浮閥通常安裝在鑽具接頭的標準孔中，用以控制鑽杆底部的液流。在停泵換鑽杆時，浮閥還能防止切屑從鑽頭噴嘴中返回。

Type	Dia. of Valve Assembly	Length Of Valve Assembly	Dia. Of Float Recess	Sub Box		Other Popular Connections
	mm(inch)	mm(inch)	mm(inch)	Connection	Depth Of Recess	Connection	Depth Of Recess
				API	mm(inch)	API	mm(inch)
1R	42.1(1-21/32)	149.2(5-7/8)	42.9(1-11/16)	2-3/8Reg.	231.8(9-1/8)	NC23	231.8(9-1/8)
2F-3R	61.1(2-13/32)	165.1(6-1/2)	61.9(2-7/16)	3-1/2Reg.	266.7(10-1/2)	NC31	260.35(10-1/4)
3-1/2 F	79.4(3-1/8)	254(10)	80.2(3-5/32)			NC38	362.0(14-1/4)
4R	88.1(3-15/32)	211.1(8-5/16)	88.9(3-1/2)	4-1/2Reg.	325.4(12-13/16)	NC44	331.8(13-1/16)
5R	98.4(3-7/8)	247..7(9-3/4)	99.2(3-29/32)	5-1/2Reg.	374.7(14-3/4)	NC50	368.3(14-1/2)
5F-6R	121.4(4-25/32)	298.5(11-3/4)	122.2(4-13/16)	6-5/8Reg..	431(17)	5-1/2IF	431.8(17)
When ordering or requesting quotation, if size out of above specification, pls. specify clearly.