Technical Support

4. Tubing Connection

When making a connection with either stainless steel tubing or plastic tubing, the tubing has to be pushed toward the end fitting. If the tubing cannot reach the bottom of the end fitting, as shown in Figure 1, there is a dead volume left in the connection and peaks are distorted. Plastic tubing is so soft that it has to be carefully cut to avoid a diagonal or compressed cut surface, which can make a dead volume or pressure increase. Our “clean cutter” can keep the cut surface clean.

When a connection consists of stainless steel tubing and metal parts, it is sometimes impossible to change the positions once the they are fixed. If this tubing is connected to a column with a different end fitting type, a dead volume can be created. Most UHPLC systems employ UP type fittings instead of Waters type fittings, which are commonly used in conventional HPLC systems. In such a case, it is convenient to use fittings compatible to any end fitting,