Product Name: Rebuild Kit, Hydraulic Seal Assembly (Low Pressure Seal Kit) – Part No. 20458797

Description:
This component is a Low Pressure (Hydraulic) Seal Rebuild Kit, specifically designed for the hydraulic (low-pressure) side of a waterjet intensifier pump . It is a comprehensive set of consumable sealing components used to rebuild the hydraulic cylinder assembly, preventing leaks of hydraulic fluid and ensuring the smooth reciprocating motion of the intensifier piston.

The kit is listed as Item 9 in the Intensifier Assembly 20458728 parts diagram . It contains all the necessary O-rings, rod seals, backup rings, and wipers required to service the hydraulic end of the pump. This kit is designed for the standard "Low Pressure" section of the intensifier, distinguishing it from the High Pressure (HP) Seal Kit used for the water side.

Applications:

• Rebuilds the hydraulic cylinder and End Bell assemblies in waterjet intensifier pumps .

• Seals the interface between the hydraulic piston rod and the cylinder, preventing external oil leakage .

• Used during scheduled Major Maintenance, Minor Maintenance, or complete pump overhauls .

• Suitable for 60,000-94,000 PSI (approximately 4,137-6,480 bar) waterjet intensifier systems .

Features:

• Complete Kit: Contains all seals, O-rings, spacers, and snap rings necessary for a full hydraulic seal rebuild .

• High Durability: Components are manufactured from wear-resistant materials designed to withstand millions of high-cycle pressure strokes .

• Oil Compatibility: Seal materials are specifically formulated for resistance to petroleum-based hydraulic fluids and extreme pressure additives.

• Critical Maintenance Component: Essential for stopping hydraulic oil leaks (weeping) from the pump cylinder or end bell joints .

• Direct OEM Replacement: Interchangeable with part numbers 302007-3, 106923, and OEM 20458797 .

Maintenance:

When to Replace (Failure Diagnosis):

• External Hydraulic Leakage: Visible oil weeping from the joint between the End Bell and the Hydraulic Cylinder indicates rod seal failure .

• Fluid Level Drop: A sudden or consistent drop in the hydraulic reservoir oil level without visible external leaks suggests internal seal bypass.

• Erratic Intensifier Cycling: The pump may cycle irregularly, overstroke, or fail to build full cutting pressure due to worn piston seals .

• Scheduled Overhaul: It is standard practice to replace the Low Pressure Seal Kit during major pump maintenance intervals (e.g., every 2,000-5,000 hours) to prevent unexpected downtime.

Inspection and Replacement Guidelines:

• Full Depressurization (Critical): Before any maintenance, place the main electrical disconnect in the OFF position, bleed down all high-pressure lines, fully depressurize the hydraulic system, and follow lockout/tagout procedures.

• Disassembly:

1. Remove the End Caps and High Pressure Cylinders .

2. Remove the tie rod nuts and tie rods.

3. Remove the End Bells from the hydraulic cylinder .

4. Remove the snap ring, spacer, and old oil seals from the End Bell interior .

• Clean Area Maintenance: Perform the rebuild in a designated clean area. Thoroughly clean the cylinder bore, End Bell cavity, and all sealing surfaces with a lint-free cloth.

• Lubrication: Lubricate all new seals (O-rings, rod seals) with clean hydraulic oil or high-pressure grease (e.g., P/N 400015-1) during installation to prevent dry start-up and pinching.

• Installation (Rod Seal): When installing new rod seals into the End Bell, ensure the sealing lip faces the pressure source (the inside of the hydraulic cylinder). Use a seal installation sleeve to prevent the threads from cutting the new seal.

• Installation (Piston Seals): If servicing the hydraulic piston, note that the center band consists of an inner Energizer Ring and an outer Teflon Cap Ring. Heating the Teflon Cap Ring in 150°-200°F (65°-90°C) water for 2-3 minutes will soften it, facilitating installation. The cap must be resized using a ring compressor for at least three minutes so it will fit in the hydraulic cylinder bore .

• Reassembly (Critical):

• An intensifier assembly fixture must be used to square the End Bells with each other during reassembly. If End Bells are assembled out of alignment, oil manifold leakage and breakage may occur .

• Tighten the tie rod nuts in a crossing (staggered) pattern to the specific torque value listed in the equipment service manual (e.g., 160 Nm / 120 ft-lbs) .