Can Ends & Tabs: Beverage Grades & Coatings

Written by: John LauChecked by: MarkSeptember 28, 2025

Can Ends & Tabs: Beverage Grades & Coatings

Scope & who this is for. This cluster page is a practical, line‑side, engineer‑friendly guide to aluminum beverage can ends and tabs—centered on 200/202 B64 SOT/LOE formats used by craft and high‑speed fillers. We summarize alloys and tempers used for end/tab stock, what “B64 / SOT / LOE” actually mean on your seamer sheet, how score residual and lever geometry drive opening force, what double‑seam dimensions really control, and how to choose BPA‑NI coating families for beer, CSD, energy, and juices in light of current EFSA/FDA positions. We also link out to supply‑chain topics (MOQ/lead times, DDP packaging) so purchasing and QA can align with production.

What you’ll get in 9 minutes: a quick decoding of end/tab nomenclature, a one‑page alloy/coating crib, two interactive tools (Opening‑Force & Score Residual Estimator and Coating Suitability Checker), rules of thumb for seam setup, and validated references (PDFs where possible) you can forward to your OEM, canmaker, or auditor.

1) Decoding 200/202 B64, SOT & LOE

Diameter codes. In modern beverage ends, “200” ≈ 50 mm and “202” ≈ 52 mm outside curl diameters. Most craft lines run 202 ends on 211 or 204 cans; slim formats may use 200. OEMs publish dimensioned spec sheets (curl diameter/height, panel height, countersink depth) that your seamer setup must track against. Compare with crown finishes for glass here when you plan mixed packaging.

Profile code “B64”. “B64” defines the seaming profile and chuck geometry the end is designed to run with (tooling radii, hook length window, etc.). Your end supplier’s drawing and “recommended double seam specs” are the source of truth for target seam thickness, cover hook, body hook, overlap, and countersink. For 202 B64 LOE ends from major makers (Ball, Ardagh), you’ll often see downloadable spec PDFs bundled with seaming recommendations—use those, not generic numbers.

Stay‑On‑Tab (SOT) & LOE. “SOT” means the tab remains attached after opening for safety; “LOE” = large opening end (higher pour area, common in craft). These affect score geometry and required opening force: LOE patterns increase pour aperture but can raise sensitivity to score residual and tab leverage. On high‑CO₂ products, verify vent score tuning so the initial pop vents before main score tears.

Typical call‑outs you’ll see on a 202 B64 drawing

Curl OD / curl opening / curl height
Countersink depth (CSD)
Panel height
Score land width & residual (primary & vent)
Tab rivet diameter & location
Seamer setup targets (thickness, overlap, hooks)

Associated vocabulary

Cover hook = end hook; body hook = can body hook.
Overlap = minimum interlock length required for hermeticity.
Countersink = distance from top of curl to panel; relates to buckle resistance and stackability.
Score residual = remaining metal under the score; major driver of opening force & tear propagation.

LOE vs standard pour — what actually changes on line?

Pour area. LOE increases aperture, improving aroma release and pour speed for craft styles.
Score geometry. Wider arc and tailored vent path; often requires different opening‑force window.
Tab design. Nose shape and leverage vary; verify lift/tear forces on your test bench.
Seamer feel. Same profile code (B64) but countersink and curl details may differ—don’t reuse old setup blindly.

Internal navigation: You’ll see contextual links to related clusters throughout, e.g., food‑contact DoC and supply/packaging topics relevant to cans and closures.

2) Alloy families & tempers for ends and tabs

Why 5xxx alloys? Beverage end stock and tab stock rely on Mg‑bearing aluminum (5xxx series) for a balance of formability, strength, and corrosion resistance after coil coat + bake. Two work‑horse chemistries dominate:

AA5182 (≈4–5% Mg): popular for ends and tabs; excellent strength after H19/H48 work‑hardening and coil coating. Good buckle resistance when paired with proper countersink.
AA5052 (≈2.5% Mg): used in some tab and end applications; slightly lower strength but very good corrosion resistance and drawability in selected tempers.

Tempers you’ll encounter. H19 (full‑hard), H48 (special temper often noted on canstock data sheets), and variant coil‑coat tempers. Practical takeaway: design opening force with the delivered score residual + tab leverage, not just nominal alloy strength—coating bake and line handling shift properties slightly.

