Pipe routing

Pipe routing describes the planned arrangement, fastening, and guidance of lines for liquids and gases in machines, structures, and on construction sites. In the application areas of concrete demolition and special demolition, gutting works and cutting as well as rock excavation and tunnel construction, precise pipe routing determines operational safety, performance, and maintainability. This applies in particular to hydraulic systems in which hydraulic power packs supply tools such as concrete demolition shears or hydraulic wedge splitters via lines. Proper routing minimizes pressure drops and pulsations, reduces mechanical risk from abrasion and impacts, and shortens set-up and service times across temporary and permanent installations.

Definition: What is meant by pipe routing?

Pipe routing (also line routing or piping routing) comprises all measures for defining the pipe run, support spans, supports/clamps, expansion concepts, and the interfaces to power packs and consumers. The objective is a flow-optimized, safe, and accessible routing that takes into account media, pressure ranges, temperature, vibrations, installation and maintenance requirements, and environmental conditions. This also includes flexible hose sections in hydraulic systems when movements must be accommodated or vibrations decoupled. In practice, pipe routing covers the full lifecycle from concept and isometrics to installation, documentation, and later modification, including clear interface management to manifolds, power packs, and tools.

Technical fundamentals of pipe routing

Professional pipe routing is based on medium, pressure rating, temperature, environment, and mechanical loading. Essential parameters are bend radius, flow velocity, pressure loss, vibration excitation, elongation, and thermal expansion. Fixed points, sliding supports, and expansion compensators define where lines may move and where forces are introduced into the structure. Media-compatible materials, tight connection systems, and a corrosion protection-oriented design ensure the durability of the installation. Rules of thumb for hydraulics include low flow velocities in suction lines, moderate velocities in return lines, and higher but controlled velocities in pressure lines, while elbows and fittings must be counted as equivalent lengths when estimating pressure loss.

Pipe routing in hydraulic systems of concrete demolition shears and hydraulic wedge splitters

Hydraulic drives connect hydraulic power packs to the tools via lines. For concrete demolition shears and hydraulic wedge splitters, short, protected, and flow-optimized runs are crucial to ensure response times, force development, and energy efficiency. Pulsation-sensitive sections near actuators benefit from minimal internal volume and a reduced number of joints.

Bend radii, flow, and pressure losses

• Observe minimum radii: Bends that are too tight increase pressure loss, heat the oil, and stress the lines. The manufacturers’ minimum bend radii must be observed.
• Select an appropriate cross-section: Dimension for the required flow rate. Diameters that are too small increase flow velocity and promote erosion and cavitation.
• Execute transitions with good flow characteristics: Use gentle transitions for reductions and branches to reduce turbulence and pressure surges.
• Minimize fittings and sharp elbows: Prefer swept bends and smooth radius components to reduce local losses and noise.
• Provide straight inlet and outlet lengths: Keep sufficient straight runs upstream and downstream of pumps, valves, and flow meters to stabilize the flow.

Vibrations, movements, and protection

• Vibration decoupling: Provide flexible hose sections between rigidly piped sections and moving components.
• Abrasion and kink protection: Use protective sleeves and clamps with inserts. Do not route lines over sharp edges.
• Movement reserves: Route lines with sufficient length and suitable loops so that lifting and slewing movements can be accommodated without building up torsion.
• Two-point clamping near masses: Support heavy fittings and valves close to the center of mass to avoid oscillation and fatigue.
• Prevent hose twist: Align laylines and use swivel fittings where appropriate; avoid torsion during assembly.

Connection points and maintainability

• Arrange quick couplers accessibly: Position coupling points so that rapid tool changes are possible and contamination is avoided.
• Identification: Clearly mark pressure and return lines; avoid mix-ups.
• Control leakage paths: Route drip points away from hot surfaces and electrical equipment.
• Use contamination control measures: Provide dust caps and parking stations for uncoupled lines; keep sealing faces protected.
• Design for service space: Ensure clearance for spanners and torque tools and enable safe depressurization before disconnection.

Pipe routing in concrete demolition, rock excavation, and tunnel construction

In harsh environments, lines must be protected against abrasion, impacts, moisture, and dirt. In tunnel and rock zones, pipe routing must be planned particularly compactly to account for constrictions, limited visibility, and changing load cases, as in rock demolition and tunnel construction. Shielding, compact routing corridors, and clear separation between hydraulic and auxiliary media lines increase operational robustness.

• Protection against rockfall: Route lines behind structural protective plates or within robust pipe routes.
• Avoid tripping and snagging points: Avoid free-hanging lines; provide clear routes above head height or near the floor in protective channels.
• Water and dust management: Route additional media lines (e.g., for dust suppression) so that they do not cross or damage the hydraulic lines.
• Observe temperature zones: Keep distance from exhaust systems and hot surfaces; use heat protection sleeves where required.
• Plan for inspection and cleaning: Integrate accessible sections and drains so that mud and debris cannot accumulate around clamps and guards.

Fastening, support, and expansion compensation

The fastening strategy is decisive for vibration behavior, noise development, and service life. Properly placed fixed points and sliding supports prevent restraint forces. Expansion paths must be predictable, with loads transferred into sufficiently stiff structures.

• Support spans: Match support spacing to pipe diameter, weight, and dynamics; use closer spacing on vertical routes.
• Fixed and sliding points: Place fixed points on robust structures; low-friction sliding supports allow longitudinal expansion.
• Expansion compensators: Use compensators, U-loops, or Z-bends to accommodate thermal expansion.
• Avoid mixed clamps for dissimilar lines: Do not bind hoses and rigid pipes in a common clamp; assign dedicated supports.
• Respect structural joints: Do not bridge expansion joints or detachable frames with rigid lines without suitable compensation elements.

