Tube End Preparation
- ENDS MUST BE CUT SQUARE for best results. Tube cutters are satisfactory for most tube materials but tend to work harden stain less steel. Use of a hacksaw with a suitable guide for squareness is preferred.
- BURRS MUST BE REMOVED inside and outside for proper entry into fitting to prevent system contamination and/or restricted flow.
- TUBE END MUST BE CLEAN. Remove all filings, chips, and grit before attachment of fittings.
- ALWAYS MAKE SURE TUBE IS IN ALIGNMENT WITH FITTINGS. Tube line fabrication (bend angles and measured lengths) must be accurate so that the tube end easily enters the fitting in proper alignment. Do not force an improperly fitted tube line into the fittings.
- ALWAYS MAKE SURE TUBE END IS BOTTOMED AGAINST THE SHOULDER IN THE FITTING BODY. This is necessary to prevent movement of the tube while the nut forces the ferrule to grip the tube and to seal through any imperfections that may exist on the outside tube surface.
- NEVER PERMIT THE FITTING BODY TO ROTATE DURING TUBE END MAKE-UP USE TWO WRENCHES. Assemble port connectors to components first and hold with a wrench while making up the tube joint. All types of union bodies must be held while each of the tube ends is made up.
- NEVER ATTEMPT TO MAKE UP BY TORQUE OR “FEEL”. All instrumentation fittings are designed so that the ferrule(s) must move a prescribed distance in relation to the tube to effectively grip and seal. The force required to accomplish this can vary a great deal with size, tube wall thickness and normal manufacturing variables or tube and fittings.
- ALWAYS TURN THE NUT THE PRESCRIBED AMOUNT REGARDLESS OF TORQUE REQUIRED. NORMAL MAKE UP
If you mark the nut before you start, you will know when you have finished that you did it right.
NOTE: FITTING END PLUGS REQUIRE ONLY 1/4 TURN FROM FINGER TIGHT MAKE UP IN ALL SIZES.
A disassembled joint can be remade simply by retightening the nut to the position of the original make up. For maximum number of remakes, mark the fitting and nut before disassembly. Before retightening, make sure the assembly has been inserted into the fitting until the ferrule(s) seats in the fitting. Retighten the nut by hand. Rotate the nut with a wrench to the original
position as indicated by the previous marks lining up. (A noticeable increase in mechanical resistance will be felt indicating the ferrule is being resprung into sealing position.) Then snug the nut 1/12 turn (1/2 hex flat) as shown from A to B, past the original position.
Tube Fabricating Equipment
Parker offers a complete line of instrumentation tube fabrication equipment. This high quality package includes:
- Ferrule Pre-Set Tool(s).
- Stainless Steel Tube Cutter(s).
- Stainless Steel Deburring Tool(s).
- Hand Benders.
- Inspection Gauges.
For further information see Catalog 4290-INST.
Alternate Instructions — Special Cases
In some special cases it is desirable to alter the standard make up procedure for Parker Tube Fittings. An example would be a thermo couple fitting in a vacuum or low pressure system. To minimize deformation of probe use 3/4 turn for size 4 (1/4” and 1 turn for size 6 (3/8”) and up.
Parker Tube Fittings can be used with a wide variety of tubing materials and a broad range of tube wall thicknesses. Parker Tube Fitting seal equally well on both thin wall and heavy wall
tubing. Tubing and fitting material should be selected to be compatible with the fluid media. Due to thermal expansion characteristics and chemical stability, the tubing should be of the same material as the fitting. Care in handling should be used to avoid scratching or abrading the surface of the tube.
Typical Raw Material Specifications
|MATERIAL||TYPE||ASTM TUBING SPEC||CONDITION HARDNESS||MAXIMUM RECOMMENDED|
|Stainless Steel||304, 316, 316L||ASTM•A•269,A•249,A•213,A632||Fully Annealed||90 Rb|
|Copper||K or L||ASTM-B75,B68 B88(K or L)||Soft Annealed|
|60 Max.Rockwell 15T|
|Fully Annealed||72 Rb|
|Aluminum||Alloy 6061||ASTM B•210||T6|
|Monel™||400||ASTM B•165||Fully Annealed||75 Rb|
|Alloy C-276||C-276||ASTM•B•622,||Fully Annealed||90 Rb|
|Alloy 600||600||ASTM B•167||Fully Annealed||90|
|Carpenter 20™||20CB•3||ASTM B•468||Fully|
|Titanium||Commercially,Pure Grade2||ASTM B•336||Fully Annealed||99|