symbol. Its meaning is precise: the specified weld must be applied continuously around the entire perimeter of the joint rather than at a single location. Where a standard symbol answers the question “which side?”, the all around symbol answers it with “every side.” It’s one of the few markings that changes the geometry of the weld, not just its size or position. And unlike a weld size that can be argued in the field, this circle is binary: either the joint is welded all the way around, or it isn’t. The official AWS weld symbol chart shows every supplementary symbol at a glance, including this one.

That distinction matters more than most welders realize. In the conventional welding-symbol system, information below the reference line applies to the arrow side of the joint, and information above it applies to the other side. The all around circle doesn’t sit above or below the line — it sits exactly on the bend, deliberately outside that logic. When you see it, forget about arrow side versus other side entirely. The weld wraps 360 degrees around the part, whether that’s the full circumference of a pipe, the rectangular face of a tube fitting, or the closed loop of a gusset plate.

The system you’re reading is older than most of the people using it. The AWS A2.4 welding-symbol system originated in 1976, when it combined and superseded two earlier standards: AWS A2.0, first published in 1947, and AWS A2.2, first published in 1958. The current edition, AWS A2.4:2020, is the eighth edition, approved by ANSI on January 9, 2020, and superseding AWS A2.4:2012. The international counterpart, ISO 2553, covers the same territory with some important drawing differences — a topic worth its own deep dive. The symbol’s longevity is a testament to how well the system works: it has survived nearly five decades of process innovation, from stick and TIG to robotic submerged arc welding.

Misreading this symbol is expensive. Welders who treat it as an arrow-side callout under-weld the joint, leaving sections of the perimeter unwelded. That shows up as rework, failed inspections, and — in structural work — joints that carry nowhere near their rated strength. Under-welding also invites defects like overlap and lack of fusion at the start-stop points where the weld wraps around corners. The fix is cheap: learn what the circle means and check for it on every print you touch. If you’re still building your print-reading instincts, a structured welding practice routine is where that habit starts.

This guide walks through the full picture: how the symbol is drawn under AWS A2.4 and ISO 2553, where you’ll actually encounter all around welds in the shop, the compliance and quality mistakes that cause costly rework, how inspectors verify these welds with NDT and acceptance criteria, and the best practices that keep detailers and welders on the same page — from the first read of the print to the final pass.

Quick Note: The weld all around symbol is a circle, not a weld size, not a process letter, and not a decorative flourish. It belongs at the junction of the arrow and reference lines. If you see it anywhere else on the symbol, question the drawing before you strike an arc.

Anatomy of a Welding Symbol: Where the All Around Circle Fits

Before you can trust that little circle, you need to know the machine it lives in. A welding symbol isn’t a random doodle — it’s a standardized instruction set, and every line, letter, and mark carries a job. Get the anatomy right and the all-around circle stops being mysterious and starts being obvious.

The backbone is the reference line, a horizontal line that holds the weld details. Above it sit instructions for the “other side”; below it sit instructions for the “arrow side.” The arrow connects that reference line to the actual joint, and here’s the key convention: the side the arrow points to is the arrow side, and the opposite side is the other side. Move the weld symbol from below the line to above it, and you’ve flipped which face gets the weld.

The tail lives at the far end of the reference line and carries process or specification information — think SMAW, GTAW, FCAW, or a procedure reference. When you see “GTAW” in a tail, that’s a direct signal to dial in your setup, and the fine details of polarity matter enormously here. If you’re running a tungsten arc, our guide to TIG welding polarity breaks down exactly how DCEN, DCEP, and AC change the arc.

The Weld Symbols Themselves

Between arrow, reference line, and tail sits the weld symbol — the shape that tells you what kind of weld to make. AWS A2.4:2020 details symbols for groove, fillet, plug, slot, spot, seam, edge, stud, and surfacing welds, plus brazing and nondestructive examination symbols. Each one has a home on the reference line, and each can be modified.

Dimensions travel with those symbols: size (leg length, groove depth), length, and pitch (spacing for intermittent welds). Supplementary symbols layer on top — contour and finish marks, melt-thru, field weld, and of course the all-around circle.

Reading a Symbol Top to Bottom, Left to Right

Train your eye in a repeatable order so nothing slips past you:

Arrow first — find the joint and which side is the arrow side.
Reference line — read left to right, noting position above or below.
Weld symbol and dimensions — what weld, how big, how long.
Supplementary symbols — contour, field weld, all-around.
Tail — process and specification.

