U-cup Seal 202398
Product Name: U-Cup Seal (Part No. 202398)
Description:
The U-Cup Seal 202398 is a single-acting, pressure-energized dynamic sealing component specifically engineered for the coolant housing and hydraulic circuit of ultra-high-pressure waterjet intensifier pumps . It is manufactured from premium-grade polyurethane or a PTFE-reinforced composite, chosen for its high abrasion resistance, elasticity, and structural integrity under extreme pressure cycling .
Characterized by its distinctive "U" shaped lip profile, this seal is designed to be self-energizing. Under operating pressure, the lips of the "U" expand outward against the sealing surfaces, creating a tighter, more effective seal as system pressure increases . This design significantly reduces friction between moving parts (such as the plunger and cylinder wall) compared to traditional O-rings, which helps extend the lifespan of both the seal and the mechanical components it protects .
This component is critical for maintaining the separation between the hydraulic oil system and the high-pressure water section of the pump, preventing fluid bypass and ensuring consistent pressure delivery to the cutting head. It is a standard "Replace" item during Minor Maintenance, Major Maintenance, and Complete Overhaul procedures according to OEM service documentation .
Applications:
Seals the coolant housing and hydraulic circuits in waterjet intensifier pumps
Provides a dynamic seal between the reciprocating plunger and cylinder bore
Suitable for ultra-high pressure waterjet systems operating at 60,000 PSI (4,137 bar) and above
Compatible with OMAX EnduroMAX, OMAX Maxiem, KMT, FLOW, WSI, and BFT waterjet systems
Features:
Self-Energizing U-Shape Lip: Expands under pressure to provide a tighter seal as system pressure increases, ensuring leak-proof operation under extreme conditions
Premium Material: Manufactured from high-strength polyurethane or PTFE composite, offering excellent resistance to extrusion, abrasion, and hydraulic fluid degradation
Low Friction Design: Unique lip geometry reduces friction between the seal and the reciprocating plunger, minimizing wear on both components
High-Pressure Rating: Engineered for continuous operation at up to 60,000 PSI (4,100 bar) with a temperature range of -30°C to +120°C
OEM Specification: Direct OEM replacement for OMAX 202398, AccuStream 1-11993, and WSI MX202398
Weight: Approximately 0.001 lbs for easy handling during maintenance
Maintenance:
Failure Diagnosis:
External Leakage: Visible hydraulic fluid weeping from the coolant housing or pump area indicates U-cup seal failure requiring immediate replacement
Hydraulic Oil Contamination: Milky or discolored hydraulic oil may indicate seal failure allowing water intrusion
Pressure Drop: Inability to maintain rated cutting pressure (typically 30% or more drop) suggests seal wear or lip deformation
Increased Cycling Frequency: More frequent intensifier cycling may indicate internal bypass past a worn seal
Scheduled Replacement: According to OMAX service documentation, the U-cup seal is classified as a "Replace" component during Minor Maintenance, Major Maintenance (every 4,500-5,000 hours), and Overhaul procedures
Replacement Procedures:
Full Depressurization (Critical): Before any maintenance, fully depressurize the waterjet system (high-pressure water, hydraulic system, and air supply) and follow lockout/tagout procedures to prevent severe injury
Clean Room Conditions: Perform seal replacement in a designated clean area to prevent contamination of new seals with abrasive particles. Wear disposable gloves to prevent natural oils from contacting seal materials
Plunger Surface Inspection: Before installing a new U-cup, thoroughly inspect the reciprocating plunger surface for scoring, scratching, pitting, or diameter reduction. A damaged plunger will rapidly destroy new seals
Cylinder Bore Inspection: Inspect the cylinder bore for scoring, pitting, or out-of-round conditions that could compromise seal integrity
Orientation (Critical): The U-cup seal must be installed with the open "U" side facing the pressure source. Improper orientation will result in immediate leakage
Lubrication: Apply a generous amount of manufacturer-recommended high-pressure grease to the seal lips and outer diameter during installation to prevent dry start-up and ensure proper seating
Use Proper Tools: Use manufacturer-specified seal installation tools to avoid rolling, twisting, or damaging the sealing lips during assembly
Complete Seal Replacement: When replacing the U-cup seal, it is recommended to replace all associated O-rings and backup rings in the seal stack simultaneously
Torque Compliance: When reassembling the pump, tighten all retaining components to the specific torque values listed in the equipment service manual
Post-Installation Test: After reassembly, slowly pressurize the system and monitor for external leakage before returning to full cutting operations
Storage: Store spare U-cup seals in a cool, dry environment away from direct sunlight, ozone sources, and chemicals to prevent material degradation before use
Cross-Reference Information:
