Engine Room Parts
Piping, Valves & Fittings
CuNi, stainless steel, and galvanized marine piping systems with OEM-specification valves
Request QuoteDurable Piping Systems for Marine Engines
Piping, valves, and fittings form the backbone of engine room fluid systems. Mercer Yachting supplies copper-nickel (CuNi), stainless steel, and galvanized pipe in multiple diameters, with premium ball valves, gate valves, check valves, butterfly valves, and solenoid-operated units. Each component is selected for material compatibility, pressure rating, and compliance with maritime approvals for superyachts, cruise ships, and commercial vessels.
What We Supply
Copper-Nickel Pipe
Seawater-resistant piping in 90/10 and 70/30 CuNi for cooling water, ballast, and bilge applications
Stainless Steel Pipe
316L and 304 SS tubing and seamless pipe for fuel, hydraulic, and high-corrosion environments
Galvanized Steel Pipe
Carbon steel pipe with zinc coating for general engine room service and ballast lines
Pipe Fittings & Flanges
Elbows, tees, unions, flanges, plugs in matching materials, welded or threaded
Ball Valves
Full-port and reduced-port ball valves in bronze, stainless, or carbon steel bodies
Gate, Check & Butterfly Valves
Gate valves for isolation, check valves for backflow prevention, butterfly valves for large-diameter lines
Solenoid Operated Valves
2-way and 3-way solenoid pilot-operated or direct-acting valves for automated systems
Pressure Fittings & Adaptors
Compression fittings, JIC, NPT, and BSP adapters for pressure-rated applications
How to Specify
Provide These Details
- Pipe diameter (DN or inches) and nominal thickness
- Material requirement (CuNi 90/10, SS 316L, galvanized, etc.)
- Working pressure rating (bar/PSI) and test pressure
- End connections (threaded NPT/BSP, flanged, welded, compression)
- Approvals needed (ABS, DNV, Lloyds, PED, etc.)
- Valve type and flow direction (for check valves, solenoid configuration)
Common RFQs We Handle
CuNi 90/10 Seamless Tube
Seawater cooling system piping, multiple diameters and wall thicknesses
Stainless 316L Ball Valve
2-piece threaded or flanged ball valve for fuel or high-pressure hydraulic lines
Gate Valve DN100 PN16
Main engine cooling or ballast line isolation valve
Solenoid Pilot-Operated Valve
Automated fuel oil transfer or cooling water isolation
Check Valve Spring-Loaded
Backflow prevention for fuel, fresh water, or hydraulic systems
CuNi Flange Weld Neck
Seawater pump discharge or heat exchanger connection
Butterfly Valve DN200 CW617N
Fuel oil or cooling water large-bore main line isolation
Bronze Ball Valve NPT Threaded
Auxiliary small-bore fuel or drain line shutoff
Stainless Compression Fitting Kit
316L SS tube connections with ferrules and nuts
Galvanized Elbow Welded
90-degree elbows for ballast or general engine room piping
Ball Valve with Locknut
Stainless steel isolation valve with anti-rotation locking mechanism
Solenoid 2-Way Fuel Valve
Automatic fuel cutoff for emergency shutdown systems
Pipe Tee Fitting DN50
Stainless or CuNi equal or reducing tees for system branching
Union Fitting Compression
Quick-disconnect 316L SS unions for maintenance accessibility
Pilot-Operated Check Valve
Allows flow reversal under pilot signal for pump circulation
Frequently Asked Questions
Why is copper-nickel preferred for seawater piping?
CuNi 90/10 and 70/30 alloys provide superior corrosion resistance in seawater environments without galvanic corrosion. They also resist biofouling and require minimal inhibitor treatment, making them ideal for cooling water and ballast lines on marine vessels.
What is the difference between ANSI and DIN pressure ratings?
ANSI (American National Standards Institute) uses psi and flange classes (150, 300, 600), while DIN (German standard) uses bar and PN designations (PN10, PN16, PN25). Always match the pressure rating to your actual system working pressure plus a safety margin.
Can stainless steel valves be used interchangeably with bronze?
Yes, in compatible applications. Stainless steel (316L) offers superior corrosion resistance and strength but is more expensive. Bronze works well in non-critical applications. Avoid mixing materials in the same line due to galvanic corrosion risk.
What is a full-port ball valve?
A full-port ball valve has an internal ball with a bore diameter matching the pipe size, minimizing pressure drop and resistance to flow. Reduced-port valves have a smaller bore and are acceptable in non-critical applications where some pressure loss is acceptable.
How do solenoid-operated valves differ from manual ball valves?
Solenoid valves are electrically actuated and can be automated or remote-operated, ideal for emergency shutdowns and system control. Manual ball valves require physical actuation. Solenoids are faster but more complex and require electrical supply.
What approvals are required for marine piping systems?
Major approvals include ABS (American Bureau of Shipping), DNV (Det Norske Veritas), Lloyds, and RINA. Approvals vary by vessel flag and purpose. PED (Pressure Equipment Directive) applies to EU-manufactured equipment. Always specify required approvals when ordering.
Can copper-nickel pipe be welded?
Yes, CuNi can be welded using TIG or MIG processes with proper filler material and post-weld heat treatment. However, seamless or brazed connections are often preferred to avoid weld brittleness and corrosion issues in high-velocity seawater service.
What is a check valve and when is it needed?
A check valve allows flow in one direction and blocks reverse flow automatically, preventing backflow and cross-contamination. They're essential on pump discharge lines, between fuel tanks, and wherever system pressure could reverse.
Delivery Footprint
Mercer Yachting delivers across the Mediterranean — Malta, Antibes, Palma de Mallorca, Barcelona, Genoa, Athens, Split — and worldwide via our global logistics network. Emergency parts dispatched same-day from our Malta hub.
Ready to Specify Piping & Valves?
Our engine room specialists can source OEM-specification piping, valves, and fittings for any marine application. Contact us with your vessel type, system requirements, and approvals needed for a rapid quote.