One‑page alloy crib for beverage ends & tabs

Alloy/Temper	Typical use	Why chosen	Notes for QC
5182‑H19/H48	Ends & tabs	High work‑hardening for buckle resistance; good corrosion behavior with proper coating	Watch Mg pick‑up during recycling; confirm film weight & cure to avoid under‑film corrosion
5052‑H19	Tabs (select)	Good formability; adequate strength for many SOT designs	Verify tab rivet pull & lift forces on your exact score pattern
3xxx variants	Some proprietary tab/end stocks	Balanced strength with alternative chemistries	Treat as supplier‑specific; validate on line

Supplier validation routine. When switching alloys or suppliers, lock a 3‑run PPAP‑style (incoming cert + film weight + cure + opening‑force + seam teardown) and keep your filler, seamer, and pasteurizer heat maps identical between lots so you can attribute variability correctly.

For hot‑filled or acidic beverages, alloy choice matters less than coating family, film weight, and cure. Jump to the coatings section for a structured selection method, plus a tool that turns your product matrix into a coating short‑list.

3) Opening mechanics: score residual, tab leverage & venting

Three numbers dominate the “feel” of an end: (1) score residual on the main score (µm), (2) score land width (mm) and included angle, and (3) effective lever arm from tab rivet to nose. Opening force (F_open) scales with the remaining section under the score times the strength of the work‑hardened alloy, tempered by real‑world factors (panel bulge with CO₂, tab flex, coating). A simplified engineering relation many teams use for sanity‑checks is:

Rule‑of‑thumb (sanity‑check, not a spec): F_open ≈ k · σ_y · (t_res · w_score) · (1/ℓ_tab), where σ_y is yield stress of the scored ligament, t_res the residual thickness, w_score land width, and ℓ_tab the effective lever arm. “k” lumps geometry and bending/shear mix. Reduce t_res or increase ℓ_tab to decrease opening force—within abuse and burst constraints.

Venting first. The vent score (shallower, upstream) should release pressure before the main score initiates, avoiding blow‑offs on gassy products. If your “pop” feels harsh or sprays, you may have vent score depth variation or panel bulge from warm filling; work with your canmaker to adjust vent residual and tab geometry.

How to measure opening force consistently

Instrument. Use a calibrated force gauge with a hook fixture sized for your tab opening. Follow your end supplier’s test method (jaw speed, angle, sample conditioning).
Conditioning. Stabilize samples at fill temperature ±1 °C and CO₂ volume. If you change temperature or carbonation, you are changing the test.
Sampling. Pull at least n = 10 per lot and per pasteurizer zone (inlet/mid/outlet) if you pasteurize; panel bulge differs across the tunnel.
Outlier rule. Flag any tear‑through (no vent) as a critical defect; repeat with fresh samples and hold the lot pending canmaker review.

What changes opening force the most?

Score residual (µm): biggest single lever—small reductions can flip “hard openers” to spec, but do not chase comfort at the expense of abuse resistance.
Tab leverage (mm): longer rivet‑to‑nose lever reduces force; ensure no rivet pull‑out or nose slip.
Product temperature and CO₂: warmer, higher‑gassed product pre‑bulges panels—typically lowers initial force but can spike spray if vent timing is off.
Coating friction: different systems slightly alter tear propagation; validate any coating change on your matrix.

Interactive tool — Opening‑Force & Score Residual Estimator

Opening-Force & Score Residual Estimator

Quickly sanity-check how score residual, land width and tab leverage shift opening force.

Score residual t_res (μm):

Score land width w (mm):

Tab effective lever arm ℓ (mm):

Ligament yield σ_y (MPa):

Geometry factor k (–):

Acceptance windows. End makers define opening‑force windows by beverage style and end pattern. Always use the supplier’s spec for release, and run line‑side pull/lift checks per lot. If you change fill temperature or CO₂ volumes, re‑confirm—panel bulge reduces effective score residual at open.

4) Coatings: epoxy vs BPA‑NI (acrylic, polyester, epoxy‑mimic)

What the coating must do. Prevent metal‑product interaction (taste corrosion, pitting), survive forming and pasteurization/retort, protect the score from under‑film corrosion, and keep migration below regulatory limits. You’ll see three big families offered today for beverage interiors: water‑borne acrylics (widely used for D&I inside spray), polyesters (common in food cans, expanding in beverage), and non‑BPA epoxy technologies designed to mimic legacy epoxy phenolics.

Regulatory snapshot (late‑2024/2025 context). EFSA re‑evaluated BPA in 2023 and dramatically tightened the tolerable daily intake; the European Commission adopted a ban for BPA in food‑contact materials in December 2024, with transitional arrangements. By contrast, the U.S. FDA (as of 2023–2024 updates) still permits approved BPA uses and maintains that current uses are safe, while monitoring new evidence. Many canmakers therefore offer BPA‑NI systems (e.g., PPG Innovel® lines; Sherwin‑Williams valPure® V‑series) specifically for beverage ends and inside sprays.

