Features of DBB and DIB Structure Ball Valves

The above drawing shows DBB structure. It is of single piston and is sealed inlet end.  The pressure can be automatically relieved for overpressure in the middle cavity, thus realizing the valve chamber and pipeline pressure balance. Besides, it has no installation direction requirement.

This kind of ball valve is used for the occasions where the medium will not be discharged outside the valve and will not increase the harm caused by the leakage of flammable and explosive media such as oil and natural gas.

DIB ball valves are divided into DIB-1 and DIB-2 two structures. It is applicable to high temperature, low temperature, flammable, explosive, toxic, corrosive and other hazardous medium pipeline systems. In addition, it is applied to the occasions where frequent maintenance and repair are required to ensure the personal safety of maintenance personnel to the maximum extent.

The above picture is DIB-1 structure, which is opposite to the DBB structure. Its characteristics are as followings.

Double piston, inlet seal, middle chamber seal, middle chamber overpressure cannot be automatically relieved, need to install the middle chamber safety valve (automatic pressure relief valve), no installation direction requirements.

The figure above shows DIB-2 structure, which is the combination of DBB and DIB-1 structure. Its features are as followings.

One side single piston, one side double piston, inlet end sealed. When the cavity overpressure, it will relieve pressure to the single piston end. It is necessary to clarify the pressure relief direction and the flow direction requirements when installing.