Brass and Carbon Tube Fittings

DK-LOK offers a wide variety of Brass and Carbon tube fittings that are designed using industrial codes and specifications with additional Cutting-Edge Engineering on swaging action and sealing integrity. Our tube fittings provide excellent leak-free sealing on high-pressure gas, vacuum, impulse, thermal shock, heavy vibration, and many other stringent applications.

DK-LOK Tube Fitting consists of body, front ferrule, back ferrule, and nut. The features include:

• Excellent product range up to 2 in. and 50 mm OD.
• Additional engineering on sealing integrity and swaging action.
• Re-usable and predictable quality.
• Gaugable.
• Excellent leak-free sealing integrity on heavy vibration, vacuum, and impulse.
• Heat-Code Traceability.
• No torque transferring to connective tubing during installation.

Tubing:

For Safe, reliable and leak free DK-LOK fitting system, tubing should be considered as one of fitting components.

• Tubing is assembled by simple wrench make-up on DK-Lok fitting. This results in less assembly and maintenance costs.
• Tubing assembly on DK-Lok fitting is re-usable.
• Tubing is bendable. It allows lower pressure drop with fewer connections. This in turn reduces system costs because of less fabricating manpower.
• Pipe threading or welding is difficult to disassemble and re-assemble
• Piping requires skilled worker for welding & threading

Tubing Selection:

Hardness Tubing must be softer than fitting material. The metal tubing must be fully annealed and suitable for bending and flaring. Tubing hardness must be selected according to the information in the table 2 to 13.	Ovality Tubing in oval or out-of-roundness way not fit into the fitting. Do not force the tubing into the fitting; it may damage the fitting sealing system on nut, ferrules, and body.
Surface Tubing must have a surface free from scratches, draw mark, dirt, dust and flat spots.	Weld tubing Welded tubing should have a not measurable bead on its outside diameter.
Wallthickness The table 2 to 13 list tubing working pressure ratings in a wide range of wall thickness. A too thin wall may collapse and a too thick wall may not properly be deformed by the ferrule action. Do not use tubing wall thickness not listed in the table 2 to 13.	Pressure Rating  The pressure rating of DK-Lok Tube Fitting is rated to the working pressure of connective tubing. The allowable working pressure of tubing in various materials is listed in the table 2 to 13.

 

High Pressure Application

Pressure 500 psig (34.5 bar) or higher is considered generally high pressure. In the high pressure system scratches, draw mark, nicks, flat spots, and dirt on tubing may cause leakage.

• For gas application, select the gas applicable tubing wall thickness from Table 2 to 13.
• Follow the suggestion on tubing selection, handling, and installation.

Gas Application

DK-LOK tube fitting is designed for a wide range of leak free application including gas leak proof and vacuum tight service. Gases (helium, hydrogen, nitrogen, air, etc.) can escape even the most minute leak-path due to their very small molecules. Tube therefore must be handled not to have scratches, draw mark, nicks, flat spots, dust, and dirt.

Use NOT thin wall tubing for gas applications. Heavier wall tubing resists the ferrule action whereas thin wall tubing may collapse with little resistance to ferrule action. For Gas service, use the tubing wall listed on un-shadowed section in table 2 to 13.

Vacuum Application

DK-Lok Tube Fittings have been proved to be excellent vacuum tight seal in many applications including analytical industry. DK-Lok Tube Fittings comply with the leakage requirements of TA-LUFT 2002.

Cryogenic Application

DK-Lok Fittings in SS316 Stainless Steel provide highly reliable performance on cryogenic application. Cryogenic temperature is considered to be temperatures below -100℉ (-73℃). 

 

 

View Tube Fittings Catalog