What are the common pipe thread types?

The thread of the drill pipe

Common drill pipe thread types are IF, FH, REG, hole FH, XH, which is not common in the tool shop and is not commonly used,commonly used IF and normal REG.

1.It is represented by three numbers, such as 310,410,411, etc.

2.The first number indicates the size (generally 2 ~ 7):2– 2-7/8 “; 3-3-1/2 “; 4-4-1/2 “; 5-5-1/2 “; 6-6-5/8 “; 7– 7-5/8 “;

3.The second number indicates the thread type (there are 1, 2, 3), 1– IF; 2—FH;  3– REG;

4.The third number represents male and female (represented by 0 and 1) 0– female thread; 1– public thread;

4. Other common drill pipe thread types are BTC, MT, AMT, HT55 and so on.

The thread of the Tubing

Common tubing thread types include EU and NU, while rare ones include NEW VAM and FOX.

1. The difference between EU and NU is as follows: EU is thickened with 8 thread per inch; NU is 10 thread per inch.

2. NEW VAM is used in gas Wells with good gas tightness.

3. If there is no EU or NU above 4-1/2 “, it is LTC and STC. The effective distance of LTC thread is long, while the effective distance of STC thread is short, both are round thread.

4. P is used for male thread and B is used for female thread.

5. EU thread common sizes are 2-3/8 “, 2-7/8 “, 2-7/8 “, 3-1/2 “, 4 “and 4-1/2″ and so on.

Common sizes of NU thread are 1.9 “, 2-3/8 “, 2-7/8 “, 3-1/2 “, and 4-1/2 “.

Common sizes for NEW VAM are 2-7/8 “and 3-1/2″.

Common sizes of FOX are 2-7/8 “, etc. 

The thread of the flush pipe

Common flush thread types are the HYDRILL CS, HYDRILL 511, TSWP, and FL-4S available in 2-7/8 “and 4″.

1. HYDRILL CS is 1.9 “and externally thickened, HYDRILL 511 is 2-7/8″ and thin to thick, TSWP is 4 “and sealed for double shoulders.

2. FL-CS for 2-7/8 “and 4″ flush thread shared.

There are three common thread types:

BTC, for the side ladder thread, the common size is 5-1/2 “, 6-5/8 “, 7 “and so on.

STC, for short round grain, common sizes are 4-1/2 “, 5-1/2 “, 6-5/8 “, 7 “, 7-5/8 “and so on.

LTC is a long thread, the common sizes are 4 “, 4-1/2 “, 5-1/2 “, 7 “and so on.

Special thread

1. Special thread for sealing unit:ACME thread type, common sizes are 3.25 “, 4 “(3-5/8″), 4.75 “, 6 “.

2.LP thread type: triangular in section, is somewhat similar to the EU, but it has a sharp feeling to the touch,LP thread is commonly used in high pressure manifold, common sizes are 2 “and 3″.

3.By non-thread:Common ones are 1502 and 1602.

4. Milling tube:FJWP