Post your weld, let people rate it. Be nice-ish.
FIELD REFERENCEBETA
Welding, rigging, shop and field. Start with Rods & wire for amps, polarity and tips on the exact rod or wire, or jump to the tools below.
Beta version. Still being built and checked. Charts and settings are starting points only: your WPS, the code and the manufacturer's data always win. Spot a mistake? Email support.
6 processes · 40+ rods & wires · rigging · shop · signals · certs · jobs
Pick a process. Each one leads to a size chart, then classification. New to the letters and numbers on the box? See how to read them below.
Grouped by tensile strength — the first two digits (60 = 60,000 psi, 70 = 70,000 psi minimum tensile). "Not typical this size" means that classification isn't commonly stocked at the diameter you picked.
Same AWS classification = same weld chemistry, and sizes run the same across brands — only the trade name changes.
What each trade does, how much you weld in it, and how long the apprenticeship runs. For dispatch, the job line and signing the books, contact your local hall directly.
Welding work by state. Called the hall's job line or talked to the contractor? Tap Still open or Filled so everyone knows how fresh a post is.
Look up a term, pull a code chart, or get set up on pulse MIG, a torch, plasma, air arc, an LN-25 or TIG.
Diagrams are cross-sections unless marked top view. Red marks the problem; amber marks the part being named.
Quick references. Your WPS, the contract documents and your code edition always win over these charts.
Prequalified minimums for structural steel by steel category and the thickest part at the point of welding. Find your steel and process in the left column, then read across.
Values from the D1.1 prequalified preheat table (Table 5.8 in D1.1:2020; earlier editions number it differently), as reproduced in UFC 3-320-01A, Table 3-1. Confirm against your edition.
Cr-Mo steels harden and hydrogen-crack much more easily than carbon steel, so they need heat before the first arc and between passes. These are common quick-reference ranges for piping; the ASME code and your WPS set the actual minimums.
| P-No. | Material | Common grades | Preheat |
|---|---|---|---|
| P-4 | 1-1/4 Cr - 1/2 Mo | P11, F11 | 300–390°F150–200°C |
| P-5A | 2-1/4 Cr - 1 Mo | P22, F22 | 390–480°F200–250°C |
| P-5B / P-15E | 9 Cr - 1 Mo - V | P91 | 390–570°F200–300°C · 390°F minimum |
Source: Tempil preheat quick reference. Keep Cr-Mo at preheat until post-weld heat treatment or a controlled slow cool, per the WPS.
PWHT (stress relief) heats the finished weld to below the steel's transformation range, holds it, and cools it slowly. It relaxes residual stress and tempers hard zones. Structural work under D1.1 rarely calls for it; pressure vessels and piping often do.
| P-No. | Material | Required (Sec. VIII UCS-56) | Hold temperature | Hold time |
|---|---|---|---|---|
| P-1 | Carbon steel | Over 3/4" (exceptions with preheat) | 1100–1200°F595–650°C | 1 hr/in, 1 hr min |
| P-3 | C - 1/2 Mo | All thicknesses | 1100–1200°F595–650°C | 1 hr/in, 1 hr min |
| P-4 | 1-1/4 Cr - 1/2 Mo | All thicknesses | 1200–1300°F650–705°C (B31.3) | 1 hr/in, 1 hr min |
| P-5A | 2-1/4 Cr - 1 Mo | All thicknesses | 1250–1400°F675–760°C (B31.3) | 1 hr/in, 1 hr min |
| P91 | 9 Cr - 1 Mo - V | All thicknesses | 1350–1425°F730–775°C | Per code, typically 2 hr min |
| P-8 | Austenitic stainless (304, 316) | Generally not required | — | PWHT can sensitize stainless and hurt corrosion resistance |
Sources: Welders Supply PWHT guide · ASME B31.3 Table 331.1.1 discussion · D1.1 PWHT summary. Codes differ by edition; follow the WPS.
What color plain carbon steel shows at a given temperature. Glow colors appear once steel is red hot. Temper colors are a thin oxide film that forms on clean, bright steel well before it glows.
Approximate values from common blacksmithing and heat-treating color charts. Charts differ by 50–100°F, and your screen won't show the colors exactly.
For a steel that isn't in the D1.1 table, CE turns the mill cert chemistry into one number for how hard and crack-prone the weld zone gets. Higher CE needs more preheat. Enter percentages from the mill test report. The example is a typical A572 Grade 50.
IIW formula: CE = C + Mn/6 + (Cr + Mo + V)/5 + (Ni + Cu)/15
| CE | Weldability | Typical preheat (rule of thumb) |
|---|---|---|
| Up to 0.45 | Good | Usually optional |
| 0.45–0.60 | Fair — hardening risk | 200–400°F |
| Over 0.60 | Poor — high cracking risk | 400–700°F, low-hydrogen process, often PWHT |
These bands are a common shop rule of thumb, not a code requirement. Thickness, restraint and hydrogen level all push the number up.
Pick the two metals you're joining. The result shows the usual stick rod and wire, and why.
Swipe sideways to see every column →
Tap any cell for the full rod and wire names. Key: NiCr-3 = ENiCrFe-3 / ERNiCr-3 nickel · 625 = ENiCrMo-3 / ERNiCrMo-3 · Ni-55 = ENiFe-CI · Ni-99 = ENi-CI · B2 / B3 = E8018-B2 / E9018-B3 (match the Cr-Mo grade) · None = can't be arc welded directly.
Why the filler for two different metals is often weaker, or a different metal altogether, than one side of the joint.
Post your weld, let people rate it. Be nice-ish.
Jobsite math, weights, rigging charts and bolts. Tap a group to see its tools, or search to jump straight to one.
Crane, truck and equipment signals, with the voice call for each. Tap a group, or search to jump straight to a signal set.
The machines a shop hand runs besides the welder: saws, brakes, shears, CNC tables, drills, cranes and stands. Dangers first for new hands, pro tips for the old ones.
Which cards and certs a job wants, what they mean, and how to get them, explained simply. New to this? Tap Start here.