ISO 2553 does things a little differently. It uses a dual-reference-line system with a dashed line to indicate welds on the far side of a plate — a subtle difference that trips up anyone bouncing between AWS and ISO drawings. You can compare the two approaches at the ISO 2553 standard page.

Why the All Around Circle Is Different

Here’s the crucial distinction. Every other symbol on the reference line answers “which side?” The all-around circle does not. It’s a modifier that rides along with whatever weld symbol it accompanies — fillet, groove, or otherwise — and it overrides the side question entirely. It says: weld this joint continuously around the entire perimeter, arrow side and other side alike.

Quick Note: The circle sits exactly where the arrow meets the reference line. That spot is the universal “modifier junction,” which is why it’s so easy to overlook on a busy drawing.

Think of it as a multiplier, not a location. A fillet symbol tells you the weld type and size; the circle tells you it doesn’t stop. That’s why experienced fabricators read the circle before they read the dimensions — it changes the scope of the whole job. For anyone building real skill in decoding drawings and executing them, our complete guide to welding practice is worth keeping close, and understanding filler and consumable behavior — like the composition covered in MIG welding wire — reinforces why continuous perimeter welds demand consistent technique.

What the All Around Symbol Actually Means: 360-Degree Continuous Welding

Strip away the drafting conventions and the all around symbol says something refreshingly simple: keep welding until you arrive back where you started. The specified weld travels continuously around the entire perimeter of the joint — a full 360-degree circumferential weld on a pipe or tube, a bead wrapping all four sides of a box section, or a pass circling a boss until it closes on itself. That tiny circle where the arrow meets the reference line is really a scope instruction: the joint is a loop, not a line.

Continuous Around the Perimeter — Not Segments

Picture a pipe butted to a flange. Without the circle, an arrow touching the joint could imply a weld only at that spot. With it, the weld runs the full circumference in one continuous sequence. No gaps, no skipped stretches, no stopping points. Here is where people confuse themselves. The all around symbol is not the same as welding both sides of a joint; a double-sided weld can still be partial, and it is drawn with a weld symbol on each side of the reference line. Nor is it an intermittent weld, which deliberately leaves unwelded spans. An all-around weld is one unbroken ring.

What Happens to Length and Pitch Dimensions

Length and pitch numbers belong to intermittent welds: a note like 2-6 means a two-inch weld every six inches. An all-around weld has no pitch because there is nowhere to skip. When a drawing pairs the all around circle with a length dimension, treat the continuous loop as the governing requirement; the perimeter is welded in full and the pitch concept simply does not apply. If a designer genuinely wants an intermittent weld, the all around circle should not be there at all. Mixing the two on one symbol creates ambiguity that ends up as a question in the shop — or worse, as rework.

Quick Note: Per ISO 2553 guidance, the weld-all-around symbol indicates a complete arc around a joint and should not be used where multiple types of weld are required. It is also distinct from the field weld symbol (the flag), which only tells you where the weld is made — the shop or the site.

One Continuous Pass — or Several, But Never a Segment

An all-around weld is often deposited as a single continuous pass, but that is not a rule. On thicker material it may take a root pass, fill passes, and a cap, or several beads side by side, all chasing each other around the loop. What matters is that the finished weld is continuous. This is the key difference from a segment weld, which covers part of the perimeter by design. A segment weld has defined start and stop points; an all-around weld’s only stop point is where it began. On pipe, welders often stagger their start/stop location from pass to pass to avoid stacking defects in one weak spot — a habit that pays off under inspection.

Does All Around Mean Full Penetration?

No — and this is one of the most expensive assumptions in fabrication. The circle controls where the weld goes, not how deep it bites. Penetration comes from the associated weld symbol and its dimensions, or from the governing code and the qualified welding procedure. A groove weld with a partial-joint-penetration detail can still carry the all around circle, and so can a fillet weld, which has no defined penetration beyond fusion at the root. If a joint truly needs full penetration, that requirement appears as a groove symbol, a backing detail, or a note — never as the little circle alone.

