Circle Seal M5120N-4M(L)-ASME ASME Relief Valve
M5100 Series ASME: Popoff Relief Valves 50 to 1200 psig
Features:
- Zero leakage: from 0 psi up to 70% of the marked set pressure
- Manual Override: offered with ring or lift handle
- PED certifications and CE marking available: add “PED” prefix to the valve part number if required
Terminology for ASME Safety Relief Valves:
Safety Relief Valves: An automatic pressure relieving device actuated by the static pressure upstream of the valve, which opens in proportion to the increase over the opening pressure.
Start-to-Leak Pressure: The pressure at the valve inlet where the relieved fluid is first detected (on the downstream side of the seat) before normal relieving action takes place.
Opening Pressure (Set Pressure): The valve inlet pop point pressure at which there is a measurable lift or discharge becomes continuous as determined by seeing, hearing or feeling. In the pop type of safety valve, it is the inlet pressure at which the valve opens, allowing a larger amount of fluid as compared with corresponding valve movements at higher or lower pressures. Note: A safety relief valve is not considered to open when it is simmering at a pressure just below the popping point even though the simmering may be audible. This set pressure distinguishes our ASME relief valves from our standard relief valves whose cracking pressure indicates initial flow.
Relieving Pressure: (Opening pressure plus overpressure) The pressure measured at the valve inlet at which the relieving capacity is determined.
Closing Pressure: (Reseat pressure) The pressure measured at the valve inlet, at which the valve closes, flow is substantially shut off, and there is no measurable lift.
Seal-off Pressure: The pressure (measured at the valve inlet) after closing at which no further gas is detected at the downstream side of the seat.
Operating Pressure: The actual pressure at which a vessel is maintained in normal operation.
Accumulation: Pressure buildup or overpressure beyond the set pressure of a safety relief valve, at which capacity flow is rated. Capacities are usually based on 10% accumulation.
Circle Seal M5120N-4M(L)-ASME Relief Valve Technical Data:
- Description: 1/2″ MNPT Popoff with Manual Override ASME Relief Valve, Naval Brass/PTFE construction, cracking pressures between 50 to 1200 psig
- Configuration: Popoff with Manual Override
- Handle Type: Ring (for cracking pressures up to 450 psig) OR Lift (for cracking pressures above 450 psig)
- Maximum Operating Pressure: 1200 psig
- Body Material: Naval Brass
- Seal Material: PTFE
- Inlet Connection Size & Type: 1/2″ MNPT
- Outlet Connection Size & Type: NONE: DISCHARGE-TO-ATMOSPHERE
- Set Pressure Range: 50 to 1200 psig (REQUIRED SET PRESSURE MUST BE SPECIFIED)
- Temperature: -100F to +300F
Flow Curve:
Dimensional Information:
- Handle Type: Ring (for cracking pressures up to 450 psig) OR Lift (for cracking pressures above 450 psig)
- Length (“E”): 3.86″ (for cracking pressures between 50 and 450 psig)
- Length (“M”): 5.51″ (for cracking pressures between 451 and 1200 psig)
- Hex (“H”): 1.25″
- Diameter (“B”): 1.25″
Recommended Installation:
1. Before installing a new safety relief valve, we recommend that a pipe tap be used to assure clean-cut and uniform threads in the vessel opening and to allow for normal hand engagement followed by a half to one turn by wrench.
2. Avoid over-tightening as this can distort the valve seat.
3. Avoid excess “popping” of the valve. Safety relief valves should only be operated often enough to assure they are in good working order.
4. Apply only a moderate amount of pipe compound or tape to the threads, leaving the first thread clean parts.
5. Don’t oversize the valve, as this may cause chatter resulting in rapid wear of the moving parts.
6. Avoid wire, cable, or chain pulls for attachments to levers that do not allow a vertical pull. The weight of these devices should not be applied to the safety relief valve.
7. Avoid having the operation pressure too near the valve set pressure. A minimum differential of 10% is recommended.
Please contact our Sales Department for assistance in selecting the right products for your application.
Product Catalog: Circle Seal Relief Valves
