What type of end fitting is used on Cogent TYPE-C™ columns?
Our Cogent columns and guard holders are manufactured by the leading machine shop that makes HPLC columns. The Valco fittings as an industry standard sealing depth are used.
Analytical column end fittings have a 0.4 mm bore and the standard material is Type 316 stainless.
The use of Direct Adaptive Di-Ad™ column connectors are recommended because they do not permanently lock into place on the connecting tubing, avoiding potential dead volume connection problems. A good connection can therefore be made every time, avoiding the issues that can occur when using a ferrule that gets swaged on the tubing.
Many problems are often caused by the initial installation by over or under tightening finger tight and standard fittings. If the tubing has been swaged into a column end, and is re-used on another part of the system or a different column brand, the seating depth must be the same as the other connector.
If the seating depth is too deep, the fitting will not seal inside the body and the tubing end may be damaged while tightening. If the depth is too short, the tubing end will not rest flush with the connector and a mixing chamber will have been created in the system.
These connections are critical when formed between the injector and column as well as the column and detector.
Click HERE for ordering information and pictures of the Di-Ad™ column connectors.