Design Tools

ARIavCAD | Icons for Designers & Engineers | A.R.I. Flange Table | Useful Technical Information

 

ARIavCAD: User-friendly air valve selection software that improves system efficiency and saves costs.

ARIavCAD is the latest and most advanced air valve sizing and location program available on the market, now in a convenient web-based format. It is an essential tool for all liquid system designers in designing safe and efficient liquid conveyance systems. Make confident and professional decisions, based on effective air valve performance data. The air valve modeling database is based on effective air valve flow rate results measured and tested in the A.R.I. advanced In-House Air Lab and designed and built according to EN1074-4.

ARIavCAD offers the following analysis types, for full pipeline protection:

Fill Rate Analysis, Safe Pipeline Filling, Drainage Analysis, Rupture Analysis, Burst Analysis, Water Column Separation Analysis, Maximum Spacing Distance Analysis, Energy Saving Analysis.

Design engineers will get customized air valve solutions for their specific application, whether that be Agriculture, Municipal (clean or wastewater systems), Industrial, or Mining applications.

Collaborate with your team via the web
The new ARIavCAD is web-based, which makes design collaboration between you and your team completely seamless. 

Reduce purchasing costs with smart selection
ARIavCAD works to maximize your return on investment by selecting the most cost-efficient air valve model, specific to your industry.

Easy data upload and user-friendly interface
Simply upload the pipe cross-section information (from a CSV or AutoCAD file) and pump curve data. Next, fine tune the information, then run the report to get air valve recommendations from A.R.I.’s wide range of air valve products, by location, model, size, and quantity.

Benefit from the expertise of the A.R.I. team
Once you’ve uploaded your data, the A.R.I. team will be there to guide you through the valve selection process – using their specialist expertise and vast experience to ensure that you get the best overall solution.

Energy Analysis
As an optional extra service, the A.R.I. engineering team can perform an Energy Analysis for your system, saving you significant energy costs over the lifecycle of your system.

 Click here to register to ARIavCAD: https://www.ariavcad.com/

Icons for Designers & Engineers

AutoCAD Icon Blocks of Air Valves

Download AutoCAD Icon Blocks of Air Valves

AutoCAD Icon Blocks of Check Valves

Download AutoCAD Icon Blocks of Check Valves

A.R.I. Flange Standard Table Third edition

Download ARI Flange Standard Table file

Useful Technical Information

NPS (Nominal Pipe Size)

Nominal Pipe Size (NPS) is a set of standard pipe sizes used for pressure piping in North America. The same pipe dimensions are used with different names in Europe.

Pipe size is specified with two non-dimensional numbers: a Nominal Pipe Size (NPS) and a schedule (SCH). The relationship of these numbers to the actual pipe dimensions is a bit strange. The NPS is very loosely related to the inside diameter in inches, but only for NPS 1/8 to NPS 12. For NPS 14 and larger, the NPS is equal to the outside diameter (OD) in inches. For a given NPS, the OD stays constant and the wall thickness increases with larger SCH. For a given SCH, the OD increases with increasing NPS while the wall thickness increases or stays constant. Pipe sizes are documented by a number of standards, including API 5L, ANSI/ASME B36.10M in the US, BS 1600 and BS EN 10255 in the United Kingdom and Europe, and ISO 65 internationally. 

For NPS of 5 and larger, the DN is equal to the NPS multiplied by 25 (not 25.4).

The most commonly used schedules today are 40, 80, and 160. There is a commonly held belief that the schedule number is an indicator of the service pressure that the pipe can take. For example, the McGraw Hill Piping Handbook says the schedule number can be converted to pressure by dividing the schedule by 1000 and multiplying by the allowable stress of the material. However, this is not true Pressure rating actually goes down with increasing NPS and constant schedule.

The various standards for pipe schedule are not identical. Frequently some sizes—or even entire schedules—are present in some standards but not others. When different standards do overlap, they usually have the same dimensions. For this reason, the source of the schedules is not distinguished in the table below. Beyond NPS 8, however, there are differing version of schedules 5, 10, 40, and 80. One variation is the presence or absence of an 'S' suffix after the schedule number. Generally, 'S' indicates Stainless Steel Schedule.

Some specifications use pipe schedules called Standard Wall (STD), Extra Strong (XS), and Double Extra Strong (XXS), although these actually belong to an older system called Iron Pipe Size (IPS). The IPS number is the same as the NPS number. 

STD is identical to SCH 40S, and 40S is identical to 40 for NPS 1/8 to NPS 10, inclusive. XS is identical to SCH 80S, and 80S is identical to 80 for NPS 1/8 to NPS 8, inclusive. Different definitions exist for XXS, but it is generally thicker than schedule 160.