How to qualify a coating change (practical plan)

Document pack. Get DoC, film weight target, cure window, and migration test summaries from the supplier for your exact SKU.
Oven mapping. Instrument your inside‑spray or end‑cure oven; lock time‑at‑temp profiles with 3‑point thermocouples at slow/nominal/fast line speeds.
Sensory. Run triangle tests on worst‑case SKUs (highest IBU, highest acidity) against your current coating.
Corrosion. Pasteurize/retort worst‑case products and hold at elevated temperature; cross‑section a subset to check under‑film corrosion at scores.
Line trial. Validate seamer performance (tear behavior, vent timing) and opening‑force across two lots; approve only after stable results.

Coating families — quick matrix

Family	Typical beverage fit	Heat profile	Notes
Acrylic (BPA‑NI)	Beer, CSD, energy; 2‑pc D&I inside spray	Oven cure; line‑speed friendly	Flavor‑neutral, low migration; validate with your pasteurization curve
Polyester (BPA‑NI)	Juice/acidic, some retortable SKUs	Higher film weights; robust under acid	Check flexibility at scores/radius; confirm taste neutrality on your matrix
Non‑BPA “epoxy‑mimic”	General beverage & closures	Designed to match legacy epoxy performance	Offered as valPure® V70, etc.; verify migration/NI claims in DoC

Interactive tool — Coating Suitability Checker

Coating Suitability Checker (Beverage Ends & Inside Spray)

Map your product matrix (pH/CO₂/heat) to plausible coating families before talking to your canmaker.

Beverage type:

Product pH:

CO₂ volumes (vol):

Thermal regime:

Documentation to request. Always collect (a) current Declaration of Compliance matching your country/region, (b) migration test summary for your intended use, (c) film weight and cure window for the coating, and (d) confirmation that end/tab parts you order are built with that coating (SKU‑level traceability). See our Food‑Contact DoC cluster for a template you can reuse with canmakers.

5) Double seam fundamentals that protect your product

Why it matters. The double seam is a five‑layer interlock (3 thicknesses of the end curl + 2 of the body flange) with compound sealing the voids. Proper first‑op and second‑op settings put each dimension—cover hook, body hook, overlap, seam thickness, and countersink—inside a window that delivers hermeticity without over‑work or buckles.

Core dimensions & quick sanity‑checks

Dimension	What it tells you	Quick check
Seam thickness	Overall tightness (w/ compound)	Compute “no‑compound” baseline: 2×body + 3×end metal; compare to measured
Cover hook	How much end metal turns under	Too small = leakers; too large = false seams/pleats
Body hook	How much body turns into seam	Short body hooks reduce overlap; watch neck‑in alignment
Overlap	Interlock safety margin	Keep inside supplier’s recommended min; don’t crowd the window
Countersink	Buckle resistance & stack height	Lower CSD increases buckle; verify after second‑op

Teardown SOP for line techs

Sampling: Pull 5 cans per head across the turret; add 5 from pasteurizer outlet after thermal cycling.
Cut & polish: Section per supplier method; polish to reveal hook tips and compound pocket.
Measure: Record seam thickness, cover hook, body hook, overlap, countersink; compute theoretical no‑compound thickness.
Photograph: Archive macro images with scale and head ID; store with batch and date.
Decision: Release only if all dims hit the window and wrinkle ratings pass; otherwise adjust first‑op (geometry) then second‑op (tightness).

Acceptance criteria & what to adjust

Symptom	Likely cause	Primary adjustment
Thin seam, leakers	Insufficient second‑op or low compound	Increase second‑op slightly; verify compound weight and viscosity
False seams/vees	First‑op too tight or misaligned	Reset pin height; reduce first‑op; inspect rolls for wear
Excessive droop	First‑op geometry poor	Increase first‑op lightly; check chuck radius
Wrinkles in body hook	Over‑tight second‑op or flange issues	Back off second‑op; verify flange width and squareness

Practical line notes. Pin height sets the base geometry for both operations; confirm with gauge blocks and your end spec’s setup sheet. Re‑verify after any lift table or chuck change. Train techs to compute the “no‑compound” seam thickness (2×body + 3×end) for a plausibility check when troubleshooting leaks.

6) Seamer setup & supplier specs: use the drawing, not folklore

Start from the canmaker’s PDF. Ball and others publish 202 B64 end drawings and “recommended double seam specs.” Use these as initial settings, then qualify on your machine to hit product specs (not merely machine specs). Keep a laminated copy of your current spec + torque diagrams at the seamer.

