M‑Cor Groove Assistant is a fast, engineering‑friendly tool for static axial/face glands. Enter an cross‑section (inches), choose target squeeze, set a max gland fill, and get groove depth (D), groove width (W), and a corner‑radius range—instantly.
SEE PHASE 2 RADIAL/BORE

Key features

• Cross Section presets in inches – Load a large preset list (100+ sizes supported) or type a custom value.

• Real‑time calculations – Depth D = (1 − squeeze) · C; width sized to meet gland‑fill limits with W ≥ 1.10·C.

• Fill validation – Achieved gland fill is computed and flagged if it exceeds your limit.

• Corner‑radius guidance – Default range 0.05·C … 0.20·C with easy overrides.

• Clear, compact UI – Built for quick iteration and design reviews.

• Made for static face seals – Aligned with common axial/face practices and engineering checks.

How it helps

• Speed up gland design for covers, end‑caps, and face‑seal applications.

• Reduce rework by validating squeeze and fill before you cut metal.

• Standardize decisions across teams with a simple, consistent calculator.

How it works

1. Select or enter the  cross‑section (C) in inches.

2. Set squeeze (%) and max gland fill (%).

3. Review D, W, and R‑min/R‑max.

4. Adjust until the tool confirms gland fill is within your limit.

Engineering note

This tool provides preliminary values for static axial/face glands. Always verify against your internal standards and vendor handbooks. Future versions will add radial glands, tolerance stacks, temperature/volume swell, and extrusion gap/pressure checks.

Why M‑Cor

M‑Cor has manufactured Teflon® (FEP/PFA) encapsulated O‑rings since 1987, serving biologics, pharmaceutical, semiconductor, and aerospace customers. We digitally measure, document, and certify every O‑ring you order—delivering the transparency critical applications require. Our U.S. manufacturing focus and engineering support help you move from concept to production with confidence.

Call to action

Try Groove Assistant now to size your axial/face gland. When you’re ready, request a quote for M‑Cor encapsulated O‑rings or contact engineering for application review.

M-Cor Groove Assistant — Phase 2 (Radial • Bore)

Instruction Sheet

Purpose
Size a radial O‑ring gland in a bore/housing. The tool returns:

• Radial gland depth (Dᵣ)

• Groove width (W)

• Corner radius range (Rmin…Rmax)

• Diametral clearance and achieved gland fill

Scope
Static and light‑to‑moderate dynamic face motion (sliding) in bore configurations. Units are inches.

1) What you need before you start

• O‑ring cross‑section, C (in) — AS568 in inches or your custom size.

• Bore ID, Dᵦ (in) — housing inside diameter.

• Shaft/Piston OD, Dₛ (in) — mating component outside diameter.

• Service — Static or Dynamic.

• Target squeeze (%) — typical ranges:

  • Static: 10–30%

  • Dynamic: 8–16%

• Max gland fill (%) — common target ≤ 85%.

• Optional: preferred corner radii. If blank, the tool uses 0.05·C … 0.20·C.

2) Field names (what to enter)

• O‑Ring Cross‑Section (C) — numeric inches (e.g., 0.139).
  Tip: Use the preset list or type any value; the input accepts 0.0001 increments.

• Bore ID (in) — e.g., 1.500.

• Shaft / Piston OD (in) — e.g., 1.490.
  Rule: Bore ID must be larger than Shaft/Piston OD.

• Service — choose Static or Dynamic.

• Target Squeeze (%) — enter your design target.

• Max Gland Fill (%) — often 85 for general static duty.

• Corner Radius Min / Max (optional) — leave blank to auto‑suggest 0.05·C … 0.20·C.

3) Outputs (how to read results)

• Gland Depth (radial), Dᵣ (in) — the groove “height” in the radial direction.

• Groove Width, W (in) — the needed axial width to honor the fill limit and practical minimums.

• Diametral Clearance (in) — computed as Bore ID − Shaft/Piston OD.

• Corner Radius Min / Max (in) — your inputs or the default range.

• Messages — the tool reports achieved gland fill (%) and flags out‑of‑range conditions.

4) Formulas used (transparent math)

• Diametral clearance

  clearance=Dbore−Dshaft\text{clearance} = D_\text{bore} – D_\text{shaft}clearance=Dbore​−Dshaft​

• Radial gland depth

  Dr=(1−s) C  −  clearance2D_r = (1 – s)\,C \;-\; \frac{\text{clearance}}{2}Dr​=(1−s)C−2clearance​

  where $s$ = squeeze fraction (e.g., 15% → 0.15)

• O‑ring cross‑sectional area (assumes circular section)

  Aring=π(C2)2A_\text{ring} = \pi \left(\frac{C}{2}\right)^2Aring​=π(2C​)2

• Groove width (meets fill limit and practical min)

  W  ≥  max⁡ ⁣(Aringg⋅Dr,  Wmin)W \;\ge\; \max\!\left(\frac{A_\text{ring}}{g \cdot D_r},\; W_\text{min}\right)W≥max(g⋅Dr​Aring​​,Wmin​)

  with $g$ = fill fraction (e.g., 85% → 0.85) and
  Wmin=1.10 CW_\text{min} = 1.10\,CWmin​=1.10C static, $1.25C$ dynamic.

