Mosmatic 57.153 DYG Rotary Union Swivel – G1 3/8" FPT x G2 3/8" MPT Stainless Steel

Part Number: 57.153
Category: Pressure Washer Parts → Swivels & Fittings
Type: Mosmatic 57.153 DYG Rotary Union Swivel – G3/8" FPT x G3/8" MPT Stainless Steel, Carbide Seal

The Mosmatic 57.153 DYG Rotary Union Swivel is a genuine Mosmatic premium rotary union designed for demanding pressure washing, industrial cleaning, automatic vehicle wash systems, surface cleaners, wash booms, and other high-pressure rotating fluid transfer applications. Featuring G3/8-inch Female BSPP and G3/8-inch Male BSPP threaded connections, this precision-engineered rotary union provides smooth 360-degree continuous rotation while maintaining unrestricted water flow under pressure.

Key Features & Benefits

• Genuine Mosmatic OEM rotary union
• Manufacturer Model: 57.153
• DYG series rotary union
• Premium carbide seal technology
• G3/8" Female BSPP inlet
• G3/8" Male BSPP outlet
• Smooth 360° continuous rotation
• Premium stainless steel construction
• Precision radial and thrust ball bearings
• Maintenance-free design
• Rated for systems up to 5,000 PSI
• Supports rotational speeds up to 2,000 RPM
• Maximum operating temperature: 250°F
• Excellent corrosion resistance
• Designed for continuous-duty commercial and industrial applications

Technical Specifications

Manufacturer: Mosmatic

Manufacturer Model: 57.153

Series: DYG

Product Type: Rotary Union Swivel

Inlet Connection: G3/8" Female BSPP

Outlet Connection: G3/8" Male BSPP

Maximum Working Pressure: 5,000 PSI

Maximum Speed: 2,000 RPM

Maximum Temperature: 250°F

Body Material: Stainless Steel

Seal Material: Tungsten Carbide

Bearing Type: Precision Radial & Thrust Ball Bearings

Swivel Rotation: 360°

OEM Replacement: Yes

Compatible Applications

Suitable for use with:

• Commercial pressure washers
• Industrial pressure washing systems
• Automatic vehicle wash equipment
• Surface cleaners
• Wash booms
• Rotary cleaning equipment
• High-pressure hose reels
• Industrial spray systems
• Manufacturing equipment
• High-pressure fluid transfer systems

Always verify thread type, pressure rating, RPM requirements, and equipment compatibility before ordering. G3/8 BSPP threads are not interchangeable with NPT threads without the appropriate adapters.

Function of the Rotary Union

The Mosmatic 57.153 DYG Rotary Union helps:

• Provide smooth 360° continuous rotation
• Maintain unrestricted high-pressure water flow
• Prevent hose twisting and kinking
• Reduce stress on hoses and plumbing components
• Support high-speed rotating equipment up to 2,000 RPM
• Extend the service life of hoses, reels, and connected equipment

Its tungsten carbide seal and precision bearing system provide outstanding durability and long-term leak-free performance in demanding industrial environments.

Common Signs Replacement Is Needed

Replace the rotary union if you notice:

• Water leaking around the swivel body
• Restricted or rough rotation
• Excessive rotational play
• Damaged or worn threads
• Corrosion or physical damage
• Reduced performance under pressure or high-speed operation

Replacing a worn rotary union restores smooth operation and helps protect connected equipment from premature wear.

Installation & Service Notes

Turn off the pressure washer or equipment and relieve all system pressure before installation.

Verify that both plumbing connections use G3/8 BSPP threads. BSPP fittings typically seal using an O-ring or bonded seal rather than thread interference, so use the appropriate sealing method specified by the equipment manufacturer.

Tighten all threaded connections securely without overtightening.

Verify smooth rotation and inspect the system for leaks before placing the equipment into service.

Important: Never exceed the maximum 5,000 PSI working pressure, 2,000 RPM rotational speed, or 250°F operating temperature. Always verify BSPP thread compatibility before installation.

Maintenance Recommendations

• Inspect the rotary union regularly for leaks and smooth rotation.
• Keep the swivel clean and free of dirt, debris, and mineral buildup.
• Inspect sealing surfaces and bearings during routine maintenance.
• Replace worn seals or damaged internal components promptly.
• Verify proper thread engagement during installation.
• Use only genuine OEM Mosmatic replacement parts to maintain proper fit, reliable performance, and maximum service life.