Putting the symbol to work is mostly about recognizing the loop. On tube and fitting work, that means planning your travel so the closure point lands somewhere inspectable rather than in a tight corner. On automated setups, it means programming the full rotation instead of a partial sweep; robotic submerged arc welding, for example, is built for exactly these long, uninterrupted circumferential passes. And prep always shows: a continuous weld over poor fit-up simply carries the defect all the way around, which is why solid welding practice starts long before the arc does.

AWS A2.4 vs ISO 2553: How Each Standard Draws the All Around Symbol

Two standards dominate welding drawings worldwide: AWS A2.4 in North America and ISO 2553 almost everywhere else. Both place the all-around circle at the junction of the arrow and the reference line, but the surrounding conventions diverge sharply—especially how each side of the joint is indicated. Mix them up, and a correct-looking symbol means the wrong thing.

The AWS A2.4 Approach: One Line and Arrow-Side Logic

Under AWS A2.4, whose 2020 edition is current, a welding symbol sits on a single reference line. Anything written below that line applies to the side the arrow touches (the arrow side); anything written above applies to the other side. There is no dashed line anywhere in the AWS system. The all-around circle is placed precisely where the leader’s arrow meets the reference line, and it governs the entire joint—no matter which side the arrow points toward. That economy is deliberate: one line, one position, one meaning.

ISO 2553 System A: The Dual Reference Line

What many people casually call “the ISO method” is really System A. It uses two parallel reference lines, a solid line and a dashed line. Where AWS leans on position alone, ISO System A uses the dashed line plus arrow-side convention to sort out which side gets what. ISO 2553:2019, Edition 5 published in March 2019, defines the symbolic representation of welded joints, and its clauses are suffixed “A” for this dual-line system and “B” for the single-line one.

ISO 2553 System B: The Single Reference Line

System B drops the dashed line and behaves much like AWS—one reference line, arrow-side logic. The catch is that fillet dimensioning and several other conventions still differ from A2.4, so a symbol that looks identical can carry a different meaning across the two families. Crossing them without noticing is the real risk: a System A symbol carries a dashed line that means nothing in AWS A2.4, and a welder trained only on AWS may read the solid line as the whole story.

Annex F: AWS Publishes Its Own ISO Comparison

Acknowledging the confusion, AWS A2.4:2020 includes informative Annex F, ISO 2553 Welding Symbols, which compares ISO and AWS conventions side by side. An ISO annex first appeared in AWS A2.4:2012, so the comparison is a long-standing feature, not a novelty. It confirms where the systems agree—such as the all-around circle’s location—and where they do not, notably arrow-side indication (dashed line in ISO System A versus position in AWS) and fillet dimensioning. The differences are easiest to see in a side-by-side view:

Feature	AWS A2.4	ISO 2553 System A	ISO 2553 System B
Reference line	Single	Dual (solid + dashed)	Single
Arrow-side indication	Position below/above line	Solid vs. dashed line	Position below/above line
All-around circle	At arrow/line junction	At arrow/line junction	At arrow/line junction
Fillet dimensioning	Leg size, AWS conventions	ISO conventions	ISO conventions

Quick Note: ISO/DIS 2553, a draft 6th edition, is under development and would eventually replace ISO 2553:2019. Until it is published, the 2019 edition remains the working reference.

Read the Drawing by the Standard It Names

Here is the rule that saves rework: check the drawing notes before interpreting a single symbol. A print governed by AWS A2.4 must be read per A2.4; one citing ISO 2553 must be read per ISO. The all-around circle looks the same in both, but the reference-line logic around it does not. When a project spans continents, that mismatch—say, an ISO-produced detail interpreted by an AWS-trained welder—is exactly how a 360-degree weld gets applied to the wrong side or omitted entirely.

Train detailers and welders on both families, and build structured welding practice around drawing interpretation—on par with polarity selection or joint prep. Whether the joint calls for gasless flux-cored welding or a robotic submerged arc cell, the symbol still means one continuous pass around the perimeter. Keep the standard’s name visible in the title block and WPS, and get the standard right so the weld is right.

Where You’ll See It: Real Applications for All Around Welds

Once you know what the circle means, you start spotting it everywhere. It appears on pipe spools in a refinery fab shop, on ladder rails bolted to a warehouse mezzanine, and on the stainless skid that carries a dairy pasteurizer. The logic behind all of them is the same: some joints cannot tolerate a partial weld. Choose a random start and stop point on a pressurized line and you have just created a potential leak path. Wrap the entire perimeter, and the joint becomes a single continuous seal. In other words, the symbol shows up wherever a seam has to close a loop.