• Achieved gland fill (tool displays this)

  fillachieved=AringW⋅Dr\text{fill}_\text{achieved} = \frac{A_\text{ring}}{W \cdot D_r}fillachieved​=W⋅Dr​Aring​​

• Corner radius defaults

  Rmin≈0.05 C,Rmax≈0.20 CR_\text{min} \approx 0.05\,C,\quad R_\text{max} \approx 0.20\,CRmin​≈0.05C,Rmax​≈0.20C

5) Quick procedure (step‑by‑step)

1. Select or type the cross‑section C.

2. Enter Bore ID and Shaft/Piston OD.

3. Choose Service (Static or Dynamic).

4. Enter Target Squeeze % and Max Gland Fill %.

5. (Optional) Enter Corner Radius Min/Max.

6. Click Calculate.

7. Review Dᵣ, W, clearance, and the achieved fill message.

8. If the tool flags issues, adjust:

   • Increase W (or reduce squeeze) if fill is too high.

   • Reduce clearance or increase C if Dᵣ ≤ 0.

   • For dynamic service, keep squeeze in the 8–16% band unless your spec says otherwise.

6) Worked example (static service)

Inputs

• Cross‑section $C=0.139$ in

• Bore ID Dbore=1.500D_\text{bore} = 1.500Dbore​=1.500 in

• Shaft/Piston OD Dshaft=1.490D_\text{shaft} = 1.490Dshaft​=1.490 in

• Target squeeze $s=15\%$

• Max gland fill $g=85\%$

Steps

1. Clearance $=1.500-1.490=0.010$ in.

2. Radial depth

Dr=(1−0.15)⋅0.139−0.0102=0.11815−0.005=0.11315 in (≈0.1132)D_r = (1 – 0.15)\cdot 0.139 – \frac{0.010}{2} = 0.11815 – 0.005 = 0.11315\ \text{in} \ (\approx 0.1132)Dr​=(1−0.15)⋅0.139−20.010​=0.11815−0.005=0.11315 in (≈0.1132)

3. O‑ring area

Aring=π(0.139/2)2=π(0.0695)2≈0.0151747 in2A_\text{ring} = \pi(0.139/2)^2 = \pi(0.0695)^2 \approx 0.0151747\ \text{in}^2Aring​=π(0.139/2)2=π(0.0695)2≈0.0151747 in2

4. Width by fill

Wby fill=0.01517470.85×0.11315≈0.15778 inW_{\text{by fill}} = \frac{0.0151747}{0.85 \times 0.11315} \approx 0.15778\ \text{in}Wby fill​=0.85×0.113150.0151747​≈0.15778 in

5. Practical minimum (static) Wmin=1.10⋅0.139=0.1529W_\text{min} = 1.10 \cdot 0.139 = 0.1529Wmin​=1.10⋅0.139=0.1529 in

6. Choose W = max(0.15778, 0.1529) = 0.15778 in

7. Achieved fill =AringW⋅Dr≈0.85= \frac{A_\text{ring}}{W \cdot D_r} \approx 0.85=W⋅Dr​Aring​​≈0.85 → 85% (meets limit)

Outputs

• Dᵣ ≈ 0.1132 in

• W ≈ 0.1578 in

• Clearance = 0.0100 in

• Rmin ≈ 0.05·C = 0.0070 in, Rmax ≈ 0.20·C = 0.0278 in

7) Design guidance (rules of thumb)

• Squeeze targets

  • Static: 10–30%.

  • Dynamic: 8–16%, aim low to reduce friction and heat.

• Gland fill

  • Keep ≤ 85% for general duty. Tight stacks, swell, and thermal growth need margin.

• Width minimums

  • Static: W ≥ 1.10·C.

  • Dynamic: W ≥ 1.25·C.

• Corner radii

  • Start with 0.05·C…0.20·C. Avoid sharp corners that cut the O‑ring.

• Clearance

  • Large clearance reduces Dᵣ and increases extrusion risk. At higher pressure, consider backup rings.

8) Interpreting messages

• “Calculated gland fill: … exceeds your limit.”
  Increase W or reduce squeeze.

• “Computed gland depth ≤ 0.”
  Clearance is too large for your combination of C and squeeze. Reduce clearance, increase C, or reduce squeeze.

• “Dynamic seals typically target ~8–16% squeeze.”
  Squeeze is outside the common dynamic band; verify with your spec.

9) Common pitfalls (and fixes)

• Bore ≤ Shaft/Piston → Enter the correct diameters; Bore must be larger.

• Over‑tight dynamic seal → Lower squeeze or increase width.

• High fill with small width → Increase W or reduce squeeze.

• Forgetting clearance impact → Clearance subtracts ½·clearance from Dᵣ. Large clearance can collapse the groove.

10) Assumptions & limits

• Cross‑section treated as circular; compression is uniform.

• No pressure‑based extrusion check in this MVP. Use backup rings and gap rules where required.

• No tolerance stack or thermal/swell model in this version. Allow margin.

• No O‑ring ID stretch or groove fit checks in this version.

11) Revision & support

• Tool: Groove Assistant — Phase 2 (Radial • Bore)

• Owner: M‑Cor, Inc.

• Use: Preliminary sizing aid. Verify against your internal standards and vendor handbooks before release.

Optional appendix — UI → variable map (for your team)

• C → gab_cs

• Bore ID → gab_bore

• Shaft/Piston OD → gab_shaft

• Service → gab_service

• Squeeze % → gab_squeeze

• Max Fill % → gab_fill

• Rmin / Rmax → gab_r_min / gab_r_max

• Outputs: gab_depth, gab_width, gab_clear, gab_rmin_out, gab_rmax_out