Product Overview

Model 16-501
Adjustable relief valves protect equipment by providing low volume liquid relief or
bypass control. Excess volume may be discharged back to the low pressure source.
Ideal for agricultural sprayers and simple commercial or industrial
pressurized systems.
Features
• Adjustable relief settings, in two ranges to 600 psi
• Cast bronze body, stainless steel springs
• Choice of Nitrile (Buna) or PTFE soft seats
• Knurled locknut locks pressure adjustment
• Viton stem seal, polypropylene body gasket
• Maximum recommended service temperature 200˚F
Models 16-503 and 16-504
Calibrated pressure relief valve allows for in-line pressure adjustments without the
need for a pressure gauge. Provides static overpressure protection for liquid filled
systems such as well pumps, tanks, fire protection systems.
Features
• Choice of 1/2" or 3/4" inlet connection
• Factory preset at 100 psi
• Pressure range 50 to 175 psi, calibrated in 25 psi increments
• Cast bronze body, stainless steel spring
• Silicone soft seat, EPDM cap seal
• Maximum recommended service temperature 200˚F
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16-501, 16-503, 16-504
General Purpose Pressure Relief Valves
Dimensions and Weights
Model Inlet Relief Seat Dimensions (in./mm.) Wt./100
Number Size (in./mm.) Range Material A B C (lbs./kg.)
16-501-01 50 - 250 Nitrile
16-501-02 1/2 M X 1/2 F 250 - 600 1.29 4.12 1.00 62
16-501-25 15 M x 15 F 50 - 250 PTFE 33 105 25 28
16-501-60 250 - 600
16-501
16-503
16-504
A
B
C
C
A
B
Dimensions and Weights
Model Inlet Dimensions (in./mm.) Wt./100
Number Size (in./mm.) A B C (lbs./kg.)
16-503-01 1/2 M X 1/2 F
15 M x 15 F 1.31 3.44 1.00 37
16-504-01 3/4 M X 1/2 F 33 87 25 17
20 M x 15 F