Pressure Piping and Pipe Spools

Process piping is the symbol’s home turf. Spools arrive with girth welds at elbows, tees, reducers, and flanges, and most of those joints are specified all-around by default. Why? Because a pressure boundary has to hold from every direction — internal pressure, thermal expansion, vibration, and the occasional water hammer. A partial weld at a fitting is a stress riser and a leak waiting to happen. On a large spool run, each girth weld gets its own symbol, but the all-around designation appears on nearly every one, keeping the pressure boundary unbroken from flange to flange. Welders who jump between pipe and plate quickly learn that the circle changes their whole travel plan — there is no convenient stopping point. Alignment is everything here; gaps at the root will show up as lack of fusion, so before the arc even strikes it’s worth reviewing the fit-up conventions covered in our guide to weld tube fittings.

Pressure Vessels, Storage Tanks, and Encasement Pipe

Vessels, tanks, and their nozzles live under the same rule. Nozzle-to-shell connections, manway rims, and reinforcing pads all demand continuous sealing for pressure containment and corrosion resistance — an interrupted weld on a tank shell is a future rust pit. Storage tank shells, in particular, are built from rolled plate with vertical and horizontal seams that must be leak-tight for decades, so the all-around callout is less an option and more a baseline requirement. That continuous seal is what keeps product in and contaminants out. You’ll even find the symbol outside the process world. A public NCDOT materials document on encasement pipe, which uses AWS A2.4 weld symbol definitions, shows the WELD ALL AROUND symbol applied to encasement pipe, where a fully wrapped joint protects the carrier pipe from groundwater intrusion.

Tubular and Box-Section Structural Joints

Structural round tube, square tube, and box sections are another stronghold. Wrapping the joint isn’t just about sealing — it’s about stiffness. A tube welded only on one face behaves very differently from one welded all-around, because the load path must transfer through bending, torsion, and shear in every direction. That’s why tubular connections so often pair the all-around circle with a groove or combination groove/fillet symbol, defining both the weld geometry and its full extent in one callout. Think of handrail posts, truss chords, and machine frames.

Automotive, Handrails, and Sanitary Stainless

Automotive exhaust systems, chassis brackets, and roll cages lean on the symbol for fatigue resistance — a partially welded exhaust joint cracks at the weld toes under constant vibration. Handrails, guardrails, and gate frames use it to keep water out of the tube interior, which is why weld quality and finish matter as much as strength. Food, beverage, and pharmaceutical stainless fabrication is the pickiest of all: hygienic tubing must be welded continuously and often purge-backed so there are no crevices where bacteria can hide. Sanitary lines are frequently TIG welded, where polarity and heat control decide whether the inside surface stays smooth. Because these are repetitive circumferential joints, this is exactly where automation shines — heavy, high-deposition work is well suited to robotic submerged arc welding, and consistent technique on the manual side benefits from deliberate welding practice.

Quick Note: If a drawing shows all-around on a tubular joint, check whether it’s paired with a groove or combination groove/fillet symbol — that callout tells you the joint prep as well as the wrap.

Reading the Symbol on Real Drawings: Field Welds, Tails, and Combinations

Specs are abstract until they land on a real drawing with a hundred other marks competing for attention. The circle at the arrow-to-reference-line junction is easy to miss, so the fastest way to build confidence is to walk through the same joints you’ll actually see in the shop.

Worked Example 1: All-Around Fillet on a Pipe Flange

Picture a 6-inch flange welded to a pipe. The arrow points to one spot on the joint, but a fillet symbol with a leg dimension—say 6 mm—sits above the reference line, and the circle sits at the junction. The circle tells you the leg size applies to the entire circumference, not just where the arrow touches. You don’t read it as “6 mm here and figure out the rest”; you read it as “6 mm everywhere, 360 degrees.”

Before you strike an arc, any weld like this still runs through your qualified procedure and technique fundamentals—details covered in our guide to building real welding skills. The symbol just tells you the intended geometry.

Worked Example 2: All-Around Groove on a Tube-to-Plate Joint

Now a tube set into a plate with a groove symbol. Groove welds carry their size differently—the groove size or depth goes to the left of the symbol, the groove type is the symbol itself. Add the all-around circle and the groove wraps the full tube circumference. This is where fit-up and tack placement matter, because a full-penetration groove all the way around leaves no room to hide a cold root.

