YSF4-35/80KJB Pressure Relief Valve

Pressure Relief Valve, YSF4-35/80KJB

YSF4-35/80KJB Pressure Relief Device


Pressure relief valve is suitable for oil immersed power transformer, power capacitor and cut-off and tap changer to protect oil tank.

When the oil immersed transformer fails in operation, some transformer oil is gasified due to the coil overheating, and the pressure in the transformer oil tank increases rapidly. At this time, the pressure relief valve acts quickly within 2ms to protect the oil tank from deformation or burst. When the pressure in the oil tank rises again and reaches the opening pressure, the pressure relief valve operates again until the pressure drops to the normal value. At the same time, it can also effectively prevent external air, dust, impurities and water vapor from entering the running transformer, so as to protect the transformer from damage.

Models: YSF4-35/80KJB

Ordering Code

YSF1_ordering code


Effective Caliber (mm) Opening Pressure (KPa) Closing Pressure (KPa) Sealing Pressure (KPa)



15 ±5 8 9
25 13.5 15
35 19 21
55 29.5 33


35 19 21
55 29.5 33
70 37.5 42
85 45.5 51
138 75 81

Flange Installation Dimensions

Caliber of oil-gushing tube Փ25 Փ50 Փ80 Փ130
Internal diameter of connection Փ45 Փ80 Փ130 Փ165
Center point distant of installation flange Փ90 Փ130 Փ170 Փ235
Diameter of bolt X units M10X3 M12X4 X12X6 M16X6

Screw Installation Dimensions

Caliber of oil-gushing tube Փ20 Փ25 Փ50
Hole in tank lid Փ32 Փ40 Փ57
Screw X step M27X1.5 M36X1.5 M60X2.0