Neutrium.pipe

Create pipe, tube, fitting, and valve definitions for engineering applications. Calculate geometry with units, select dimensions from standard catalogues, and share physical component definitions across your piping model.

API reference · Interactive demo

Getting started

Requires Node.js 24 or newer. The package uses ES modules and includes TypeScript declarations. Browser applications need a bundler that resolves npm dependencies.

npm install @neutrium/pipe

Then:

import { Pipe } from '@neutrium/pipe';

const pipe = new Pipe('100mm', '6mm'); // Outer diameter and wall thickness

console.log(pipe.internalDiameter.to('mm').scalar.toNumber()); // 88
console.log(pipe.internalVolume('2m').to('L').scalar.toNumber()); // About 12.16
console.log(pipe.mass('2m', '7850kg/m3').to('kg').scalar.toNumber()); // About 27.82

Dimensions accept strings with units or Quantity objects from @neutrium/quantity. Results are Quantities, so you can convert units with to() and extract a JavaScript number with scalar.toNumber().

Using a pipe or tube

import {
    ASME_B36_10_Pipe,
    ASTM_B88_Tube,
    ASTM_B88M_Tube,
    ISO_11922_Pipe,
    BWG_Tube,
} from '@neutrium/pipe/pipes';

const steel = ASME_B36_10_Pipe.fromDN(100, '40');
const sameSteel = ASME_B36_10_Pipe.fromNPS(4, '40');
const copper = new ASTM_B88_Tube('1in', 'K');
const metricCopper = new ASTM_B88M_Tube('22mm', 'A');
const polyethylene = new ISO_11922_Pipe('200mm', '10', 'PE80');
const gaugeTube = new BWG_Tube('1in', '16');

| Class | Selection | Additional properties | | --- | --- | --- | | ASME_B36_10_Pipe | DN or NPS designation and schedule | dn, nps, schedule, nominalSize | | ASTM_B88_Tube | Nominal inch size and type K, L, or M | type, nominalSize | | ASTM_B88M_Tube | Metric designation and type A, B, or C | type, nominalSize | | ISO_11922_Pipe | Metric size, pressure rating string, and compound (PE100 by default) | pressureRating, compound, standardDimensionRatio, nominalSize | | BWG_Tube | Actual outer diameter and gauge string | gauge |

Nominal sizes are designations, not measured diameters: DN100 and NPS4 identify the same steel pipe. Prefer fromDN() and fromNPS() to make that choice explicit. They return dimensions in millimetres and inches respectively.

Select an exact supported designation; catalogue constructors reject unsupported sizes and combinations. Schedules accept strings or numbers, such as '40' or 40. Pressure ratings and gauges use strings, such as '10' and '16'.

The PE wall table covers AS/NZS 4130 Series 1 dimensions under the historical class name ISO_11922_Pipe. Catalogue availability describes the bundled data, not manufacturer stock or certification. See the catalogue data guide for reference sources and verification coverage.

Working with geometry

All pipe and tube classes expose the same geometry:

| Property | Meaning | | --- | --- | | outerDiameter | Actual outside diameter | | internalDiameter | Bore diameter | | wallThickness | Pipe wall thickness | | internalCrossSectionalArea | Bore area | | externalCrossSectionalArea | Area enclosed by the outer diameter | | materialCrossSectionalArea | Pipe wall area, excluding the bore |

Outer diameter and wall thickness retain their supplied units. Calculated internal diameter and areas use the outer diameter's units. Mixed input units are supported.

import { Pipe } from '@neutrium/pipe';
import { Quantity } from '@neutrium/quantity';

const pipe = new Pipe('100mm', new Quantity('0.6cm'));

pipe.internalDiameter.to('in');
pipe.materialCrossSectionalArea.to('cm2');
pipe.internalVolume('2m').to('L');
pipe.materialVolume('2m').to('m3');
pipe.internalSurfaceArea('2m').to('m2');
pipe.externalSurfaceArea('2m').to('m2');
pipe.mass('2m', '7850kg/m3').to('kg');

Pipe diameters and wall thickness must be finite, positive lengths, with wall thickness less than half the outer diameter. Segment lengths may be zero; material density must be finite and positive, with mass-per-volume units. Surface areas exclude end faces. Mass includes the pipe wall only.