Adding the Field Weld Flag

Combine the all-around circle with a field weld symbol—the little flag on the reference line—and you’ve specified that the all-around weld is made in the field, not in the shop. That single combination changes logistics: field conditions, weather, access, and inspection all enter the picture. The flag and the circle stack cleanly on the reference line, and both apply to the same joint.

The Tail and Process References

The tail is the forked section at the far end of the reference line. Your process reference lives there—GTAW, GMAW, FCAW, SAW. When you see an all-around note and a tail reference together, you’re being told both the coverage (all around) and, often, the process to use. That matters on austenitic stainless and aluminium work, where process and polarity choices drive quality—see our breakdown of TIG polarity for precision welds.

Combination Symbols Sharing One Circle

Frequently a groove and a fillet share one reference line and one all-around circle—for example, a full-penetration groove finished with a reinforcing fillet, applied continuously around the joint. Here the circle governs both welds. Read the sizes separately: groove size on the left of the groove symbol, fillet leg on the left side of the fillet symbol.

What Happens When Length or Pitch Conflicts With All-Around

This is the classic trap. A length or pitch number (like 50-100 for intermittent welding) next to an all-around circle is contradictory—all-around means continuous, no gaps. If you see both, stop and get a clarification. Either the welder welds a full continuous loop, or the detailer intended an intermittent weld and the circle doesn’t belong. Never guess.

Quick Note: Under AWS A2.4:2020, multiple sub-reference lines are permitted to designate a groove weld that extends around a joint where the joint type changes. Contour rules were also updated: contour may be achieved by any method, the flat symbol is limited to fillet welds, and the flush symbol is used for groove, plug, and slot welds. The dimension left of spot and seam symbols now designates only weld size.

Get comfortable with these five patterns and the circle stops being a smudge. It becomes a clear instruction.

Common Mistakes and Misunderstandings That Cause Costly Rework

Most all-around errors don’t happen at the arc — they happen at the drawing. A misread symbol sends a welder down the wrong path, and by the time anyone catches it, you’re grinding out a finished joint. Here are the mistakes that cost the most money.

“All Around” Is Not “Both Sides”

The single most common misread is treating the all-around circle as a “weld both sides” instruction. These are distinct concepts. Both sides is communicated through a weld symbol placed on both the arrow side and the other side of the reference line, each with its own size and length. All around means the joint is welded continuously around its entire perimeter. Confuse the two and a welder may lay a full pass on each face but leave the corners and closures open — a partial loop that looks complete on a quick inspection.

Treating an All-Around Weld as Intermittent

The all-around notation is generally incompatible with intermittent weld notation, because a continuous perimeter loop has no defined pitch. If a drawing awkwardly combines the circle with a length-and-pitch callout like “3-9,” the fabricator faces an impossible instruction. Clarify with the designer before cutting metal — never guess. Treating a 360-degree weld as skip or stitch welding leaves gaps that trap moisture and defeat the purpose of a sealing or pressure joint.

Quick Note: If the all-around circle shares a reference line with a pitch or length dimension, stop and get written clarification. That combination is a red flag, not a real instruction.

Losing the Circle at Low Resolution

Small symbols like the all-around circle can vanish at low resolution or on a faded print, prompting incorrect arrow-side-only welding. This is especially dangerous on scanned shop drawings viewed on a tablet or phone. Zoom in, check the printed PDF at full size, and if the junction of arrow and reference line is unreadable, request a clean file. A pixel of ink can mean hours of rework.

Applying All Around Where Access Fails

Detailers sometimes call out an all-around weld on geometry where tooling or access makes a full loop impossible — a tube socketed into a closed plate, or a fitting against a backing bar. The welder then either stops short, creating a defect, or forces an awkward closure with poor fusion. Always confirm weld access and backing removal at the closure point before committing. Planning the start-stop overlap is part of the job, not an afterthought.

Shop and Field Interpretations Drift Apart

A detailer’s omission or a corrupted CAD library symbol can propagate straight to the floor. One shop reads the drawing as a full loop; the field crew reads it as arrow-side only. The mismatch surfaces at final inspection, when the joint is fully assembled and hardest to fix. Standardizing your symbol library to the governing edition of AWS A2.4 and ISO 2553 prevents that drift.

