Comparison

HVAC Pipe Sizer vs SKF Shaft alignment

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

HVAC Pipe Sizer

This utility app helps engineers quickly size high-pressure gas piping systems. Input flow, pressure, and pipe properties to calculate diameters, velocity, and equivalent length. Supports English and metric units with built-in tables for various pipe materials.

Highlights
  • High-pressure gas pipe sizing
  • Input flow, pressure, and pipe parameters
  • Calculate exact/nominal diameters
  • Determine velocity and equivalent length
  • Supports English and metric units
  • Includes pipe fitting tables
  • Universal app for iPhone and iPad
Features
Read full description

The "HVAC Pipe Sizer - Gas High" application allows you to quickly size a simple high pressure (> 1.5psi) gas piping system by inputting a number of piping and gas properties. This is now a universal app that works on both the iPhone and iPad and sizes the screen size accordingly. You can specify the total gas flow in ft^3/hr (m^3/hr), the upstream pressure (psig or kPa), and one of either downstream pressure (psig or kPa), pipe internal diameter (inches) or gas velocity (ft/s) parameters. The results include both the exact and nominal pipe diameters and the calculated velocity and total pipe equivalent length. If you are analyzing an existing pipe system, there is an option to input the existing pipe internal diameter, the upstream pressure, and one of either downtream pressure or gas velocity parameters to derive the calculated gas flow and other remaining properties. You can specify additional parameters such as the type of gas, various properties of the gas, the pipe material type, the total length of pipe, quantities for up to 11 different types of pipe fittings, and much more. You can also choose to display values in either english or metric units. This application includes built-in pipe fitting equivalent length and nominal pipe sizing tables for a wide variety of pipe material types and diameters. This application uses slider controls that allow you to quickly increment or decrement the input values and immediately observe the calculated results. You can also manually input exact values. This application was designed by Carmel Software Corporation, a leader in HVAC design software since 1995. In fact, Autodesk (the makers of AutoCAD) acquired our load calculation software and incorporated it into their leading 3D modeling software called Revit. We also offer the following additional applications for the iPhone/iPad: 1. HVAC Duct Sizer 2. HVAC Pipe Sizer – Gas Low Pressure 3. HVAC Pipe Sizer - Gas High Pressure 4. HVAC Pipe Sizer – Liquid 5. HVAC Pipe Sizer – Steam 6. Steam Tables 7. Psychrometric Plus 8. Psychrometric LT 9. HVAC Pipe Sizer Plus 10. HVAC Pipe Sizer Gas Plus 11. HVAC Toolkit 12. HVAC Toolkit Ultimate 13. HVAC Residential Load Calcs 14. HVAC Load Plus 15. HVAC Equipment Locator 16. ASHRAE Duct Fitting Database 17. ASHRAE 62.1 Ventilation Load Calcs 18. HVAC Psych HD 19. HVAC ResLoad-J 20. HVAC Residential Load Calcs HD

About

SKF Shaft alignment

This utility app, when paired with specific hardware, enables precise and intuitive shaft alignment for rotating machinery. It offers a demonstration mode for experiencing the full process without the hardware and generates automatic, shareable reports.

Highlights
  • Intuitive shaft alignment with hardware
  • Flexible three-position measurement
  • Demonstration mode for full experience
  • Automatic, customizable alignment reports
  • Explanatory setup and measurement videos
  • 3D animations for guidance
  • Machine library with QR code scanner
Features
Read full description

The Horizontal shaft alignment app is designed to be used with the SKF Shaft Alignment Tool TKSA 51 or TKSA 71. Together, the hardware and the app form an alignment system that allows shaft alignments of many rotating machines to be made in an intuitive and easy way. The system uses line laser to PSD technology that enables highly accurate and reliable shaft alignments. The hardware and its app communicate wirelessly via Bluetooth®. Without the hardware the app can nonetheless be used, as it features a fully functional demonstration mode allowing the complete alignment process to be experienced before purchasing the TKSA 51 or TKSA 71 instrument.

 KEY FEATURES:
 • Very easy-to-use – The Horizontal shaft alignment app focuses on making the main alignment tasks as easy as possible and enabling accurate shaft alignments. 

• Full measurement flexibility – The Horizontal shaft alignment app uses a flexible three position measurement method that allows measurements to start at any angle and if the space is limited alignments can be performed with a total of 40° rotation only.

