1.General
Ball valves are widely used due to advantages such as low flow resistance, rapid and convenient operation and excellent sealing performance.

Fluorine lined ball valves are extensively used in highly corrosive media, low-pressure, and low-temperature working condition. However, application of fluorine lined ball valve is limited due to drawbacks of lining including easy to aging, surface blistering, and easy to peeling under certain vacuum pressures.

Ceramic lined ball valves offer advantages such as strong corrosion resistance, wear resistance, erosion resistance and excellent sealing performance. Therefore, ceramic lined ball valves perform well in applications involving highly corrosive media such as phosphoric acid, monochloroacetic acid, concentrated hydrochloric acid and pure bromine systems.Ceramic lined ball valve can be also used in slag removal system for urban heating plant where both corrosion resistance and abrasion resistance are required.

2. Ceramic ball valve sealing pair types and characteristics

There are soft-seat and hard-seat types for ceramic lined ball valves.‌Soft seat‌ ceramic lined ball valves are primarily used for highly corrosive media without particles, offering a service life 2-4 times longer than Monel or Hastelloy valves.
‌Hard-seat‌ ceramic lined ball valves feature excellent wear resistance performance as structural ceramic components for both the ball and seat, with hardness reaching approximately ‌HA90‌.Due to the unique self-lubricating properties of zirconia ceramics, which effectively reduces contact wear between the valve ball and the valve seat, and also lowers the torque required to operate the valve during opening and closing.As a result,the opening torque of ceramic lined ball valve is ‌25%-50% lower‌ than that of metal hard-seal ball valves of the same size. Additionally, ceramic lined ball valves offer superior sealing performance. V type ceramic lined segment ball valve can work as control valves, significantly expanding the application scope of ball valves.

3. How to select ceramic material ?

There are many types of ceramic material with different performance .The ceramic material should be selected according to the application of ceramic parts during the valve design process.For ceramic ball valves, as the ball component undergoes significant torsional stress during operation, high-strength and high-toughness zirconia-based materials (such as ZrO₂+Y₂O₃, ZrO₂+MgO, or ZrO₂+CeO₂)‌ should be selected. Ceramic lined ball valve seats and linings may adopt alumina (Al₂O₃) or zirconia ceramics, as these ceramic materials not only demonstrate superior mechanical properties but also feature low thermal conductivity, excellent insulation, and thermal expansion coefficients closely matching metals‌.The exceptional resistance to strong corrosion and abrasion of structural ceramics enables their wide-ranging applications‌.


Ceramic material performance table

Item	Y-ZrO2	Mg-ZrO2	90 Al2O3	95 Al2O3	99 Al2O3	SiC	Common ceramic	Carbide alloy
Density ,g/cm^3	6.0～6.05	5.72～5.74	3.45～3.55	3.6～3.75	3.9～3.95	3.15～3.25	3.0～3.5	14～18
Hardness ,HRA/C	87	85	90	90	92	94	50～60	70
Flexural strength,Mpa	1150	900	350	370	450	470	20～50	2000
Fracture toughness,MN/m^(3/2)	10～12	13～15	3.4	3.6	4.5	4	/	20
Compressive strength,MPa	2000	1800	1700	2000	2200	/	/	4000
Thermal shock resistance,°C	87	110	/	/	50	75	/	500
Thermal expansion coefficient,x10^(-6)/°C	9.6	10	7.6	7.8	8.3	4	/	7
Modulus of elasticity,Gpa	200	200	310	330	350	400	/	600
Water absorption	0	0	0.02%	0.01%	0	0.5%	5～10%	/
Corrosion prevention(normal atmospheric temperature)	Good	Good	Good	Good	Good	Good	Good	Not Good

4. Conclusion

Compare to metal seated ball valve ,ceramic lined ball valves achieve better performance in wear resistance,corrosion resistance and slurry flow regulation.
Ceramic lined ball valves expands the application scope of ball valves ,they can fully replace precious metal ball valve such as Monel alloy ball valve , titanium alloy ball valve , and Hastelloy alloy ball valves.
With continuous improvements in the mechanical properties of structural ceramics and further optimization of valve design, ceramic ball valves have gained widespread applications in industries such as petrochemicals, pharmaceuticals, paper manufacturing, as well as emerging industry like poly silicon and lithium battery production.