Can tapered threads PT and pipe threads G be used together?

On Baidu: There are two types of fits for imperial sealed pipe threads: “column/taper” and “taper/taper”. The two British imperial sealed pipe threads use different thread gauges (cylindrical thread gauges and tapered thread gauges) as well as thread plug gauges; the positions of their reference planes differ, with the two reference planes being separated by half a thread pitch. Europe **primarily uses columns/cones in combination with threads** ； Outside of Europe, **“taper/taper” threaded connections are primarily used.** For the same sealed pipe thread fitting, pipe threads that pass inspection in Europe may fail inspection outside of Europe. In international trade, it is essential to pay attention to such differences; otherwise, defective products may arise. Before 1994, ISO’s standards for British sealing pipe threads and their gauges were designed based on a \"taper/taper\" fit system. China’s British-style sealed pipe thread products can enter the international market directly. Meanwhile, the threaded pipe products in Europe are at a disadvantage. After 2000, ISO’s British standard for sealed pipe threads and its gauge standards were designed based on the \"column/cone\" fit system. China’s existing British-standard sealed pipe thread products face difficulties when entering the international market. To this end, our country revised the British standard for sealed pipe threads in 2000. Changing the original single thread standard to two thread standards serves as a reminder for designers to pay attention to the differences between the two types of mating threads and to select them appropriately. When Japan revised its British standard for sealed pipe threads in 1999, it continued to adhere to the ISO standards from before 1994. Therefore, the international market for British imperial sealing pipe threads after 2000 has become more complex, and domestic manufacturers need to be especially cautious. http://baike.baidu.com/link?url=slS8Wuu7kYBqraOdVVvM2gpDPn-Lla1G3oeTIwtqJOJ1ExGPNMMzSlscC418vl34yI39ay5Pkhw78CxYv295S_

I want to ask this question too. Is there an answer?

Posting messages in such a slow, tedious manner – if you do this again, I’ll drag you outside and beat you to death. ;P You can take a look at the information – NPT tapered threads and G straight threads; it’s already good if 2 turns can be achieved when tightening them. How should they be used together? If you have low pressure, it doesn’t matter if there’s a leak; in cases like with fresh water or air, you can use external force to damage the threads and join them together, which will provide temporary protection. But in the future, it won’t be possible to repair it.

NPT threads definitely cannot be matched with G threads.

It’s PT, 55°. It’s not NPT; this one is 60°. Is that okay?

A PT external thread can be screwed into a G internal thread, but an external thread cannot be screwed into a PT internal thread. It is best to match it with threads.

It works fine only when they are connected, but it’s not acceptable if pressure sealing is required; leakage will occur if the mating surfaces of the two parts do not fit properly