Over-Welding Creates Its Own Defects

Once a welder commits to “weld it all the way around,” the temptation is to pile on metal. Excess fill on a continuous all-around joint can contribute to distortion and surface defects such as overlap, where weld metal rolls onto the base metal without fusing. That’s a rejectable defect, not extra insurance. If your loops keep failing on profile, tune your travel speed and settings — see our guides on contact tip welding and good vs. bad MIG welds, and review the dedicated overlap welding defect article before the rework pile grows.

Verification Checklist Before You Strike an Arc

Confirm the governing standard (AWS A2.4 or ISO 2553) and its edition.
Re-read the reference line — is the symbol on the arrow side, other side, or both?
Confirm dimensions: size, length, and whether any pitch callout was mistakenly paired with the circle.
Verify weld access and where you’ll blend the closure.

Getting these four checks right takes a minute. Skipping them costs a shift. Build the habit while your skills are still developing — a strong foundation in welding practice pays off every time a drawing throws a small symbol at you.

Inspecting and Verifying All Around Welds: NDT and Acceptance

You can draw a flawless all around symbol, but somebody still has to prove the weld actually travelled the full perimeter. That’s the inspector’s job — and it starts before any gauge or X-ray machine comes out.

Visual examination (VT) is the first check that a weld is truly continuous around the whole perimeter rather than stopping at the arrow side. An inspector walks the joint, confirming a sound, uniform bead at every clock position — no gaps, no unwelded stretch hiding behind a bracket, no weld that quietly ended where the arrow pointed. On pipe and tube, that means watching for a consistent cap, matching leg sizes, and a clean tie-in where the start meets the finish. A stopped-short weld is easy to miss on a busy assembly, which is exactly why the symbol exists. Spotting defects early, like an overlap welding defect, saves far more than it costs.

Good lighting, a weld gauge, and a magnifier are basic VT tools. Check for full penetration at the tie-in, consistent reinforcement, undercut along the toe, and any crater left at the stop point — the classic weak spot on an all-around joint.

Once VT passes, the code or the drawing decides what else is required. Common volumetric and surface methods for circumferential welds include radiographic testing (RT), ultrasonic testing (UT), magnetic particle testing (MT), and penetrant testing (PT). Each answers a different question:

RT — film or digital radiography looks through the full thickness, ideal for circumferential pipe welds where internal porosity, slag, or lack of fusion matter.
UT — shear-wave ultrasound detects planar defects like lack of fusion and cracks, and suits thick-wall circumferential joints where radiography struggles with defect orientation.
MT — magnetic particle testing finds surface and near-surface discontinuities in ferromagnetic steel; excellent for the toe of a fillet running around a boss.
PT — penetrant testing does the same job on austenitic stainless and aluminium where MT won’t work.

Extent matters as much as method. A drawing might call for 10% random RT, 100% UT on a critical ring, or full MT at a specific joint. Because an all-around weld has no natural stopping point, inspectors often divide the circumference into quadrants and sample deliberately rather than clustering shots near the easiest access. If any sample fails, the code usually triggers additional examination of the same weld and the welder’s other work.

Acceptance criteria for structural and pressure welds are typically governed by codes such as AWS D1.1 and the ASME Boiler and Pressure Vessel Code or ASME B31 piping codes. D1.1 sets visual and nondestructive acceptance limits for structural steel, while ASME Section IX qualifies your procedure and welders and Section VIII or B31.1/B31.3 govern examination and acceptance for vessels and piping. The all-around requirement simply widens the exam scope: if 100% of a joint is welded, 100% of it becomes candidate for testing.

Quick Note: Nondestructive examination requirements can themselves be specified with AWS A2.4 symbols, which cover the examination method, frequency, and extent in addition to welding and brazing symbols. So a note on the tail can demand “RT 100%” just as precisely as the circle demands a continuous weld.

Note: Always confirm the NDT extent on the drawing before you finish — getting it wrong means re-inspection, not just re-welding.

Documentation closes the loop. Whether you’re welding tube fittings or a pressure vessel, record the procedure number, welder ID, examination method, extent, and results against the drawing. On code work, traceability isn’t optional — it’s what proves the all-around weld you inspected is the one in service years later.

