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All about Close Coupled Flush Ring

The chemical industry uses flush rings for diaphragm seals. These rings prevent clogging of the instrument connection. The technician mounts the ring between the process flange and the diaphragm seal. It has flushing ports and membranes. The flushing ports allow users to wash out particles from in front of the membrane. It also has a pressure chamber, which users can vent, drain, or fill with cleaning liquid. The user can then flush the chamber.

Why use Close Coupled Products?

We are often asked by users why we recommend close coupled products. That’s easy to answer: Users can save time and money while increasing their safety level. Close coupling reduces the risk of leakage. This feature is critical in the oil and gas, chemical, and petrochemical industries. These industries must provide storage for fuel, oil, gas, and various chemicals. They also have to store wastewater. The holding capacity of the storage tanks is often several million liters.

The tight seal on close coupled flush rings improves measurement results. It also increases plant safety. After all, some of the substances contained in the holding tanks are corrosive or toxic. Others are flammable or environmental hazards. The technician must ensure that there is a system to capture and dispose of all gases and liquids as required by law. The only exceptions are nitrogen, oxygen, and drinking water.

“Traditional” Assembly

Traditional flush rings use impulse lines, which connect a measuring device or transmitter to the system to collect and forward the corresponding parameters. This method has several disadvantages. First, it requires lots of planning, and it’s difficult to install. It is also time-consuming, and a potential source of errors. It is prone to leaks, which falsify the measurement results and impair safety.

Another problem occurs after the primary isolation valve is closed. A small amount of the pressurized medium remains in the pipeline section. This residual medium gets trapped between the primary isolation valve and the transmitter. The operator must collect and dispose of it in a manner that meets regulatory standards.

Impulse line flush rings call for several parts and accessories. These parts and accessories take time to select and buy. The buyer then has to do on-site activities such as inline commissioning. During the final assembling, technicians have to ensure that they don’t mix or use wrong single parts. They also have to create tight connections. They must have all the needed tools on site. They then have to test the assembly and mark the items.

Close Coupled Flush Ring

Unlike impulse lines, close coupled flush rings have a simple installation process. This type of flush ring is easy to handle. They are a true plug and play application. We deliver the flush rings assembled and tightened to customers’ specifications. We also deliver the corresponding documentation. All flush ring assemblies come equipped with a metal tag plate. This plate identifies its measuring spot on site and the properties of the assembly.

Engineers and technicians can start the assembling process right away. They don’t have to lose time commissioning loose parts, bending pipes, and testing. Technicians can omit pressure trials on the measuring line. Close coupled flush rings also do not call for time-consuming welding work. The assembly is compact and straight. It is very stiff, resistant against vibrations, and rodable. These qualities guarantee that it will last a long time.

Close Coupled vs. Traditional Assembly

The table shows how companies can save a lot of time and money and increase their safety levels when they use close coupled flush rings.

Traditional Assembly Close Coupled Assembly
Several single parts needed Compact, roddable, fixed and stiff in design
Single parts can get loose A wide range of materials are combinable
Requires a lot of documentation Fully traceable documentation
Has to be tested and painted on site Supplied fully tested and painted
Reliable & safe
Easy to set up on site
One single supplier
Image Source: © AS-Schneider