Do you know the difference and advantage for NPT and NPTF threads of adapters and fittings

NPT and NPTF threads are threads used on hydraulic adapters and fittings, and they have significant differences and advantages. This article will provide a detailed introduction to their similarities, differences, and respective advantages.

1. Similarities

NPT and NPTF threads are both tapered threads with a thread angle of 60 degrees. Besides, there are many similarities between them.

Firstly, they all use American national standards, which are the most commonly used thread types on pipes and fittings. Secondly, they all require the use of strict precision dimensions and machining techniques to complete. Meanwhile, they all have good sealing performance and can be applied in high-pressure, high-temperature, and high-density pipeline systems.

2. Differences

Although NPT and NPTF threads are similar, there are still significant differences between them.

Firstly, NPT threads have an opening at the top of the thread to facilitate the discharge of air, making them more common in hydraulic and gas pipeline applications. NPTF threads, on the other hand, do not have such openings and have superior sealing performance, making them more commonly used in hydraulic pressure applications.

Secondly, the thread depth of the two is different. The pitch of NPT teeth is 3.175mm, the depth of thread teeth is 1.59mm, while the pitch of NPTF teeth is also 3.175mm, and the depth of thread teeth is only 1.27mm. If used in pairs, NPT threads will put higher pressure on NPTF threads and cause poor sealing, which may lead to air and liquid leakage. In addition, due to the different depths of thread threads, it is necessary to be careful not to mix them when using long threaded socket joints.

Finally, the angles of the two are also different. The angle of NPT thread is 1.7899 degrees, and the angle of NPTF thread is 1.47 degrees. These small differences mean they have different functions and application areas.

3. Advantages

NPT and NPTF threads each have unique advantages. Here are their advantages:

(1) Advantages of NPT threads:

① Easy to operate: The opening of the NPT thread can bring great convenience to the operator in terms of exhaust, which makes it very popular in industrial and construction applications.

② Better pressure management: NPT threads can demonstrate better performance in high-pressure and gas pipeline applications, which is also one of the reasons why they are widely used in the industrial field.

(2) Advantages of NPTF threads:

① Better sealing: NPTF threads have no openings and have better sealing performance, making them more efficient than NPT threads. This makes it widely used in hydraulic pipeline systems.

② Higher compressive strength: Due to the shallower tooth depth of NPTF threads, their performance is excellent when subjected to greater pressure, and they can withstand higher pressure in hydraulic pressure without breaking.

In summary, NPT and NPTF threads each have their own advantages and useful functions, and choosing the most suitable thread to meet the needs of different applications is crucial. You can determine which type of thread to use to achieve the best effect based on actual usage and requirements.

NPT thread and NPTF thread are very common pipeline connection methods, which have the advantages of simple installation and disassembly, reliable sealing, and have been widely used in various industries.

4.The application of NPT and NPTF thread adapter and fitting.

NPT thread is a type of National Standard Thread American thread, which is a conical thread commonly used for transmitting gases, fluids, and other media. The main characteristics of NPT threads are good fastening, good sealing, and simple and convenient connection. Its installation process is also very simple, without the need for any sealing materials, as long as it is firmly screwed on to complete the connection. This type of hydraulic adapter is mainly suitable for pipeline systems under low pressure and normal temperature, such as water supply pipelines, oil pipelines, etc. Meanwhile, in hydraulic systems, due to its reliable sealing performance, NPT threads are also widely used on components such as hydraulic ball valves and oil pipe joints.

NPTF thread is also a type of tapered thread, commonly known as Fuel (NPF), which is tighter and provides better sealing than NPT thread. Its manufacturing accuracy and surface quality are also higher than NPT. Unlike NPT, NPTF has a smaller pitch and a larger thread angle of 60 degrees, while NPT generally has a thread angle of 55 degrees. NPTF hydraulic adapter are also suitable for low-pressure and ambient temperature pipeline systems, mainly used for transmitting media such as fuel and hydraulic oil. There are special wear-resistant plastic rings on the threads, which have better sealing effects than NPT threads. Therefore, in systems with high sealing requirements, NPTF threads are more widely used, such as in pneumatic components, oil pipe Fitting , and other components.