*mydirectindustry

Catalogs
THE LEE COMPANY
HIGH PRESSURE 375 PILOT OPERATED CHEK

HIGH PRESSURE 375 PILOT OPERATED CHEK

Product catalog summary

Performance Specifications
- Cracking Pressure: 5 ± 3 psid
- Minimum Pilot Ratio: 3:1
- Piloted Flow Rate: 110 Lohms Maximum
- Leakage in Checked Direction: 1 drop/minute at 5 psid, 1 drop/hour at 1000 - 5000 psid
- Pilot Piston Leakage: 1 drop/minute maximum at 5000 psid
- Nominal System Pressure: Up to 5000 psi
- Nominal Weight: 20 grams
- Valve performance tested on MIL-PRF-83282 at 85°F

Product Overview
The High Pressure 375 Pilot Operated Chek® is designed for system pressures up to 5000 psi. It functions as a normal check valve until pressure is applied to the pilot port, allowing flow in the normally blocked direction. It is suitable for high-pressure hydraulic applications, with a maximum restriction of 110 Lohms when piloted open. The valve is available in forward and reverse free flow configurations and is constructed entirely of stainless steel for durability. Each unit is 100% tested and inspected.

Materials
- Body Front: 304 Cres AMS 5639
- Body Center: 15-5 PH Cres AMS 5659
- Body Rear: 304 Cres AMS 5639
- Springs: 17-7 PH Cres AMS 5678
- Poppet: 15-5 PH Cres AMS 5659
- Pilot Piston: 15-5 PH Cres AMS 5659
- Pin: 17-4 PH Cres AMS 5643
- Compression Seal: Polyimide

Part Numbers and Specifications
- CPRA3757105A: Cracking Pressure 5±3 psid, Minimum Pilot Ratio 3:1, Piloted Lohm Rate 110 Lohms maximum, Flow Direction Reverse
- CPFA3757105A: Cracking Pressure 5±3 psid, Minimum Pilot Ratio 3:1, Piloted Lohm Rate 110 Lohms maximum, Flow Direction Forward

Lohms Laws (Liquids)
The Lohm system defines fluid resistance in hydraulic components, similar to Ohms in electrical systems. A 1 Lohm restriction allows a flow of 100 gallons per minute of water with a pressure drop of 25 psi at 80°F. The system compensates for liquid density and viscosity, applicable to any liquid with known properties.

Liquid Flow Formula
- L = Lohms
- S = Specific gravity
- H = Differential pressure
- V = Viscosity compensation factor
- I = Liquid flow rate: Volumetric
- w = Liquid flow rate: Gravimetric
- K = Units Constant
For specific fluids and temperatures, consult a Lee Sales Engineer or visit the website.

Units Constant K
- Volumetric Flow Units: GPM, L/min, ml/min, in3/min
- Gravimetric Flow Units: PPH, gm/min

Catalog excerpts

PRECISION MICROHYDRAULICS PRODUCT HIGH PRESSURE 375 PILOT OPERATED CHEK® The Lee Company’s new High Pressure 375 Pilot Operated Chek is the latest addition to Lee’s line of miniature check valves. This valve acts like a normal check valve until pressure is applied to the pilot port, which then allows flow in the direction that would normally be blocked. This new valve is ideal for high pressure hydraulic applications with system pressures up to 5000 psi. The maximum restriction when piloted open is only 110 Lohms. The High Pressure 375 Pilot Operated Chek is available in forward and reverse free flow configurations, and the metal components are constructed entirely of stainless steel for durability and long life. Nominal weight is just 20 grams. Each Chek is 100% tested and inspected to ensure reliable, consistent performance. ■ Designed for System Pressures up to 5000 psi ■ 110 Lohms Max. When Piloted Open ■ Weighs Only 20 Grams ■ 100% Tested and Inspected ■ Endurance Tested to 500,000 Cycles ■ No O-Rings PIN Valve performance on MIL-PRF-83282 at 85°F. 1 drop = 50 pL See reverse side for Liquid Lohm Laws. The Lee Company • 2 Pettipaug Road, PO Box 424, Westbrook, Connecticut 06498-0424 Tel: 860-399-6281 • Fax: 860-399-7037 • [email protected] • www.theleeco.com PDS 133 6/15

Open the catalog to page 1

LOHMS LAWS (liquids) Every engineer will be interested in our simple system of defining the fluid resistance of Lee hydraulic components. Just as the OHM is used in the electrical industry, we find that we can use a liquid OHM or "Lohm" to good advantage on all hydraulic computations. When using the Lohm system, you can forget about coefficients of discharge and dimensional tolerances on drilled holes. These factors are automatically compensated for in the Lohm calculations, and confirmed by testing each component to establish flow tolerances. The resistance to flow of any fluid control component...

Open the catalog to page 2

HIGH PRESSURE 375 PILOT OPERATED CHEK

HIGH PRESSURE 375 PILOT OPERATED CHEK

Catalog excerpts

All THE LEE COMPANY catalogs and technical brochures

Archived catalogs