Materials, connection technology, and corrosion protection

The choice of materials depends on medium, temperature, pressure, and environment. In demolition environments, resistance to moisture, dust, and chemical influences is crucial. Media compatibility with biodegradable hydraulic fluids and additives must be ensured for seals, hoses, and coatings.

• Pipes and hose materials: Steel, stainless steel, or coated pipes for rigid routes; hydraulic hoses with suitable pressure class and abrasion resistance for moving zones.
• Connections: Cutting-ring fittings, flange joints, or suitable threaded connections with media-compatible seals; clean, stress-free installation.
• Corrosion protection: Provide coatings, stainless steels, and drainage points; avoid galvanic corrosion.
• Joint reduction in high-vibration areas: Prefer welded spools and integral manifolds where feasible to reduce potential leakage points.
• Electrical isolation where needed: Use insulating bushings or clamps between dissimilar metals to mitigate galvanic couples.

Assembly, commissioning, and testing of pipe routing

Quality is created during assembly. Careful preparation, clean working practices, and documented tests ensure proper function. Verification should include cleanliness, pressure integrity, and functional behavior under representative load cycles.

1. Prefabrication and trial fit: Check isometrics, label components, simulate installation position.
2. Cleanliness: Keep chips, dust, and moisture away; keep ends closed until installation.
3. Alignment: Install free of stress; check alignment of flanges and fittings.
4. Flushing and filtration: Flush lines, check filters to protect the power pack and tools.
5. Pressure and leakage test: Perform according to applicable rules; document the results.
6. Functional test: Observe temperature, noises, vibrations, pressure level, and cycle times; then retighten connections as specified.
7. Torque and marking: Tighten to specified torque; apply witness marks to detect loosening during early operation.
8. Cleanliness validation: Achieve the agreed target cleanliness class and verify with a suitable particle check before handover.

Safety, environmental, and fire protection aspects of pipe routing

Safety and environmental protection are integral parts of pipe routing. The following points are proven principles that must be adapted to the specific framework conditions. Secondary containment, safe depressurization, and controlled media handling reduce residual risk.

• Avoid leakages: Double-secure stressed zones; provide containment; dispose of media properly.
• Fire protection: Seal penetrations correctly using fire stop (sealing); spatially separate flammable media and route them away from ignition sources.
• Signage and accessibility: Arrange shut-off devices so they are reachable; keep escape and rescue routes clear.
• Pressure surge management: Use soft start-up and suitable damping elements; avoid abrupt valve closures.
• Overpressure protection: Place relief devices close to sources and direct return lines safely to tank or collection points.
• Spill preparedness: Provide absorbents and drip trays at maintenance points; define emergency procedures for hose or pipe failure.

Typical failure patterns and how to avoid them

• Bend radii too tight: Lead to kinking, heating, and performance loss. Consistently observe minimum bend radii.
• Insufficient fastening: Vibrations cause leakages. Reduce support spacing and improve clamp quality.
• Collisions and chafe points: Plan routes to be collision-free, provide protection at contact points.
• Incorrect hose lengths: Hoses that are too short tear during movement, overly long hoses form loops. Determine lengths within the working range.
• Unclear identification: Avoid mix-ups at connection points; use color and text marking.
• Hose twist during assembly: Visible spiral laylines indicate torsion; correct alignment and use swivels to prevent fatigue failure.
• Unsupported masses at fittings: Heavy couplers or valves need nearby supports to prevent bending moments and micro-movements.
• Overtightened fittings: Excess torque damages seats and seals; follow specified torque values.

Pipe routing for mobile hydraulic power packs and special operations

With mobile hydraulic power packs, lines often have to be routed, secured, and redeployed quickly. In special operations, for example when working with a cutting torch, steel shears, combination shears, or multi cutters, additional media and safety requirements apply. Routing concepts must also withstand frequent coupling cycles and transport-induced vibrations.

• Modular routes: Plug-in and clamping systems for quick changes; nevertheless secured against tension and torsion.
• Transport condition: Fix lines relieved of load, cap ends to prevent contamination.
• Interface management: Clear assignment between power pack and tool; do not swap pressure and return.
• Additional media: For thermal or fire-sensitive work, route media lines separately and protected.
• Strain relief and parking: Use strain-relief points and defined parking stations for hoses and couplers to prevent damage in transit.

Retrofit, deconstruction, and dismantling of pipelines

In gutting works and cutting environments, lines are frequently rerouted or removed. An orderly approach prevents consequential damage and shortens downtimes. Defined responsibilities, labeling, and interim protection for remaining lines are key.

• Systematically drain and depressurize: Prevent hazards; collect residual quantities.
• Define deconstruction sequence: From peripheral to central; release fixed and sliding points without unintentionally freeing loads.
• Update documentation: Continue piping plans, markings, and test protocols to facilitate later reassembly.
• Lockout-tagout: Secure energy sources and verify zero pressure using gauges before opening any line.
• Seal open interfaces: Use labeled caps or blinds to exclude dirt ingress and cross-contamination during temporary states.

Practice checklist for pipe routing

1. Define medium, pressure, temperature, and environment.
2. Specify the routing with fixed points, sliding supports, and expansion compensation.
3. Dimension cross-sections and bend radii for proper flow.
4. Decouple vibrations, provide abrasion protection.
5. Arrange switching and coupling points to be accessible and clearly identified.
6. Integrate corrosion protection and fire protection measures.
7. Assemble cleanly, free of stress, followed by flushing and testing.
8. In operation: Monitor temperatures, noises, leakages, and cycles; retighten.
9. Document as-built routing, identification, and test results; maintain revision control.
10. Define inspection intervals and replacement criteria for hoses, clamps, and seals.