鉆桿浮閥一般連接在鉆頭之上，主要用來防止井涌或井噴的發生。另外在不需要下入工具時，還可以作為配合接頭來使用。實際上鉆桿浮閥就是個單向閥，它不阻礙泥漿的正循環，但能阻止井涌或井噴。減少泥漿的損失和保持鉆臺的清潔。
鉆桿浮閥分為箭形浮閥（柱塞閥）（Model F) 和翻板浮閥（全開式閥）（Model G)
閥芯參數
|
Valve size
|
D
Diameter of Valve
|
R
(D+1/32)
Diameter of Recess for Valve
|
L
Length of Valve
|
T
Diameter of Recess for Baffle Plate
|
ID of Valve
|
|
Model F
|
Model G
|
|
1R
|
1-21/32
|
1-11/16
|
5-7/8
|
1-5/16
|
1
|
N/A
|
|
1F-2R
|
1-29/32
|
1-15/16
|
6-1/4
|
1-1/2
|
1-1/4
|
1
|
|
2F-3R
|
2-13/32
|
2-7/16
|
6-1/2
|
1-29/32
|
1-9/16
|
1-1/4
|
|
3F
|
2-13/16
|
2-27/32
|
10
|
2-7/16
|
1-7/8
|
1-5/8
|
|
3-1/2IF
|
3-1/8
|
3-5/32
|
2-11/16
|
|
4R
|
3-15/32
|
3-1/2
|
8-5/16
|
2-15/16
|
2-5/16
|
1-31/32
|
|
4F
|
3-21/32
|
3-11/16
|
12
|
3-1/4
|
2-1/2
|
2-3/16
|
|
5R
|
3-7/8
|
3-29/32
|
9-3/4
|
3-3/8
|
2-3/4
|
2-1/4
|
|
5F-6R
|
4-25/32
|
4-13/16
|
11-3/4
|
4-9/32
|
3-1/4
|
2-7/8
|
|
6F
|
5-11/16
|
5-23/32
|
14-5/8
|
5-3/16
|
4-1/8
|
N/A
|