| Coordination Type |
Nominal diameter d[mm] |
Tolerance zone (mm) |
Compatibility characteristics |
Application Examples |
| hole |
axis |
| Extremely large interval Clearance fit |
>6–18 |
d±0.05 |
(d-0.3)±0.05 |
A large gap is suitable for cases that may be skewed. Connection, suitable for cases caused by welding or other reasons. Deformed parts are also widely used in drilling. Rough-machined parts |
1. Fit between bolts and bolt holes 2. Fit between the nut and the welded pipe 3. The split-type valve disc and stem assembly of the NV needle valve and the hard-sealed safety relief valve |
| >18–50 |
d±0.06 |
(d-0.4)±0.06 |
| >50–120 |
d±0.1 |
(d-0.6)±0.1 |
| Large gap Coordination |
>6–18 |
d±0.03 |
(d-0.23)±0.03 |
Low manufacturing cost, used in applications without direct conduction. Required cooperation for assembly accuracy. Low connection, suitable for cases where the shaft and housing cannot… or non-contact sports coordination |
1. The valve stem of the needle valve and the globe valve is fitted with a packing gland or a compression nut. 2. KHA and BKC ball valves (packed seal), with stem-to-body fit 3.4KH ball valve (with a guide ring on the valve stem), with the valve stem mating with the valve body. 4. EVL pneumatic valve (with a guide ring on the flow‑diverting tube), where the flow‑diverting tube is fitted to the housing. |
| >18–50 |
d±0.04 |
(d-0.28)±0.04 |
| >50–120 |
d±0.06 |
(d-0.36)±0.06 |
| Medium spacing Clearance fit |
>6–18 |
d±0.02 |
(d-0.16)±0.02 |
A looser clearance allows for flexible movement and is less likely to… Clogged by fine particulate matter, widely used in The guidance requirements are not very high and relatively easy to operate. Dynamic coordination |
1. Dynamic fit between the check valve spool and the valve seat 2. Dynamic fit between the solenoid valve’s moving core and the magnetic guide tube 3. Dynamic fit between the DVG throttle valve stem and the valve body 4. Dynamic fit between the spool and the valve body of the NQ pneumatic valve |
| >18–50 |
d±0.03 |
(d-0.20)±0.03 |
| >50–120 |
d±0.04 |
(d-0.26)±0.04 |
| Small gap Coordination |
>6–18 |
d±0.015 |
(d-0.10)±0.02 |
Used for interference fits requiring a secure centering. It can also be used for applications involving both relative motion and providing… Better centering, suitable for guide rings, Dynamic fit of the support ring and sliding bearing |
1. Fit between the RD check valve spool seat and the valve body 2. The stem–body sliding fit of ball valves such as BKH (with O-ring sealing on the valve stem) 3. Dynamic fit between the EVL and MKH valve guide rings and the flow‑guiding tubes 4. Dynamic fit between the piston guide ring and the housing of MJ and MJH solenoid valves 5. KHA ball valve copper guide ring (sliding bearing) with a sliding fit to the valve stem |
| >18–50 |
d±0.02 |
(d-0.12)±0.02 |
| >50–120 |
d±0.025 |
(d-0.16)±0.03 |
| Very small room A gap is not fate. Dynamic coordination |
>6–18 |
d±0.02 |
(d-0.04)±0.015 |
Used for better centering and without relative… Coordinated motion. Used for guide rings, supports Bushing rings and sliding bearings on the housing or shaft It is also used for the outer circumference of packing seals. and the fit of the inner bore |
1. KHA/BKC ball valves, needle valves, and check valves with PTFE packing and in the packing chamber Fit between the hole and the valve stem 2. Fit between the EVL and MKH valve guide rings and the housing mounting holes 3. Fit between the stem guide ring of BKC, FRKC, and 4KH ball valves and the fixed mounting holes in the valve body. 4. Interference fit between the plastic support ring and the housing of the DG and DS rotary joints |
| >18–50 |
d±0.03 |
(d-0.05)±0.02 |
| >50–120 |
d±0.04 |
(d-0.07)±0.025 |
| Very small room Gap motion Coordination |
>6–18 |
d
0
+0.014
 |
d
-
0.05
-
0.04
 |
Extremely small gaps can form liquid-filled voids. Sealed, suitable for low-speed applications and Precision positioning fit |
1. Clearance sealing between the spool and the housing of a hydraulic slide valve |
| >18–50 |
d
0
+0.018
 |
d
-
0.06
-
0.05
 |
| >50–120 |
d
0
+0.024
 |
d
-
0.09
-
0.07
 |
| Transition Coordination |
>6–18 |
d±0.015 |
d
0
+0.02
 |
In 70% of cases, driving in a wooden hammer will result in a gap. Clearance, a relatively tight fit |
1. BKC ball valve, MKH electric valve: cylindrical pin (locating pin) mating with the valve body. |
| >18–50 |
d±0.02 |
d
0
+0.03
 |
| >50–120 |
d±0.025 |
d
0
+0.04
 |
| Interference Coordination |
>6–18 |
d±0.02 |
(d+0.07)±0.015 |
Press-fit insertion can be used for light loads. Simple fixation, also suitable for steel and aluminum, Fastening of copper and other light alloys, as well as plastics |
1. Fixing between the EVM06 and EVM10 compression rings 2. The red copper short-circuit ring embedded in the core of the AC solenoid valve is interference-fitted. 3. Interference fit between the NK and DVG throttle valve screw sleeves and the rotary caps. 4. Interference fit between the CPE and ATR check valve spool seat and the valve body |
| >18–50 |
d±0.03 |
(d+0.09)±0.02 |
| >50–120 |
d±0.04 |
(d+0.14)±0.03 |
| Scrolling axis Cooperation and compliance |
>6–18 |
D
0
+0.03
 |
d±0.01 |
The inner ring of the rolling bearing and the shaft are fitted with an interference fit. The outer ring of the rolling bearing and the bearing housing bore are extremely small. Clearance fit |
|
| >18–50 |
D
0
+0.04
 |
d±0.015 |
| >50–120 |
D
0
+0.05
 |
d±0.02 |
| Keyway pin Coordination |
2–10 |
D
0
+0.04
 |
—— |
Key pins (GB/T 13829) have along the pin body’s generatrix… Three grooves ensure the pin holes remain securely fastened and do not loosen. It can withstand vibration, and the pin holes do not require reaming. |
BKH, RKH, and SKH ball valve groove pins and pin holes mating |
