Model L12-TH

Round Pan Thief Hatch

The LaMOT Valve & Arrestor Model L12-TH Thief Hatch incorporates a spring loaded pressure/vacuum relief valve within the device. Thief Hatches are used on steel or fiberglass (FRP) low pressure storage tanks. The hatch has a gauging hook integrated to the base to be used while sampling the tank, providing access for level gauging, sampling, and overpressure/vacuum protection for the tanks, all in one compact design. Superior sealing is achieved from an active envelope pressure gasket that expands around the base to increase seal until the designated pressure setting is reached. This design saves you money by greatly reducing vapor loss compared to a traditional thief hatch design.

• Each Hatch is individually tested and certified at factory

• Each hatch has its own serial number – for tracking and traceability

• Precision machining and manufacturing to accomplish superior sealing

• Leak Rate less than 1.0 SCFH at 90% of set pressure

• Ultra-tight sealing reduces product leakage and fugitive emissions

• Industry leading flow rates

• Higher flow capacity to protect from excessive pressure build up

• Precision machining and manufacturing to accomplish high flow rates

• Active envelope pressure gasket that expands around the base to increase seal

• Three Ear Center Assembly – better alignment and stronger, less breakage

• Pressure gasket is captured in the center assembly by groove

• SLIC Pins used on lid hinge, latch hinge and latch lock pin – less time for maintenance

• Rear hinge is precision machined – provides superior alignment and sealing

• Incorporates a mechanical lock system to be used with a pad lock or lock out bar

• Bonding Strap is standard equipment

• L12-TH convertible to a Lockdown Hatch with LVA conversion kit (L-Kit)

• Superior emission performance validated by End User FLIR inspection

• *Optional Thrust Bearing (Must be ordered with “Hatch” or “Center Assembly” for in the field replacement)

• Size: 8”

• Bolting: API 12

• Available Pressure Settings: 4, 6, 8, 10, 12, 16, 24, & 32 osig

• Available Vacuum Settings: 0.4. 0.9 & 3.5 osig

• Leak Rate: Less than 1 SCFH of Air @ 90% of Set Pressure

• Casting: Aluminum (non-sparking)

• Envelope Gasket: HNBR, FKM or Fluorosilicone

• Vacuum Diaphragm: HNBR, FKM, Fluorosilicone or Fluoropolymer

• Springs: Galvanized Steel or Inconel® X-750

• Polyester/PTFE Coating

• Flange (base) Gasket

• Mounting Kit

• Adapters

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Envelope Gasket

Vacuum Diaphragm

Spring Material

Pressure Setting

Vacuum Setting


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