Numeric snapshots

Use raw(unit) when passing geometry to calculations that use ordinary JavaScript numbers. Lengths use the requested unit; areas use its square. Omitting the unit uses the outer diameter's units.

const geometry = pipe.raw('m');

geometry.internalDiameter; // 0.088
geometry.outerDiameter;    // 0.1
geometry.wallThickness;    // 0.006
geometry.internalCrossSectionalArea; // m²

The snapshot contains all six geometry properties and is detached from the pipe. Editing it does not change the original definition.

Finding catalogue sizes

Use available*() methods to populate size and grade selectors:

import {
    ASME_B36_10_Pipe,
    ASTM_B88_Tube,
    ISO_11922_Pipe,
    BWG_Tube,
} from '@neutrium/pipe/pipes';

ASME_B36_10_Pipe.availableSizes('NPS', '40');
ASME_B36_10_Pipe.availableSchedules(100, 'DN');
ASTM_B88_Tube.availableTypes(0.25);
ISO_11922_Pipe.availablePressureRatings(200, 'PE80');
BWG_Tube.availableGauges('1in');

Each catalogue class also provides find(options). Results are pipe instances ordered by internal diameter, smallest first. minimumInternalDiameter is an inclusive lower bound; omit it to find all combinations matching the other filters.

const candidates = ASME_B36_10_Pipe.find({
    schedule: '40',
    minimumInternalDiameter: '100mm',
});

const smallest = candidates[0];
if (smallest) {
    console.log(smallest.dn, smallest.internalDiameter.to('mm').scalar.toNumber());
}

const polyethylene = ISO_11922_Pipe.find({
    compound: 'PE80',
    pressureRating: '10',
    minimumInternalDiameter: '150mm',
});

Well-formed filters with no matches return []. Malformed filters or incompatible units throw a structured error. Use the API reference for each catalogue's search options and discovery methods.

Fittings, valves, and connections

A component describes physical equipment with a kind and named ports. Use Port for a connection, or Port.fromPipe() to copy a pipe's actual dimensions. Pass a nominal designation explicitly when you want to retain it.

import { ASME_B36_10_Pipe } from '@neutrium/pipe/pipes';
import { Port } from '@neutrium/pipe/connections';
import { Elbow, Tee, Reducer } from '@neutrium/pipe/fittings';
import { Valve } from '@neutrium/pipe/valves';

const pipe = ASME_B36_10_Pipe.fromDN(100, '40');
const connection = Port.fromPipe(pipe, {
    nominalSize: pipe.nominalSize,
    connection: 'flanged',
});
const branch = new Port({ internalDiameter: '50mm' });

const elbow = new Elbow({ port: connection, angle: 90, bendRadius: '150mm' });
const tee = new Tee({ run: connection, branch });
const reducer = new Reducer({ inlet: connection, outlet: branch, style: 'concentric' });
const valve = new Valve({ valveType: 'ball', inlet: connection, boreDiameter: '80mm' });

console.log(elbow.ports.inlet.internalDiameter);

| Definition | Ports | Options | | --- | --- | --- | | Elbow | inlet, outlet | Angle in degrees (default 90), optional centreline bend radius | | Tee | run1, run2, branch | Branch angle in degrees (default 90); branch defaults to the run port | | Reducer | inlet, outlet | concentric or eccentric style, optional length; port bores must differ | | Valve | inlet, outlet | Valve type, optional bore diameter and face-to-face length; outlet defaults to inlet |

Connection and valve type identifiers are open strings. Unspecified dimensions remain undefined. Nominal sizes and connection labels alone do not establish mechanical compatibility.

