6831-6831K

Summary

Product identification

The CAT Pumps Models 6831 (Standard) and 6831K (Flushed) are 68 Frame Block-Style Stainless Steel Triplex Plunger Pumps.

Key features include:

• Triplex plunger design for high efficiency and low pulsation.
• Durable dual V-Packings, lubricated and cooled by pumped liquid.
• Pre-Set Lo-Pressure seals for secondary protection against external leaks, requiring no packing adjustment.
• Special high-density, polished, concentric ceramic plungers for a true wear surface and extended seal life.
• Specially formulated seals and V-Packings for unmatched performance and seal life.
• Wet-end is easily serviced without entering the crankcase.
• Dipstick offers top access for easy oil level check.
• Manifolds are 316 SS block-style for long-term, continuous-duty and corrosion resistance.
• 316 stainless steel valves, seats, and springs provide corrosion-resistance, ultimate seating, and extended life.

Flushed "K" Models feature a special ported inlet manifold that permits an external flush liquid for cooling with high-temperature liquids and lubrication with low-lubricity liquids.

Operating limits

• Flow: 40 gpm (151 l/m)
• Pressure Range: 100 to 2300 psi (7 to 160 bar)
• Inlet Pressure Range: Flooded to 50 psi (Flooded to 3.5 bar)
• Max. RPM: 625 rpm
• Maximum Liquid Temperature: 140°F (60°C)
  • Note: Above 130°F, contact Cat Pumps for inlet conditions and elastomer recommendations.
• Crankcase Capacity: 10 Qts. (9.46 l)

Feed water

Standard models' Lo-Pressure Seals and V-Packings are lubricated and cooled by the pumped liquid. Flushed models (6831K) allow for an external flush liquid to provide additional cooling for high-temperature liquids and lubrication for low-lubricity liquids.

A C.A.T. (Inlet pressure stabilizer) is highly recommended for pressurized inlet, R.O., and industrial applications.

Electrical

Electric Horsepower Requirements

Formulas for Drive Calculations:

• Determining the Pump R.P.M.: Rated gpm / Rated rpm = “Desired” gpm / “Desired” rpm
• Determining the Required H.P.: gpm x psi / 1460 = H. P. Required
• Determining Motor Pulley Size: Motor Pulley O.D. / Pump rpm = Pump Pulley O.D. / Motor rpm

Mechanical / hydraulic

• Bore: 1.575" (40 mm)
• Stroke: 2.579" (65.5 mm)
• Inlet Ports (2): 1-1/2" NPTF
• Flushing Ports (2): 1/2" NPTF (for K Models)
• Discharge Ports (2): 1" NPTF
• Shaft Diameter: 1.772" (45 mm)
• Weight: 355 lbs. (161 kg)
• Dimensions: 29.5 x 24.33 x 12.00" (750 x 618 x 305 mm)

Parts list

A detailed parts list is available, specifying components for both 6831 (Standard) and 6831K (Flushed) models, including materials like Stainless Steel, Aluminum, Ceramic, and various elastomers (NBR, FPM, PTFE, PVDF). Seal and Valve Kits are also listed. See the official PDF for exact tabulated values.

Safety information

All High Pressure Systems require a primary pressure regulating device (e.g., regulator, unloader) and a secondary pressure relief device (e.g., pop-off valve, relief valve). Failure to install such relief devices could result in personal injury or damage to the pump or property. CAT PUMPS does not assume any liability or responsibility for the operation of a customer’s high-pressure system.

Read all CAUTIONS and WARNINGS before commencing service or operation of any high-pressure system. These are included in each service manual and with each Accessory Data sheet.

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Disclaimer: This summary is based on extracted text and may not include all figures, footnotes, or the latest revisions from the complete OEM PDF datasheet. Contractual data must always match the specific OEM PDF revision used on the project.

Official datasheet (PDF)

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