Product ID: 49884562 – Spring, LP Water Inlet (Inlet Check Valve Compression Spring)

Description:
This component is a low-pressure (LP) water inlet compression spring, specifically designed for the inlet check valve assembly within the sealing head of high-pressure waterjet intensifier pumps . It is a precision-wound helical spring manufactured from stainless steel wire, engineered to provide consistent closing force for the inlet poppet valve . The spring ensures that the inlet check valve closes reliably after each intake stroke, preventing backflow of high-pressure water into the low-pressure water supply line. This component is rated for continuous operation at 60,000 PSI (approximately 4,137 bar) .

Applications:

• Used as the return spring for the inlet check valve poppet within the sealing head assembly of waterjet intensifier pumps 

• Installed in the low-pressure water inlet side of the check valve assembly, positioned behind the inlet poppet

• Suitable for ultra-high pressure waterjet systems operating at 60,000 PSI (approximately 4,137 bar)

• Compatible with Streamline SL-IV, PRO-III, Neoline series intensifier pumps, and other .875 inch (7/8") plunger systems 

• Specifically utilized on early Neoline units with washer-style inlet poppet design 

Features:

• Stainless Steel Construction: Manufactured from corrosion-resistant stainless steel wire, providing excellent elasticity, fatigue resistance, and durability in waterjet environments 

• Precision-Wound Design: CNC-formed and heat-treated for dimensional accuracy, consistent spring rate, and long service life under continuous high-cycle operation

• Low-Pressure Rating: Specifically engineered for the low-pressure (LP) water inlet side of the check valve assembly

• Lightweight: Product weight of approximately 0.001 kg (1 gram) for easy handling during maintenance 

• Compression Spring Configuration: Helical spring designed to work in compression, pushing the inlet poppet against its seat to maintain a closed position when the intensifier is not in the intake stroke 

• OEM Compatibility: Direct replacement part for KMT AccuStream waterjet systems 

• Cross-Reference Part Numbers: Replaces or cross-references with 1-11329, 5000056, SL49884562, and 103392 

Maintenance:

• Critical Wear Component: The inlet compression spring is a consumable part that undergoes constant compression and decompression cycles. Fatigue or loss of tension will affect valve responsiveness and proper seating of the inlet poppet

• Inspection: During sealing head or check valve overhaul, inspect the spring for signs of fatigue, breakage, corrosion, or loss of tension. Compare its free length to manufacturer specifications. Even minor deformation warrants replacement

• Replacement Criteria: Replace the spring if any visible deformation, cracking, loss of spring force, or corrosion is detected. A weak spring may cause delayed valve closing, pressure fluctuations, incomplete sealing, or water hammer effects

• Set Replacement: When servicing the inlet check valve, it is recommended to replace the inlet compression spring simultaneously with the inlet poppet as a complete set . Reusing an old spring with new poppet components may result in improper seating force

• Full Depressurization: Always fully depressurize the waterjet system (both hydraulic and high-pressure water circuits) and follow lockout/tagout procedures before removing the sealing head assembly or replacing the inlet spring

• Cleaning: Before installation, ensure the spring and the spring cavity in the sealing head are clean and free from debris, mineral deposits, or old seal residue

• Lubrication: Apply a light coating of manufacturer-recommended high-pressure grease or assembly lubricant to the spring ends during reassembly to prevent corrosion and ensure smooth operation

• Kit Availability: This compression spring is included as a component in high-pressure check valve repair kits for .875 plunger intensifier pumps, which include the spring, inlet poppet, outlet poppet, seat, and poppet pin for a complete valve overhaul 

• Storage: Store spare springs in a clean, dry environment away from direct sunlight, ozone, or harsh chemicals to prevent material degradation

• Water Quality Impact: Poor water quality (contaminants, scale, hardness) can accelerate corrosion or fouling of the spring, affecting its performance and service life. Proper water filtration and treatment are recommended