- QL has the DBB ball valves /Double block and bleed ball valves/Double isolation and bleed ball valves in ranges design,material, size, pressure and ends connections, providing reliable isolation solution for petrochemical, transmission and storage, natural gas industrial processes, mainline and manifold valves in liquid pipelines etc.
- What's DBB ball valves /Double block and bleed ball valves/Double isolation and bleed ball valves ?
- The DBB ball valve has two types design one is Double block and bleed ball valve in union unit body and anther is traditional Double block and bleed ball valve in multiple valves unit.
- See fig. One union valve unit Double block and bleed ball valve
- See fig. Traditional multiple three valves unit Double block and bleed ball valve
- QL DBB ball valve /Double block and bleed ball valve is designed with two balls and seats sealing in one union unit valve body bubble tight shut off, and has the bleed valve system in cavity between the two balls. The two balls have each dependant operation mechanism to seal bubble tight and offers the most reliable isolation performance for severe medium.
- It is the same function like two ball valves combined with bleed/vent valve assembled in sequence pipeline.But it has compact structure for designed two balls in union body, require less assembly space,easy operation, cost effective at the same time satisfying double-isolation requirements of upstream and downstream in special process for safety management systems.
- Compared with two ball valves assembly together, DBB valve reduced the valve cost , save the valve assembly space, and avoid less valve connection leak point. The operation of the double block and bleed isolation performance become more efficient through all function in one body.
- DBB ball Valves suitable for Oil & Gas , processing, transportation, distribution, chemical and petrochemical refining on above ground and below ground installations where the shut down plant is not affordable but the repair or clean is compulsory, the DBB system which will depressurize the system and isolate a particular section and then can work on it without interfering whole process plant.
- What’s the DBB ball valve and it’s application advantage ?
- ● Zero leakage, Less leakage spot
- ● Less installation space
- ● Easy operation in one union body
- ● Less cost
- ● Integrated reliable double isolation for safety factor
- QL DBB ball valve/double block and double bleed ball valve is designed to replace the complex connection of multiple valves in the traditional pipeline.
- It reduces the leakage points in the system and quickly realizes the functions of block and bleeding. DBB double ball valve saves the installation space to the greatest extent.It simplifies the installation procedure,reduces the pressure of the pipeline system, easy all in one valve operation , facilitates the cleaning and maintenance of instruments and reduces the cost.
- DBB ball valve has double insolation and bleed functions. The valve has two balls with seat sealed blocked as isolation, and one needle valve in the middle for bleed. It assures the zero leakage.
- Isolation is important in cases where leakage through a valve could have major consequences. Once the fluid is isolated, the bleed mechanism can drain the area between the two valves or two seating surfaces. This is important for maintenance and integrity check situations where leakage can be monitored in the downstream pipe safely.
- The primary function of a double block and bleed system is for isolation and the secondary function is for intervention.
- Under certain conditions double block and bleed systems are needed to prevent product contamination or where it is necessary to remove essential equipment from service for cleaning or repairs while the unit continues in operation.
- Of course, such equipment must be provided with a spare or it must be possible to bypass it temporarily without shutting down the unit.
- Product case
- QL brand DBB ball valves are used in applications where critical isolation is needed to ensure that leakage does not occur. Both valves can be used in a variety of applications and markets, such as LNG, petrochemical, transmission and storage, natural gas industrial processes, mainline and manifold valves in liquid pipelines, and refined products transmission lines.