The main functions and features of the flow passage maintenance valve are mainly a kind of valve which is easy to disassemble and install during the pipeline maintenance. The valve structure is Youxu, reliable performance, eccentric sealing structure, light opening torque, large circulation area, convenient maintenance and other characteristics. The product can also be called C-type ball valve, which mainly relies on rotating hemisphere to make the valve unblocked or blocked. Its switch is light, small volume, can be made into a large diameter, reliable sealing, simple structure, convenient maintenance, sealing surface and spherical surface are often closed, not easy to be eroded by the medium. It is widely used in petroleum, chemical industry, urban water supply and drainage, etc.  
Valve model: flow passage maintenance valve q940h (electric type) q340h (manual turbine type), q640h (pneumatic switch type), dyq340h (on-line maintenance type), dyq340y (cemented carbide seal type on-line maintenance type), dyq340f tetrafluoro seal on-line maintenance type; the series models of flow path maintenance valve include pq640h (), pq640y and py640f.

1. The flow resistance of the flow passage maintenance valve is small, and its resistance coefficient is equal to that of the pipe section with the same length;
   2. Simple structure, small volume and light weight
   3. It is compact and reliable. At present, the sealing surface material of ball valve is widely used with good sealing performance, and it has been widely used in vacuum system
   4. Eccentric structure design, the valve can quickly leave the valve seat when it is opened, reducing friction and increasing service life
   5. The maintenance is convenient, the ball valve structure is simple, the sealing ring is generally movable, and it is convenient to dismantle and replace
   6. When the flow passage maintenance valve is fully open or closed, the sealing surface of the ball and valve seat is isolated from the medium, and the medium will not cause erosion of the valve sealing surface
   7. Wide range of application, diameter from small to several millimeters, large to several meters, from high vacuum to high pressure.

working pressure(MPa)		1.6~10.0 (Calss150-Calss600)
caliber(mm)		DN15-DN1200 1/2″-48″
Applicable media		Water, oil, gas, acetic acid, nitric acid and other media
Material Science	valve body	WCB CF8 CF8M CF3 CF3M
	sphere	WCB CF8 CF8M CF3 CF3M
	Stem	2Cr13 F304 F316 F304L F316L
	Sealing surface	PTFE RPTFE PEEK 司太立合金 碳化钨
	filler	Flexible graphite

Design code for flow passage service valve: API 6D API 608 BS 5351 GB / t12237
Structure length of flow passage maintenance valve: ASME B16.10 GB / t12221
Flange connection of flow passage maintenance valve: ASME B16.5 GB / t9113
Test and inspection of flow passage service valve: GB / T 13927 API 598 API 6D

Numerical notes in the flow passage maintenance valve diagram: 1 represents the valve body, 2 represents the compression ring. 3 is shaft sleeve, 4 is valve seat, 5 is ball crown, 6 is valve cover, 7 is packing, 8 is eccentric shaft.。

1.6MPaDimension of flow passage service valve under nominal pressure：

DN	50	65	80	100	125	150	200	250	300	350	400	450	500	600
L	178	190	203	229	254	267	292	330	356	381	406	432	457	509
H	242	269	292	330	345	370	405	480	520	570	630	695	740	860
D	165	185	200	220	250	285	340	405	460	520	580	640	715	840
D1	125	145	160	180	210	240	295	355	410	470	525	585	650	770
D2	99	118	132	156	184	211	266	319	370	429	480	54	609	720
C	20	20	20	22	22	24	24	26	28	30	32	34	36	38

2.5MPa公称压力下的流道检修阀外形尺寸：

DN	50	65	80	100	125	150	200	250	300	350	400	450	500	600
L	178	190	203	229	254	267	292	330	356	381	406	432	457	508
H	242	269	292	330	345	370	405	480	520	570	630	695	740	860
D	165	185	200	235	270	300	360	425	485	555	620	670	730	845
D1	125	145	160	190	220	250	310	370	430	490	550	600	660	770
D2	99	118	132	156	184	211	274	330	389	448	503	548	609	720
C	20	22	24	24	26	28	30	32	34	38	40	42	44	46

Statement: all text, data and pictures in this paper are only applicable for reference. Please contact us for details of performance parameters, structural dimension parameters, and flow passage maintenance valve price