None of this examination matters if the weld underneath is rushed. Consistent travel speed, correct polarity, and steady technique — the fundamentals covered in our welding practice guide — are what let a joint survive RT and UT in the first place. Compare your finished beads to the marks of good and bad MIG welds before the inspector ever arrives.

Best Practices for Welders, Detailers, and Fabricators

The weld all around symbol is small, but the decisions behind it split cleanly into two camps: the people who draw it and the people who burn it in. Get both halves right and circumferential joints come out consistent, clean, and inspection-ready. Get them wrong and you’re grinding out a closure defect at midnight. Here’s the practical playbook for each side of the print.

For Detailers and Designers: Draw It So It Can’t Be Misread

Placement is everything. The all-around circle belongs exactly at the junction of the arrow line and the reference line. Put it anywhere else — floating off the tail or drifting toward a leader — and the welder has to guess whether you mean a full loop or a localized weld. According to AWS A2.4, that junction location is what signals “weld all around” as opposed to a discrete length.

A few habits keep drawings clean:

Pick one standard and stay loyal. Choose AWS A2.4 or ISO 2553 and don’t blend them on the same print. Mixing conventions invites misinterpretation.
Call out twist and allowable distortion for all-around tube and box joints, or the shop will default to whatever keeps the part straightest.
Flag field-weld conditions — access, position, and whether the loop can actually be completed in situ.

One more discipline: keep revision control tight. A single moved circle changes scope from a few inches of weld to a full perimeter, so reissue clean prints rather than redlining by hand. The 2020 AWS A2.4 revision refined symbol conventions; know which edition your shop works to.

Quick Note: A symbol that ignores weld access is only half a specification. If a welder can’t physically reach 360°, the drawing needs a note, not a surprise in the field.

For Welders: Plan the Loop Before You Strike an Arc

Continuous circumferential welds live or die on planning. Decide where you’ll start and stop, and stagger the closure so the weld doesn’t terminate on top of its own start. This single habit cuts the risk of a defect at the point where the weld meets itself.

On thin-wall tube and box sections, heat is your enemy. Control heat input and interpass temperature to limit distortion and burn-through, and keep travel speed steady around the loop. For fit-up on tube work, our guide to weld tube fittings walks through prep that pays off here. Choose your polarity deliberately — see TIG welding polarity for how DCEN, DCEP, and AC change the arc on the closure. And if you’re running flux-cored, brush up on DCEN vs DCEP for flux core so your root behaves predictably.

Access matters as much as technique. Check that your gun or torch angle and body position let you carry the loop without stopping; reposition the part with a positioner if a full pass would otherwise stall halfway.

Clean technique starts long before the arc. A tidy, well-lit booth, PPE you trust, and reps on scrap metal all feed into repeatable loops. Build those habits with our welding practice guide, set up a compliant space using welding facilities planning, and protect your eyes per our protective eyewear guide. Not sure a closure is acceptable? Compare it against good and bad MIG welds before you sign off.

Automate the Repetition

When the same all-around joint rolls past your station hundreds of times, hand welding stops making sense. Repetitive circumferential welding can be automated, and robotic submerged arc welding handles high-deposition, heavy-duty loops with consistent start/stop positions — the machine never forgets to stagger the closure. For high-volume flux-cored loops, dial in your torch consumables — worn contact tips ruin arc stability on a long circumferential pass.

Simple rule: draw it clearly, plan the loop, control the heat, and automate the repeat work. Do that and the all-around symbol stops being a trap and starts being a spec you can hit every time.

Conclusion: Getting the Weld All Around Symbol Right Every Time

A single small circle no bigger than a pencil eraser can quietly redefine an entire fabrication job. Parked at the junction where the arrow meets the reference line, it declares that the weld must run continuously around the full perimeter of the joint — not merely where the leader happens to point. Miss it, and you may under-weld a part that looked perfectly fine on the drawing; read it correctly, and you build exactly what the engineer intended — on time, to code, and without a costly rework.

That is the whole story of the weld all around symbol. It is a supplementary symbol that modifies the associated weld symbol, expanding a local weld into a 360-degree, uninterrupted one. Every placement rule, standard difference, and inspection step covered in this guide flows from that single idea. Get it right, and the rest of the notation falls into place.