Lock in pin height per can/end combination before first‑op roll preload.
Adjust first‑op to achieve correct hook lengths and smooth lap; correct droops before tightening second‑op.
Second‑op tightens to thickness window without crushing compound; do not “chase” leaks with excessive second‑op.
After thermal cycles (pasteurizer or warm room), re‑measure seam; countersink will shift slightly.

When you change end type (e.g., switch from 202 SOT to 202 LOE) or coating family (epoxy → BPA‑NI), re‑run your seam matrix and opening‑force checks. Coatings with different friction can subtly change score tear characteristics.

7) Supply chain: MOQ, lead times & packaging (DDP)

MOQ & line alignment. Ends/tabs are highly tooled components; paint color, tab style, and liner system all drive MOQ. Coordinate promotions (black ends, colored tabs) with your minimum layer/sleeve counts to avoid partial pallets and handling scrap. For procurement planning strategies, see MOQ & lead times.

DDP packaging. End sleeves and pallets have specific stack heights and corner‑protectors; BPANI vs epoxy liner SKUs may have different layers/sleeve counts. Align your warehouse racking and FIFO with supplier pallet maps. If you ship internationally, review our DDP packaging for closures to copy carton/bag/pallet labeling rules to can ends.

Cross‑format planning. If your portfolio spans aluminum cans and glass, read the crown caps cluster to design a single QA protocol for CO₂ retention and opening torque/force across both packages.

Receiving checklist (ends & tabs)

Verify SKU and coating family on pallet labels; cross‑check against approved list.
Confirm sleeve count, layer count, and pallet height; document any deviations before breaking wrap.
Randomly sample for curl nicks, paint/ink defects, and tab rivet height; quarantine if damage exceeds your AQL.
Record humidity/temperature at receiving; high humidity plus cold storage risks condensation and SCC.
First‑article: run opening‑force and seam checks before releasing the lot to production.

Pallet handling & storage rules

Keep pallets on flat, clean surfaces; no stacking beyond supplier’s map.
Use clean gloves when handling; avoid oils/solvents not approved by the canmaker.
Once a sleeve is open, cover with clean plastic if not consumed within the same shift.
Rotate FIFO by coating family first to minimize mixed‑liner runs.

Hygiene & handling. Ends/tabs are precision parts. Avoid contact with oils/cleaners not approved by your canmaker. Keep sleeves sealed until use and cover partially used sleeves. Train operators to reject ends with nicks at the curl or visible score damage.

Root‑cause quick map (line‑side)

Symptom	Ask first	Likely culprit
Spray on opening	Product temp & CO₂?	Vent score depth variation; warm fill; panel bulge
High opening force	New end lot or coating?	Score residual too high; shorter tab lever; coating friction
Random leakers	Which heads?	Head‑specific first‑op drift; worn rolls; pin height
Rust at score after warm hold	Film/cure OK?	Under‑film corrosion from low film weight or under‑cure

9) Sustainability: coatings, alloys & recycling

Recycling realities. Beverage can streams already operate closed‑loop at high rates; tabs/ends made from 5xxx alloys are compatible with the stream, though Mg content requires appropriate melt management. Coatings, whether epoxy‑based or BPA‑NI, are designed to burn off in the remelt and meet emissions controls. If you report ESG, align your LCA system boundaries (collection/sort/remelt yields) to avoid apples‑to‑oranges comparisons with glass or PET.

10) FAQ — fast answers you can share with your team

What’s the clean way to compare ends from two suppliers?

Use the supplier drawing as your target; run three lots per supplier; keep the same filler/seamer/pasteurizer settings; measure opening force, seam teardown, and abuse/buckle per your product worst‑case (warmest fill, highest CO₂, longest pasteurization). Ask both suppliers for identical coating family, film weight, and DoC. Decide on total cost of ownership (quality hits + line availability), not unit price alone.

Do BPA‑NI coatings change taste?

Modern acrylics and BPA‑NI epoxy‑mimics are formulated for flavor neutrality in beer/CSD. Always run sensory on your product matrix—especially for hop‑forward beers or acidified SKUs—and lock your oven cure window (under‑cure can drive taste issues and corrosion).

Why did our seam thickness look okay, but we still had leakers?

Seam thickness alone isn’t enough—check cover/body hook, overlap, and wrinkle rating. Verify pin height and seamer tool wear. Confirm that the ends on that lot match your current end spec (paint color changes sometimes come with different liner families).

Can we mix 200 and 202 ends in the same plant?

Yes, but avoid cross‑pollinating chucks/rolls and setup sheets. Use color‑coded changeover kits, and store sleeves by end diameter and liner family. Train techs to verify curl OD and panel height on receipt.