Buy lowpriced softstart fittings by Parker Legris

Buy Parker Legris Soft Start Fittings at Favorable Prices

Soft start fittings from Parker Legris reduce sudden pressure peaks during pressure build-up in pneumatic systems, protecting valves, hoses, cylinders, and large-volume consumers from mechanical stress. The design combines precise throttling characteristics with robust connection options and sealing systems, ensuring harmonized start-ups in production lines, painting processes, handling robots, and disassembly/assembly lines. On this category page, you will find a selection of designs in nickel-plated brass and polymer, various thread and hose connections, as well as variants for inline and screw-in mounting.

Construction and Materials

Standard versions consist of nickel-plated brass as a corrosion-resistant metal option and technical polymers for reduced mass and chemical resistance. Nickel-plated brass offers high mechanical strength, temperature resistance, and good corrosion resistance in industrial environments. Polymer versions reduce weight and enable electrical insulation as well as improved resistance to certain chemicals and cleaning agents. Valve cores and throttle spindles are usually made of hardened steel or stainless steel to minimize wear during frequent control movements. Seals use NBR (nitrile rubber), FKM (Viton), or EPDM depending on temperature and media requirements; FKM is preferred for higher temperatures and oil-containing applications, EPDM for steam and alkaline media.

Materials and typical application advantages:

• Nickel-plated brass: high strength, temperature stability, good sealing; suitable for general industrial applications.
• Technical polymers: lower mass, electrical insulation, chemical resistance; ideal for corrosive environments and mobile devices.
• Internal components made of stainless steel or hardened steel: long service life with frequent control cycles.
• Seals: choice of NBR, FKM, EPDM depending on medium and temperature.

Connections, Designs, and Installation Positions

Soft start fittings are available in various connection standards: metric threads (ISO/EN), BSPP/BSPT, and quick-connect fittings for plastic or PU hoses. The most common designs are inline throttles with adjustable spindles, check valve combinations (throttle with integrated check valve), and screw-in modules with integrated fixed connections. For space-critical applications, compact angle connections are available. In terms of mounting, the fittings are designed so that the adjustment spindle is accessible either frontally or radially; some models offer a lockable adjustment nut to secure the desired flow limitation.

Functional Characteristics and Performance Data

Important technical data to consider during use include nominal flow rate (l/min), maximum operating pressures (typically up to 16 bar for metal versions), pressure loss in the closed position, temperature range (polymer typically -20 °C to +80 °C; nickel-plated brass often -20 °C to +120 °C), and transient response. For applications with high volume flow or long pipe lengths, specially dimensioned soft start modules are required to control pressure rise over longer periods to avoid pressure waves in pipe network systems. The throttling characteristic is usually linear or progressive; in process plants, knowledge of this characteristic curve is important for correctly planning start-up times and pressure rise.

Practical Application Examples

Brief description: Three practical scenarios with specific product selection, installation instructions, and effects on the system and process.

Example 1 – Robot cells in series assembly: In an assembly line with six industrial robots, valve damage and positional deviations repeatedly occur during simultaneous start-up of the compressed air supply. The solution involves installing Parker Legris soft start fittings in nickel-plated brass directly in front of the main valve islands. The throttles are set to limit the pressure rise to 0.5–1 bar/s. Result: Reduced shock load on valve tappets, fewer mispositions, and a 40 percent reduction in maintenance intervals.

Example 2 – Painting and drying system: In a spray booth, rapid pressure build-up leads to splashing and uneven spray patterns. Here, polymer-based soft start fittings in combination with EPDM seals are used to ensure chemical resistance to solvents. The fittings are installed on the supply lines of the dosing pumps and set so that the pressure rise occurs over 2–3 seconds. Result: More consistent spray pattern, reduced rework, and lower material consumption.

Example 3 – Compressed air network in metal processing: A hall supply with long pipe runs generates pressure surges during start-up, damaging filters and measuring devices. Here, inline soft start modules with check valve functions are installed in the main supply lines. The controlled rise attenuates pressure waves, and sensitive measuring devices remain within their permissible pressure rise limits. Result: Extended service life of filters and transducers, more stable process values.

Installation, Adjustment, and Maintenance

Installation should preferably be close to the component to be protected to minimize pressure peaks between the throttle and the consumer. In multi-stage supplies, soft start fittings should be installed in hierarchical order: coarse regulation on the main channel, finer regulation near critical consumers. Adjustment is made by turning the adjustment spindle to the desired stop; calibration using a manometer and gradual load application ensures the desired pressure rise. Maintenance includes regular inspection of seals, lubrication of moving parts (depending on material), and checking for leaks during nominal operation. Polymer versions require periodic visual inspections for cracking under chemical stress. Spare parts such as O-rings and springs should be available in the spare parts warehouse to minimize downtime.

Compatibility and Selection Criteria

Selection depends on medium, pressure range, temperature, flow rate, and connection type. For oil environments and higher temperature ranges, nickel-plated brass soft start fittings with FKM seals are preferable. For corrosive or electrically insulating requirements, variants made of polymer with EPDM or NBR seals are suitable. For retrofit projects, thread and hose standards must be observed; compatible adapters reduce conversion effort. For applications with cyclic loads, durable internal materials (stainless steel/hardened steel) and easily accessible adjustment mechanisms should be considered.

Standards, Safety, and Testing Requirements

Soft start fittings must pass leak tests and pressure tests according to relevant standards. In safety-relevant systems, they must be integrated into safety concepts as part of the compressed air system. Documentation of adjustment parameters, test protocols, and material certificates must be kept available for audit and certification processes. When used in potentially explosive atmospheres, additional approvals and the avoidance of electrostatic charging in polymer parts must be considered.

Further technical information and product data sheets can be found on our technical page: maku-industrie.de/technik. Practical application reports and detailed case studies are available at maku-industrie.de/anwendungsbeispiele.

FAQ

1. Which seal should I choose: NBR, FKM, or EPDM?

Choice depends on medium and temperature: NBR for general compressed air and oil mist environments up to approx. 100 °C, FKM (Viton) for higher temperatures and oil-containing media, EPDM for water, steam, and aggressive cleaning agents. Check chemical compatibility in the specific operating fluid directory.

2. Where is the ideal installation location for a soft start fitting?

Install as close as possible to the consumer to be protected to minimize pressure peaks in the pipeline. In complex networks, first regulate coarsely at the main inflow and fine-tune in critical sub-branches.

3. How do I correctly set the pressure rise rate?

Control with a manometer and gradual load application: Adjust the spindle so that the pressure rise occurs evenly over the desired time span (seconds range). If unsure, perform calibration runs under load and document the setting.