The Distinctions That Matter

Before you strike an arc, confirm four things:

All-around circle vs. tail text. The circle sits at the arrow-to-reference-line junction; written instructions like “weld all around” live in the tail.
Both-sides welds. A symbol on each side of the reference line means two separate welds — not one running around.
Intermittent welds. Length-and-pitch dimensions (say, 3–9) call for a stitch pattern, which is the opposite of continuous.
Field welds. A flag at the junction signals site welding, which can stack with — but never replaces — the all-around requirement.

Then check the governing standard. Because AWS A2.4 and ISO 2553 differ in how they draw and position symbols, the drawing’s cited standard decides interpretation. Keep a current chart nearby — the AWS A2.1 welding symbol chart that accompanies AWS A2.4 is a shop-floor favorite — and know where ISO 2553 lands for European and international work. A quick glance at the legend now can prevent an expensive misread later.

Quick Note: A circle at the junction of arrow and reference line means “weld around the entire perimeter.” If you only see the requirement written in the tail, the circle is missing — clarify with the designer before welding.

Why It Pays to Get It Right

Misreading the symbol is never cheap. An all-around weld that gets executed as a single-side pass can leave a pressure boundary that weeps, a structural connection that fails inspection, or a code violation that forces a full rework. Correct interpretation, execution, and inspection protect structural integrity, leak-tightness, and code compliance — three things no schedule can absorb losing. That discipline is simply the same skill set behind building real welding skills through deliberate practice, applied with a sharper eye for notation.

Your Pre-Arc Checklist

Read the standard block to confirm AWS or ISO governs the drawing.
Locate the circle at the arrow/reference-line junction and confirm the perimeter to be welded.
Distinguish arrow side vs. other side, and rule out both-sides and intermittent notation.
Check the tail for process, NDT, and field-weld instructions that stack with the circle.
Plan the sequence to control distortion on closed joints, such as weld tube fittings and pipe joints.
Verify the full perimeter — visually and with the specified NDT — before signing off.

Whether you’re detailing drawings at the drafting table or laying beads on the shop floor, keep the current symbol chart within arm’s reach. And remember the basics that keep you working cleanly and safely all day: knowing your amperage and polarity, as reviewed in our guide to DCEN vs DCEP polarity, and wearing proper protective eyewear for welding. Get the all-around symbol right, and the small circle becomes exactly what it should be: a clear, unambiguous instruction you never have to second-guess. Treat the checklist above as a habit rather than a one-off exercise, and this symbol will never slow you down.

Frequently Asked Questions

What does the weld all around symbol look like?

It is a small circle placed at the junction where the arrow line meets the reference line of a welding symbol. The circle is a supplementary symbol that tells the welder to apply the specified weld continuously around the entire perimeter of the joint.

Does the all around symbol mean weld on both sides?

No. ‘All around’ means continuous welding around the full perimeter or circumference of the joint, while ‘both sides’ refers to welding on the arrow side and the other side of a joint. These are separate concepts and are not interchangeable.

Where exactly is the all around symbol placed?

It is drawn as a circle at the bend or junction of the arrow line and the reference line. Its location there distinguishes it from weld symbols placed on the reference line itself, which describe the weld type and geometry.

Is the all around symbol the same in AWS A2.4 and ISO 2553?

The circle concept is similar, but the surrounding conventions differ. AWS A2.4 uses a single reference line, while ISO 2553 offers a dual-reference-line system (System A) and a single-reference-line system (System B). Always interpret the symbol according to the standard cited on the drawing.

Can the all around symbol be combined with a field weld symbol?

Yes. The all-around circle can appear together with the field weld flag, which indicates the weld is made at the site rather than in the shop. The combination tells the fabricator the weld is both continuous around the perimeter and performed in the field.

Does all around mean the weld must be full penetration?

Not by itself. The all-around symbol only defines the extent of welding around the perimeter. Penetration requirements come from the specific weld symbol, its dimensions, and the governing code or specification.

Can the all around symbol be used with intermittent welds?

Generally no. A continuous weld around the entire perimeter has no pitch or spacing, so combining it with intermittent notation is contradictory. Intermittent welds are used where welding is intentionally segmented.

How is an all around weld inspected?

Inspection starts with visual examination to confirm the weld is continuous around the full perimeter, followed by methods such as penetrant, magnetic particle, ultrasonic, or radiographic testing as required. Acceptance criteria come from the applicable code, such as AWS D1.1 or the ASME Boiler and Pressure Vessel Code.