Pipe definitions and component adapters

Use PipeComponent to expose a pipe through the same inlet/outlet interface as fittings and valves:

import { Pipe, PipeComponent } from '@neutrium/pipe/pipes';

const component = new PipeComponent(new Pipe('100mm', '5mm'));

component.ports.inlet.internalDiameter;
component.pipe.internalCrossSectionalArea;

Custom geometry can implement PipeDefinition, whose six geometry fields are readonly Quantities. Consumers can accept ComponentDefinition for equipment with a kind and named ports, without requiring inheritance from a library class.

Creating custom components

Extend TwoPortComponent for inline equipment or Component<YourPortMap> for other port arrangements. Use the public validation helpers for custom dimensions.

import { Quantity } from '@neutrium/quantity';
import { TwoPortComponent } from '@neutrium/pipe/components';
import type { PortDefinition } from '@neutrium/pipe/connections';
import { positiveLength } from '@neutrium/pipe/validation';

class Strainer extends TwoPortComponent {
    readonly meshSize: Quantity;

    constructor(port: PortDefinition, meshSize: string | Quantity) {
        const validatedMeshSize = positiveLength(meshSize, 'meshSize', 'Mesh size');
        super({ kind: 'strainer', inlet: port });
        this.meshSize = validatedMeshSize;
    }
}

Validate custom options before calling super(), because successful component construction freezes the supplied port definitions. Custom subclasses are responsible for protecting their own additional fields.

Handling invalid input

Use isPipeError() to recognise library validation errors and inspect code, field, value, and allowedValues. Parser failures also retain cause.

import { ASME_B36_10_Pipe, isPipeError } from '@neutrium/pipe';

try {
    ASME_B36_10_Pipe.fromDN(100, 'unknown');
} catch (error: unknown) {
    if (isPipeError(error)) {
        console.log(error.code, error.field);
        console.log(error.allowedValues);
    } else {
        throw error;
    }
}

| Error | Meaning | | --- | --- | | PipeTypeError | Wrong input type, malformed value, or incompatible units | | PipeRangeError | Non-finite or out-of-range number, or impossible geometry | | PipeError | Well-formed but unsupported selection |

Optional defaults apply to omitted values or undefined; null is rejected. Use error codes and fields for programmatic handling instead of matching messages.

Public validation helpers

Import positiveLength, nonNegativeLength, finiteNumber, lengthQuantity, and densityQuantity from @neutrium/pipe/validation for custom components. Length and density helpers parse strings or Quantities; finiteNumber checks a JavaScript number without coercion. The helpers throw the same structured errors as the built-in classes.

Public entry points

Import from @neutrium/pipe for the complete API, or choose a focused feature path:

| Entry point | Use | | --- | --- | | @neutrium/pipe/pipes | Pipe and tube classes, catalogue searches, PipeComponent, PipeDefinition, RawPipe | | @neutrium/pipe/connections | Port, connection options, PortDefinition, NominalSize | | @neutrium/pipe/components | Component base classes, component contracts, metadata types | | @neutrium/pipe/fittings | Elbow, Tee, Reducer, and their options | | @neutrium/pipe/valves | Valve and its options | | @neutrium/pipe/validation | Dimension and number validation helpers | | @neutrium/pipe/errors | Error classes, error types, and isPipeError |

Import types from their owning feature path or the root:

import { Valve, type ValveOptions } from '@neutrium/pipe/valves';
import type { PortDefinition } from '@neutrium/pipe/connections';

Guides and reference

• API reference: constructors, properties, options, and types.
• Interactive demo: explore catalogue dimensions and geometry.
• Catalogue data: dimensional sources and verification coverage.
• Migrating to version 3.
• Migrating to version 2.
• Development and releases: tests, benchmarks, documentation builds, and publishing.

License

Overview

This project is licensed under the MIT License, see the LICENCE file for details.

You are free to:

• Use this plugin for personal or commercial purposes
• Modify and distribute the code
• Include it in other projects

Under the following conditions:

• You must include the original license and copyright notice

Disclaimer

This library is provided "as is", without warranty of any kind. Use at your own risk.