Hydraulic guide strips, also known as guide bands or wear strips, support the piston and piston rod inside a cylinder. They absorb lateral forces acting on the cylinder during operation and prevent metal components from coming into direct contact. Without proper guidance, the cylinder wall can wear, the piston rod can become misaligned and the seals can fail prematurely.
Unlike a preformed guide ring, hydraulic guide strips are supplied on rolls or in lengths and are cut to the required size. This makes it possible to cover almost any diameter with a limited number of products. Techniparts supplies every brand and size.
A hydraulic guide strip is a sliding and guiding element installed in a groove on the piston or in the cylinder head. The strip supports the moving components of the cylinder and absorbs radial loads.
This helps prevent the piston from contacting the cylinder wall or the piston rod from contacting the cylinder head. This protects not only the metal components, but also the surrounding seals.
Unlike a preformed guide ring, a guide strip does not have a fixed diameter. The required length is cut from strip material with a specific width and thickness. This means that a relatively small number of standard sizes can be used for many different cylinder diameters.
A guide strip and guide ring perform the same basic function: guiding moving components and absorbing lateral loads. The main difference lies in their design and installation.
A hydraulic guide ring is supplied with a fixed diameter and is ready for installation in the corresponding groove.
A guide strip is selected according to its width and thickness and then cut to the required length. This provides considerable flexibility for cylinder repair companies, large diameters and non-standard cylinder dimensions.
Hydraulic guide strips can be used to guide either the piston or the piston rod. The installation position determines how the required strip length is calculated.
For piston guidance, the strip is installed in a groove on the piston. The outside of the guide strip runs along the cylinder wall and helps keep the piston centred.
For piston rod guidance, the strip is installed in the cylinder head. The inside of the guide strip supports the moving piston rod. Because the effective diameter is different, the cutting length must be determined separately for each position.
The material of a hydraulic guide strip determines properties such as load-bearing capacity, friction, wear resistance, sliding speed and temperature resistance. The correct choice therefore depends strongly on the load and operating conditions.
Phenolic fabric and phenolic composites have a high load-bearing capacity and are widely used in heavy-duty hydraulic applications with considerable lateral forces, such as mobile hydraulics, earthmoving equipment and lifting systems.
Bronze-filled PTFE offers very low friction and good sliding properties. This material can be suitable for higher sliding speeds and applications where stick-slip should be minimised.
POM and polyamide provide good dimensional stability and can be used for general hydraulic guiding applications. The exact load capacity depends on the material and profile.
Fabric laminate can be used where a combination of load-bearing capacity, flexibility and wear resistance is required. Depending on the design, this material can be suitable for long strokes, short guiding distances or slight piston-rod deflection.
The required width of a hydraulic guide strip is determined by factors including the radial load, diameter and permissible surface pressure of the material.
A material with a high load-bearing capacity generally requires less width for the same radial force than a material with a lower permissible load. Material and width should therefore always be selected together.
For machines with high lateral forces, a phenolic fabric guide strip can be suitable because of its high load-bearing capacity. At lower loads and higher sliding speeds, a material with lower friction may be more suitable.
In addition to load-bearing capacity, friction also plays an important role. A guide strip with a high coefficient of friction can contribute to irregular movement at low speeds or during small movements.
Stick-slip occurs when a moving component initially sticks and then suddenly breaks free. Materials such as certain PTFE compounds offer low friction and can help reduce this effect.
Hydraulic guide strips are generally specified using two dimensions: the width and thickness of the material.
The width b is measured in the longitudinal direction of the cylinder and must correspond to the groove width.
The thickness s is the radial height of the guide strip. Together with the groove depth, this dimension determines the final position of the guiding element.
A guide strip is cut to the correct circumference based on the effective diameter. The calculation should be based on the centreline of the material rather than solely on the nominal piston or rod diameter.
After installation, a small joint gap must remain between the ends of the guide strip. This space allows for expansion of the material caused by temperature and, for certain materials, moisture absorption.
If the ends meet without sufficient clearance, the strip can bind during operation. This can result in increased friction, damage or blockage of the cylinder. The required joint gap should be selected according to the material, diameter and temperature.
Proper guidance is important for the service life of the seals in a hydraulic cylinder. When a guide strip is worn, the piston and piston rod can move laterally.
As a result, a hydraulic rod seal can be loaded unevenly and wear prematurely.
A hydraulic piston seal can also be subjected to additional loads due to insufficient guidance. During a cylinder overhaul, always inspect the complete sealing and guiding arrangement.
A worn guide strip can result in increased lateral play of the piston or piston rod. This can cause metal components or seals to be loaded unevenly.
If a rod or piston seal repeatedly becomes damaged on the same side, this may indicate worn guidance, misalignment or excessive lateral loading.
With advanced wear, direct contact between metal components can occur. This can cause scratches or other damage to the cylinder wall, piston or piston rod.
In addition to mechanical loading, the operating environment of the cylinder should also be considered. Temperature, moisture, chemicals and cleaning methods can influence the material selection.
Special food-grade PTFE versions can be used for applications in the food industry. Always check which food-contact regulations, cleaning agents, CIP or SIP processes and temperatures apply to the specific installation.
Hydraulic guide strips are used in various hydraulic cylinders and machines where the piston or piston rod requires support against lateral loads.
Excavators, cranes, aerial work platforms and other heavy machinery can generate high lateral forces. Materials with a high load-bearing capacity are therefore commonly used.
Guide strips are also used in tractors, agricultural machinery, forklift trucks and mobile hydraulic systems to provide stable guidance for cylinder components.
Other applications include hydraulic presses, production machinery, pumps and installations in the food industry.
Techniparts supplies hydraulic guide strips from various manufacturers, including versions from Freudenberg Sealing Technologies and Dichtomatik.
Existing guide strips can often be identified by their width, thickness, material and type number. This makes it possible to find a technically suitable equivalent for many existing machines.
Guide strips can be supplied on rolls, cut to length or as pre-cut strip sections. For older machines, inch sizes and non-standard grooves, alternative widths, thicknesses and cutting lengths are also possible.
During a cylinder overhaul, it is advisable to inspect not only the guide strips but also the other sealing and guiding elements.
For fixed, preformed guidance, take a look at our hydraulic guide rings.
Also inspect the hydraulic rod seals and hydraulic piston seals.
Hydraulic wipers are used on the outside of the cylinder to remove dirt and contaminants from the retracting piston rod.
A hydraulic guide strip supports the piston or piston rod, absorbs lateral forces and helps prevent direct metal-to-metal contact inside the hydraulic cylinder.
A guide ring has a fixed diameter. A guide strip is selected according to width and thickness and then cut to the required length.
Phenolic fabric is commonly used for high lateral loads. When low friction and higher sliding speeds are important, bronze-filled PTFE may be more suitable.
The joint gap gives the guide strip room to expand due to temperature and possible moisture absorption. Without sufficient clearance, the material can bind.
Indirectly, yes. Worn guidance can cause the piston or rod to become misaligned, resulting in uneven loading and accelerated wear of rod and piston seals.
The main dimensions are the width (b) and thickness (s). The required length is then calculated according to the installation position, diameter and required joint gap.
Yes. Depending on the version, guide strips can be supplied on rolls, cut to length or as a strip section for a specific diameter. Non-standard widths and thicknesses are also possible.
Receive personal advice or a tailored quotation from our product specialists. Fill in the form and discover which Z - Hydraulic Guide Rings - Nieuw best fit your needs.
Nederlands 
Deutsch 