Multi-size injector port system

In a sample injection apparatus which can receive a sample at low pressure and then inject it at high pressure into a chromatographic column device for analysis, the improvement comprising:

• an injection apparatus frame having a tube coupling hole with a cylindrical inner hole portion of a first small diameter, a tapered middle hole portion, and a threaded outer hole portion;
• a first ferrule which has a hold of a diameter to closely receive a tube of said first small diameter, and a tapered forward portion for sealing to said tapered middle hole portion;
• a second ferrule which has a larger hole of a diameter to closely receive a tube of a second diameter that is at least about twice said first diameter, and a tapered forward portion for sealing to said tapered middle hole portion;
• a screw which is threadable in said outer hole portion and which can press the forward portion of at least one of said ferrules against said tapered middle hole portion, said screw having a hole which can receive a tube of at least said first diameter;
• a first tube with an end portion being of substantially said first diameter, which can lie in a first position in extension through said first ferrule and with an end portion lying in said inner hole portion;
• a second tube with a tip, and being of said second diameter, which can lie in a second position in extension through said second ferrule and with said tip lying substantially against said tapered middle hole portion, when said first tube and first ferrule are not in said hole.

A method for enabling the installation of a second tube of a larger diameter and then a first tube of a smaller diameter in a frame of a chromatographic analyzing system comprising:

• forming a tube coupling hole in said frame, with a cylindrical inner hole portion of substantially said first diameter, a tapered middle hole portion, and an outer hole portion;
• projecting the end portion of a second tube of said second diameter through a second ferrule, pressing the tip of said second tube against said tapered hole portion at a location spaced outwardly from said inner hole portion, and pressing a tapered forward portion of said second ferrule against said tapered hole portion to seal said second ferrule to said coupling hole and to said second tube;
• removing said second tube and second ferrule from said hole;
• projecting the end portion of a first tube of said first diameter through a first ferrule, pressing the end portion of said first tube deeply into said inner hole portion and pressing said first ferrule against said tapered hole portion to seal said first ferrule to said coupling hole and to first tube.