PIPE SPOOL TAKEOFF SOFTWARE

Pipe Spool Takeoff Software
for Welders & Fab Shops

Generate cut lists with ASME B36.10 pipe weights, fittings BOM, and flange schedule for ASME B31.1, B31.3, B31.9, and API 1104 projects — in seconds, not hours. Free demo, no signup.

Try the free takeoff tool → See IronKit plans

What Is a Pipe Spool Takeoff?

A pipe spool takeoff is the process of calculating the exact quantities and weights of every material component in a fabricated pipe assembly — the cut pipe length by NPS and schedule, fittings count by type and size, and flanges by type and class. The takeoff is what you hand to the shop foreman and use to price the job.

A sloppy takeoff is the fastest way to lose margin. Missing a 6" weld-neck Class 300 flange might cost you $80–$150 in material you didn't price. Multiply that across a 20-spool job and you've eaten half your profit before you strike an arc.

Most small-to-mid pipe fabrication shops do takeoffs one of three ways: hand-counting from paper isometrics (~45 minutes per spool), Excel spreadsheets (faster but error-prone), or expensive enterprise CAD/piping software ($5,000–$50,000/year). IronKit fills the gap between a legal pad and a $50K software seat.

What IronKit generates in seconds: ASME B36.10M pipe weight (lb/ft and total), OD and wall thickness by NPS/schedule, fittings BOM with estimated weight by type, flange BOM by class, total spool weight in lb and tons, and an AI-generated shop report with code-specific fabrication notes.

How IronKit Calculates Pipe Weight

Pipe weight is computed using the ASME B36.10M standard formula:

lb/ft = 10.69 × (OD − Wall Thickness) × Wall Thickness

OD and wall thickness values are pulled from ASME B36.10M (carbon and alloy steel) and B36.19M (stainless steel) tables by NPS (1/2" through 12") and schedule (Sch 5 through Sch XXS, plus STD and XS designations).

Fitting and flange weights use industry rule-of-thumb estimation by pipe size, type, and flange class — field-tested values for shop estimating, not certified mill weights. Accurate to ±10–15% for a fabricated assembly, which is well within bid estimation tolerances.

Sample Pipe Spool BOM — ASME B31.3 Process Piping

Example output for a 6" NPS Sch 40 Carbon Steel spool — 48 LF, 2 ea 90° elbows, 1 ea tee, 4 ea weld-neck Class 300 flanges:

◆ Spool SP-01 — 6" Sch 40 CS — ASME B31.3 Process
Pipe spec6" NPS Sch 40 CS | OD 6.625" | WT 0.280"
Pipe weight rate18.97 lb/ft
Cut length48 LF
Pipe weight910 lb
2 ea 90° elbow 6"~38 lb
1 ea tee 6"~57 lb
4 ea WN flange 6" Class 300~132 lb
Spool total weight1,137 lb

Manual Takeoff vs. IronKit — Time and Accuracy

MethodTime per SpoolAccuracyWeight CalcCode NotesCost
Hand count (paper iso) 30–90 min Error-prone Manual lookup None Free but slow
Excel spreadsheet 15–30 min OK Manual formula None Free but fragile
Enterprise CAD piping software Fast (from iso) High Certified Yes $5K–$50K/yr
IronKit < 2 min ±10–15% ASME B36.10M B31.1, B31.3, B31.9, API 1104 $29/month (all 20 tools)

Supported Design Codes & Materials

Pipe materials: Carbon Steel, Stainless 304 SS, Stainless 316 SS, Chrome-Moly P11 (1¼ Cr – ½ Mo), Chrome-Moly P22 (2¼ Cr – 1 Mo), Duplex 2205. NPS ½" through 12".

Fitting types: 90° elbow, 45° elbow, tee, reducer, cap, coupling, union, cross, return bend.

Flange types: weld-neck, slip-on, socket-weld, blind, threaded, lap-joint. ASME B16.5 classes 150# through 2500#.

Frequently Asked Questions

What is a pipe spool takeoff and why does it matter?
A pipe spool takeoff calculates exact cut lengths, fittings quantities, flange counts, and material weights from a piping isometric or P&ID. An accurate takeoff is the foundation of a competitive bid — miss a fitting and you eat the cost. Most small shops still do this by hand in 30–90 minutes per spool. IronKit does it in under 2 minutes with ASME B36.10M weights.
How does IronKit calculate pipe weight?
Using the ASME B36.10M formula: lb/ft = 10.69 × (OD − WT) × WT. OD and wall thickness are looked up from ASME B36.10M (carbon/alloy steel) and B36.19M (stainless) tables by NPS and schedule. Fitting and flange weights use industry estimation factors by pipe size, type, and class — accurate to ±10–15% for shop estimating.
What design codes does IronKit support?
ASME B31.1 (Power Piping), ASME B31.3 (Process Piping), ASME B31.9 (Building Services), and API 1104 (Pipeline Welding). The AI fabrication notes include code-specific guidance on NDE scope, purging requirements, preheat, and hydrotest pressure (1.5× design pressure per the applicable code).
What is the difference between ASME B31.1 and B31.3?
B31.1 governs Power Piping — steam, feedwater, blowdown piping in power plants and industrial boilers. B31.3 governs Process Piping — petroleum refining, chemical processing, pharma, and semiconductor piping. B31.3 has stricter NDE requirements for Category M (lethal service) and requires 100% RT for certain P-numbers and thicknesses. Check the project specification or consult the client's piping engineer if you're unsure which code applies.
Can this handle stainless and chrome-moly pipe?
Yes. IronKit supports SS 304, SS 316, P11 (1¼Cr–½Mo), P22 (2¼Cr–1Mo), and Duplex 2205. Weights are computed from ASME B36.19M for stainless. The AI notes include material-specific guidance — P11/P22 preheat requirements, stainless purging for root pass, and duplex heat input control.
How do pipe fab shops currently do takeoffs without software?
Three ways: hand-count from paper isometrics (30–90 min/spool), Excel spreadsheets (faster but fragile), or enterprise CAD piping software (ISOGEN, SmartPlant — $5K–$50K/yr). IronKit fills the gap: professional-grade takeoffs at $29/month, no CAD files required.

Run your first pipe spool takeoff now

Free demo — no signup. Enter NPS, schedule, cut length, fittings, and flanges. Get ASME B36.10 weights and a full BOM in under 2 minutes.

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