Although you might not think of it right away, assuring adequate tube line support is critical to keeping hydraulic, pneumatic or lubrication systems efficient, leak-free and easy to maintain. Once a proper tube line routing design is identified, the support system, or tube clamping, for this design needs to be laid out as well. While in some instances the support system can be placed after install, there are certain instances where clamping needs to be taken into account for proper tube line routing.
Clamping of tube lines serves three purposes, each discussed below: vibration dampening, reducing system noise and tube mounting.
Tube line failure can be caused by fatigue due to mechanical vibration. This vibration can also cause connections (or fittings) to loosen, result in leaking. Without proper tube clamping, vibration can travel through a system, causing failures much further down the line than where the main source of vibration is occurring. The greater the tube line length without proper clamp spacing, the greater the amplitude of vibration and likelihood of tube line failure. Properly anchoring tube clamps to a rigid structure will assist in effectively dampening vibration.
Figure 1: Recommended clamp spacing layout for dampening vibration in hydraulic tube and pipe systems.
Table 1: Recommended tube clamp spacing dimensions for dampening vibration in hydraulic tube and pipe systems.
Simply clamping several tubes together does not provide effective dampening by itself and can actually transfer vibration across lines, potentially creating more tube line failures. While there are clamp systems that allow for multiple tube lines to be clamped together, the clamp still needs to be attached to a rigid structure (frame, support, etc.) to properly dampen the vibration. Refer to Tube mounting below.
Valve operation, cylinder actuation and pump pulsations are just a few examples of the many factors that can contribute to hydraulic system noise. This noise can be carried and amplified through the tube lines connecting these various components. The proper use of a tube clamp system can reduce the amplification of the system noise caused by these types of components.
The use of proper rigid mounting will increase the service life of metal tube lines. Tube mounting can be completed with the use of an industrial clamping system (like Parker’s ParKlamp system) or through the use of products, such as the Mountie cap.
Depending on the style of tube clamp mounting used, there will be a different centerline height, so verify these dimensions with the manufacturer during tube clamp layout design.
A Mountie cap can be used in lieu of clamps by anchoring a tee fitting to the equipment’s structure (see Figure 2 below). This style of connection will need to be designed into the tube line routing, to ensure proper height of the tube lines from the mounting structure.
Figure 2: Mountie cap used with Triple-Lok 37° flare fitting for anchoring tube lines
Tube clamp systems come in many styles and materials. Polypropylene, nylon, and aluminum are just a few of the materials from which tube clamps can be manufactured. Multiple factors will used to determine the proper tube clamp material, application, temperature and environment being a few of those factors. For excessive vibration applications, a rubber sleeve can be utilized to further dampen the vibration in the system.
In conclusion, tube line routing and tube line clamping are not necessarily sequential tasks. Multiple factors need to be accounted for during both the design and implementation stages to ensure that the tube lines in your system will remain efficient, leak-free and easy to maintain.
These tables and illustrations show good examples of how to plan your clamping layout for Parker ParKlamp Inch Clamps, as well as the minimum dimensions Parker recommends for spacing any clamp assemblies.
Be sure to check out Dry Technology - The Guide to Leak-free Connections. This detailed guide addresses many of the issues, application considerations and practices to assist designers, assemblers and maintenance personnel who create and maintain dry (leak-free) systems,
Do you have any additional tips or stories from the field about designing and implementing tube line clamping systems? If so, please share by commenting using the link above. If you have any questions or comments, please post them and we will respond if warranted. To talk to our techConnect engineer team directly, they can be reached at Parker Tube Fittings Division, 614.279.7070.
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Written by Nathan Green, engineer at Parker Tube Fittings Division
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