8 to NPS 3-1/2

NPS 4 to NPS 8

NPS 10 to NPS 24

NPS 10 to NPS 24 (Continue)

Download NPS file

NPT (National Pipe Thread)

National Pipe Thread is a U.S. standard for tapered (NPT) or straight (NPS) threads used to join pipes and fittings. ANSI/ASME standard B1.20.1 covers threads of 60-degree form with flat crests and roots in sizes from ¹⁄16 inch to 24 inch Nominal Pipe Size. The taper rate for all NPT threads is ¹⁄16 (³⁄₄inch per foot) measured by the change of diameter (of the pipe thread) over distance. The taper divided by a center line yields an angle 1° 47' 24" or 1.7899° as measured from the center axis.

Commonly-used sizes are ¹⁄8, ¹⁄4, ³⁄8, ¹⁄2, ³⁄4, 1, 1 ¹⁄4, 1 ¹⁄2, and 2 inch, appearing on pipe and fittings by most U.S. suppliers. Smaller sizes than those listed are occasionally used for compressed air. Larger sizes are used less frequently because other methods of joining are more practical at 3 inches and above in most applications.

Nominal Pipe Size is loosely related to the inside diameter of schedule 40 pipe. Because of the pipe wall thickness, the actual diameter of the threads is larger than the NPS, considerably so for small NPS. Other schedules of pipe have different wall thickness but the OD (outer diameter) and thread profile remain the same, so the inside diameter of the pipe is therefore different from the nominal diameter.

Threaded pipes can provide an effective seal for pipes transporting liquids, gases, steam, and hydraulic fluid. These threads are now used in materials other than steel and brass, including PVC, nylon, bronze and cast iron.

The taper on NPT threads allows them to form a seal when torqued as the flanks of the threads compress against each other, as opposed to straight thread fittings or compression fittings in which the threads merely hold the pieces together and do not provide the seal. However a clearance remains between the crests and roots of the threads, resulting in a leakage around this spiral. This means that NPT fittings must be made leak free with the aid of thread seal tape or a thread sealant compound. (The use of tape or sealant will also help to limit corrosion on the threads, which can make future disassembly nearly impossible.)

There is also a semi-compatible variant called NPTF or Dryseal, designed to provide a more leak-free seal without the use of teflon tape or other sealant compound. NPTF threads are the same basic shape but with crest and root heights adjusted for an interference fit, eliminating the spiral leakage path.

Sometimes NPT threads are referred to as MPT (Male Pipe Thread), MNPT, or NPT(M) for male (external) threads and FPT (Female Pipe Thread), FNPT, or NPT(F) for female (internal) threads. An equivalent designation is MIP (Male iron pipe) and FIP (Female iron pipe).

Pipe thread sizes

 Download NPT file

BSPT (British Standard Pipe Thread)

The British standard pipe thread (BSP thread) is a family of standard screw thread types that has been adopted internationally for interconnecting and sealing pipe ends by mating an external (male) with an internal (female) thread.

Types

Two types of threads are distinguished:

• Parallel threads, which have a constant diameter.(G)

• Taper threads, whose diameter increases or decreases along the length of the thread.(R)

They can be combined into two types of joints:

• Jointing threads: These are pipe threads for joints made pressure-tight by the mating of the threads. They always use a taper external thread, but can have either parallel or taper internal threads. (In Continental Europe, taper internal pipe threads are not commonly used.)

• Longscrew threads: These are parallel pipe threads used where a pressure-tight joint is achieved by the compression of a soft material (gasket) on to the surface of the external thread by tightening a backnut against a socket.

Threadform

For both the taper and the parallel pipe threads, the Whitworth thread form is used, which has the following characteristics:

• symmetrical V-thread in which the angle between the flanks is 55° (measured in an axial plane)

• one-sixth of this sharp V is truncated at the top and the bottom

• the threads are rounded equally at crests and roots by circular arclend tangentially with the flanks

• the theoretical depth of the thread is therefore 0.64times the nominal pitch the relation between

Pipe thread sizes

A list of 15 thread sizes are defined by the standards, ranging from 1/16 to 6. The size number was originally based on the inner diameter measured in inches (25.4 mm) of a steel tube for which the thread was intended, but is in the modern metric version of the standard simply a size number.

The major diameter listed is the outer diameter of the external thread. For a taper thread, it is the diameter at the "gauge length" from the small end of the thread. The taper is "1 to 16", meaning that for each 16 mm increase in the distance from the end, the diameter increases by 1 mm.

Pipe thread designations

These standard pipe threads are formally referred to by the following sequence of blocks:

• the words "Pipe thread"

• the document number of the standard (e.g., "ISO 7" or "EN 10226")

• the symbol for the pipe thread type:

  • G = external+internal parallel (ISO 228)

  • R = external taper (ISO 7)

  • Rp = internal parallel (ISO 7)

  • Rc = internal taper (ISO 7)

• the thread size

Threads are normally right-hand. For left-hand threads, the letters "LH" are appended.
Example: Pipe thread EN 10226 Rp 2 1/2

Download BSPT file

Dimensions

The above is free as a courtesy - accuracy is not guaranteed.

Download Dimensions file