 • Demonstration mode – The Horizontal shaft alignment app offers a fully functional demonstration mode allowing the complete alignment process to be experienced before purchasing a supported SKF Shaft Alignment Tool.

 • Automatic alignment report – Automatically generated alignment reports give a complete overview of the alignment process and results. The reports can be customised with additional notes, a machine picture, a signature and can easily be shared via email or cloud services.

 • Explanatory videos – Easy to follow videos demonstrating how to set up and perform accurate measurements using the TKSA 51 or TKSA 71.

 • 3D Animations – 3D animations guide the user through the alignment process, allowing accurate shaft alignment to be performed in a very easy way.

 • Machine library and QR code scanner – Helps keeping track of the machines that have been measured. Machine information like distances, the machine picture, and other details are saved for each machine and can be reused the next time the same machine is measured. QR codes can be scanned to identify a machine and quickly retrieve its details. The library can also be used for easy access to all the reports generated for each machine in one place. HARDWARE – SKF Shaft Alignment Tool TKSA 51 and TKSA 71:
 The SKF TKSA 51 and TKSA 71 systems use a pair of measurement units that are combined with laser transmitter and detectors to measure and correct shaft alignment with high accuracy and reliability. The data is transferred in real time through Bluetooth® 4.0 LE to the app.

 IMPORTANT NOTE:
This app is designed to be used with the SKF Shaft Alignment Tool TKSA 51 or TKSA 71 hardware. 
The SKF TKSA 51 or TKSA 71 can be purchased separately from your local SKF Authorized Distributor. For more information and technical specifications about the SKF Shaft Alignment Tool, please visit our website.

Screenshots

HVAC Pipe Sizer4 screens
SKF Shaft alignment4 screens

Verdict

The call

The clearest difference is price: SKF Shaft alignment at Free against HVAC Pipe Sizer's $4.99. SKF Shaft alignment also leads on update cadence (every 3 months vs every 9 months) and ratings volume (10 vs 3). HVAC Pipe Sizer's advantage is rating (5.0 vs 3.7). On review sentiment, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

SKF Shaft alignment is free to download; HVAC Pipe Sizer costs $4.99 up front. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

HVAC Pipe Sizer holds the better App Store score, 5.0 against 3.7. Both are backed by a comparable volume of ratings — 3 and 10 respectively. Written reviews split almost evenly too, at 100% and 100% positive.

UpkeepUpdate frequency

HVAC Pipe Sizer ships an update every 9 months, SKF Shaft alignment every 3 months. The most recent releases landed on October 27, 2026 and October 29, 2026 respectively.

Scorecard5 real differences · 5 level
HVAC Pipe Sizer versus SKF Shaft alignment: the parameters behind the verdict, then further details
ParameterHVAC Pipe SizerSKF Shaft alignment
Price$4.99Free — better
Rating5.0 (3 ratings) — better3.7 (10 ratings)
Positive reviews100.0% of reviews100.0% of reviews
Number of ratings310 — better
Update frequencyEvery 9 monthsEvery 3 months — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaidFree — better
DevicesiPhone, iPadiPhone, iPad
Requires iOS17.016.0 — better
Further details — not scored
Size1 MB72 MB
Age rating4+4+
DeveloperCarmel Software CorporationSKF

Customer experience

HVAC Pipe Sizer

All ratings3 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews4 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

SKF Shaft alignment

All ratings10 ratings
Positive60.0%
Neutral20.0%
Negative20.0%
Written reviews2 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

HVAC Pipe Sizer

No in-app purchases

None

SKF Shaft alignment

No in-app purchases

Questions

Is HVAC Pipe Sizer free?
HVAC Pipe Sizer costs $4.99, with no in-app purchases.
Is SKF Shaft alignment free?
SKF Shaft alignment is free to download, with no in-app purchases.
Which has better reviews, HVAC Pipe Sizer or SKF Shaft alignment?
HVAC Pipe Sizer is rated higher. HVAC Pipe Sizer averages 5.0 out of 5 from 3 ratings, while SKF Shaft alignment averages 3.7 from 10 ratings.
Do HVAC Pipe Sizer or SKF Shaft alignment have ads?
Neither HVAC Pipe Sizer nor SKF Shaft alignment shows ads.
Which is updated more often, HVAC Pipe Sizer or SKF Shaft alignment?
HVAC Pipe Sizer ships an update every 9 months, and SKF Shaft alignment every 3 months. Most recently, HVAC Pipe Sizer was updated on October 27, 2026 and SKF Shaft alignment on October 29, 2026.

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