What are NPT Fittings?

Image description: A NPT fitting

With competitive price and timely delivery, JIANZHI sincerely hope to be your supplier and partner.

NPT or national pipe, or National Pipe Tapered, is an American standard defined under the AMSE B1.20.1. The standard outlines the dimensions and tolerances of tapered threads for pipes and fittings. Unlike straight threads, tapered threads give a more reliable seal, especially when used with a sealant material like Teflon tape. The standard is more than a hundred years old and was initially defined for plumbing applications; however, it has seen effective use in hydraulic and gas conveyance as well.

Characteristics of NPT Threads

NPT threads are defined by the following features:

• The taper angle is 1

  O

  47&#; (measured from the center axis of the NPT fitting)
• Flat crests and troughs
• 60

  O

  angle between each crest and trough
• The outer diameter of an NPT fitting is measured at the midpoint of the taper
• Pitch (the distance between threads) is measured in threads per inch (TPI)

Sizing in NPT threads

NPT defines both internal and external threads on fittings that conform to the standard; hence sizing charts give diameter measurements for both male and female parts. As a result, all male and female fitting types have consistency, adhering to the same taper rate &#; change in thread diameter per unit length. For the NPT standard, the taper rate is ¾ inch per foot or 1/16 inch per inch.

Since the O.D. is measured from the midpoint, confusion may arise when selecting the correct size fitting. An NPT fitting labeled as 1/8&#; has an actual outer diameter of 3/8&#;. So be careful when selecting NPT fittings, as you may end up using a fitting that&#;s too loose. The chart below summarizes the dimensions of some commonly used sizes. Note that some NPT fitting sizes have the same TPI; hence they can be used on each other on account of the taper.

Advantages of Using NPT Thread Fittings

Given that the standard has been around for a while, it has a set of advantages when being used. It is readily available in vendor inventories, with multiple sizes and materials to choose from. This allows you to use them for many applications at varying pressures. Moreover, they can be assembled in a simple manner as the metal-to-metal contact offers an excellent seal.

Disadvantages of Using NPT Thread Fittings

The metal-to-metal contact in NPT fittings relies on the deformation of the threads to form a secure seal. This, however, means that one cannot use them in applications that require frequent disassembly.

If used improperly, that is, without correct alignment, overtightening, or wrong sizing, ports may expand, and cracks may form on the threads. This, in turn, leads to the formation of leakage pathways from where the medium can leak out. It is for this reason that NPT fittings are not recommended for extremely high-pressure applications.

Want more information on npt threading? Feel free to contact us.

Privacy Policy

This privacy policy sets out how we uses and protects any information that you give us when you use this website.

We are committed to ensuring that your privacy is protected. Should we ask you to provide certain information by which you can be identified when using this website, then you can be assured that it will only be used in accordance with this privacy statement.

We may change this policy from time to time by updating this page. You should check this page from time to time to ensure that you are happy with any changes.

What we collect

We may collect the following information:

• name and job title
• contact information including address
• demographic information such as postcode, preferences and interests
• other information relevant to customer surveys and/or offers

What we do with the information we gather

We require this information to understand your needs and provide you with a better service, and in particular for the following reasons:

• Internal record keeping.
• We may use the information to improve our products and services.
• We may periodically send promotional emails about new products, special offers or other information which we think you may find interesting using the address which you have provided.

Security

We are committed to ensuring that your information is secure. In order to prevent unauthorised access or disclosure, we have put in place suitable physical, electronic and managerial procedures to safeguard and secure the information we collect online.

How we use cookies

A cookie is a small file which asks permission to be placed on your computer's hard drive. Once you agree, the file is added and the cookie helps analyse web traffic or lets you know when you visit a particular site. Cookies allow web applications to respond to you as an individual. The web application can tailor its operations to your needs, likes and dislikes by gathering and remembering information about your preferences.

We use traffic log cookies to identify which pages are being used. This helps us analyse data about webpage traffic and improve our website in order to tailor it to customer needs. We only use this information for statistical analysis purposes and then the data is removed from the system.
Overall, cookies help us provide you with a better website by enabling us to monitor which pages you find useful and which you do not. A cookie in no way gives us access to your computer or any information about you, other than the data you choose to share with us.
You can choose to accept or decline cookies. Most web browsers automatically accept cookies, but you can usually modify your browser setting to decline cookies if you prefer. This may prevent you from taking full advantage of the website.

Links to other websites

Our website may contain links to other websites of interest. However, once you have used these links to leave our site, you should note that we do not have any control over that other website. Therefore, we cannot be responsible for the protection and privacy of any information which you provide whilst visiting such sites and such sites are not governed by this privacy statement. You should exercise caution and look at the privacy statement applicable to the website in question.

Controlling your personal information

You may choose to restrict the collection or use of your personal information in the following ways:

• whenever you are asked to fill in a form on the website, look for the box that you can click to indicate that you do not want the information to be used by anybody for direct marketing purposes
• if you have previously agreed to us using your personal information for direct marketing purposes, you may change your mind at any time by writing to or emailing us.

We will not sell, distribute or lease your personal information to third parties unless we have your permission or are required by law to do so. We may use your personal information to send you promotional information about third parties which we think you may find interesting if you tell us that you wish this to happen.

If you believe that any information we are holding on you is incorrect or incomplete, please write to or us as soon as possible at the above address. We will promptly correct any information found to be incorrect.

Contact us to discuss your requirements of pipe fitting system. Our experienced sales team can help you identify the options that best suit your needs.