Selecting the appropriate air bellows for vibration isolation is essential for maximizing system performance and longevity. In our engineering practice, we focus on identifying the right air bellows configuration by examining pressure requirements, material compatibility, vibration frequency, and mounting conditions. Each variable affects how well the air bellows isolate unwanted vibrations, reduce noise, and prolong machinery life. We begin by assessing the maximum static and dynamic loads the system must support. Load capacity directly correlates to the air bellow’s size, number of convolutions, and internal construction. For heavier applications, double or triple convoluted air bellows with higher load ratings offer superior damping. Next, we verify the natural frequency of each bellow at operating pressure. Optimal vibration isolation is achieved when the system frequency remains far from the excitation frequency. Technical data supports this, with frequencies ranging from 1.2 Hz to 4.6 Hz under normal conditions.
Identify the load and stroke requirements
Determining load and stroke is fundamental when choosing air bellows for vibration isolation. We start by calculating the maximum dynamic and static forces that the air bellow must support. This guides the selection between single, double, or triple convoluted designs, each offering different stroke lengths and load capacities. For instance, triple convoluted bellows typically offer the greatest stroke and load tolerance. Stroke length is critical in applications with significant movement. The selected air bellows must provide sufficient extension and compression without reaching physical limits. We examine both minimum and maximum compressed heights to prevent over-compression or overstretching. Stroke limitations are not just mechanical—higher stroke under pressure may introduce lateral instability. A double convolution unit may provide a stroke up to 310 mm, with load capacities exceeding 180 kN. Each Tevema bellow variant offers detailed performance charts to assist engineers in matching products to exact force and stroke profiles.
Consider natural frequency and damping
When designing for vibration isolation, natural frequency plays a pivotal role. Our approach ensures that selected air bellows have a low natural frequency—typically under 3 Hz at 6 bar—enabling them to isolate more than 99% of unwanted vibrations. The mismatch between the system excitation frequency and the air spring’s natural frequency determines how effectively it isolates. We analyze charts showing natural frequency at various pressures to ensure the air spring remains effective across load cycles. For systems with variable loads, uniform isolation properties are essential. This consistency prevents vibration transmission, even under changing load conditions. Tevema air bellows maintain a relatively constant frequency despite fluctuating weights. A 16-inch triple convolution unit, for example, can operate at a frequency as low as 2.00 Hz while supporting up to 75 kN. This level of damping ensures stable, high-performance isolation across industrial installations.
Choose the optimal design type
The design type of the air bellow affects installation, maintenance, and overall performance. We offer three main configurations: crimped, bead ring, and dismountable designs. Each has strengths depending on the application. For compact systems, the crimped design minimizes space and is ideal for permanent fixtures. The bead ring design allows modular integration, suitable for machines that require periodic replacement of components. It’s especially beneficial where fast mounting and demounting are needed. Dismountable designs offer the highest flexibility with removable top and bottom plates, enabling easier maintenance and part replacement without system disassembly. Each design is compatible with multiple elastomer compounds and metal qualities. We select galvanized steel, aluminum, or AISI-304 stainless steel based on environmental exposure and mechanical requirements. Crimped units support pressures up to 8 bar, while dismountable designs can be configured with four-ply construction for up to 12 bar performance.
Select the right material for your environment
Environmental compatibility is crucial when selecting air bellows for vibration isolation. We examine the operating atmosphere—exposure to ozone, chemicals, oils, or extreme temperatures—and match the application with an appropriate elastomer compound. Our options include:
- Natural rubber (NR/SBR) for general use with high dynamic load capacity.
- EPDM for outdoor, ozone, and high temperature resistance.
- Nitrile (NBR) for oil, grease, and fuel resistance.
- Chlorobutyl (CIIR) for chemical and acid exposure. For harsh environments, we recommend AISI-304 stainless steel end plates and bead rings to resist corrosion and chemical attack. In food, pharmaceutical, or chemical industries, this choice ensures long service life and system integrity. Where corrosion is not a concern, galvanized steel or aluminum offers a lightweight, cost-efficient alternative. Using unsuitable combinations reduces product life and performance. Our tailored selection process ensures longevity and minimal maintenance in the field.
Review mounting requirements and connection types
Proper mounting is essential to maintain the air bellow’s alignment and performance. We evaluate the installation space, plate dimensions, and fixation method. Depending on the series, air bellows can include threaded studs, blind nuts, or bolt holes for attachment. The F Series, for instance, offers crimped and bead ring closures with versatile mounting setups. The connection ports must also match system standards. Most configurations use G1/4\”, G3/8\”, or G3/4\” air inlets, and our selection ensures these align with existing fittings. We ensure the correct thread sizes and bolt patterns are used to prevent leakage or misalignment during operation. Clearances for lateral and angular movement are considered to prevent undue stress on the system. Some designs accommodate up to 25° angular deflection and 30 mm lateral misalignment, making them suitable for installations with imperfect geometries. Our in-depth review prevents premature failure due to incorrect mounting.
Balance size constraints with performance
Available space often limits the size of the air bellows. We analyze the envelope dimensions—minimum and maximum compressed heights, diameter, and stroke—and compare them to system constraints. When height is limited, single convolution designs with compact stroke offer good isolation without exceeding spatial boundaries. For systems requiring higher strokes within the same footprint, double or triple convoluted designs provide increased flexibility and force capacity. However, we must ensure stability at extended heights to avoid lateral movement or tipping. A compact 6-inch single convolution bellow may fit tight spaces with a height under 50 mm. The selected configuration must not only fit but also offer long-term durability. Overloading a small bellow in a tight space leads to frequent failure. Instead, we choose bellows that operate within 70–80% of their rated capacity. This extends product life, reduces downtime, and improves reliability.
Verify performance against technical data
Before final selection, we match customer requirements to the technical performance of available bellows. Our engineering team references detailed tables listing:
- Design height at rest
- Force output at 7 bar
- Natural frequency at 6 bar
- Maximum stroke and compressed height Using these parameters, we cross-check multiple models to ensure precise alignment with functional goals. For example, isolating a 60 kN load with less than 2 Hz frequency requires a high-capacity, low-frequency bellow—typically a large triple convolution model. We also assess safety margins for pressure capability and temperature range. Standard bellows operate up to 8 bar, while high-strength four-ply designs can reach 12 bar. This additional tolerance is ideal in systems with pressure spikes or demanding cycles. We always design conservatively to maximize performance.
Plan for long-term reliability
Our goal is not just immediate functionality but also long-term reliability. We examine how the air bellows will behave after years of continuous use. Factors like rubber fatigue, metal corrosion, and ozone exposure can degrade performance. Selecting materials and designs with built-in resistance ensures minimal maintenance. We recommend storing spare bellows in controlled environments as per ISO 2230, avoiding direct sunlight and ozone-emitting equipment. Proper storage preserves the rubber’s mechanical properties and ensures readiness when replacements are needed. Tevema bellows are engineered with maintenance-free performance in mind. Their robust construction and adaptable design reduce downtime and eliminate the need for lubrication or sealing elements. A well-installed unit can operate flawlessly for years under continuous vibration load. Our customers benefit from lower operational costs and increased system uptime by making the right selection from the start.