Model L12-TL

Long Pan Thief Hatch

The L12-TL incorporates a large working surface, larger cover and a gauging and sampling hook into the base. The base is inclined to match the slope of the API 12 tank’s roof to provide a level working surface.

The L12-TL outperforms the competition with industry-leading flow rates and high-precision tolerances for a superior seal. A leakage rate less than 1 SCFH of air at 90% of set pressure keeps your tanks in compliance with industry standards.

Thief hatches are used on steel or fiberglass (FRP) low-pressure oil tanks to provide access for level gauging, sampling and overpressure or vacuum protection, all in one compact design.

  • Long pan contains product loss during sampling
  • Ultra-tight sealing reduces product leakage and fugitive emissions
  • Higher flow capacity prevents excessive pressure buildup
  • Easily maintained, reducing downtime and lowering operational costs
  • Corrosion resistance can be enhanced with FKM soft goods and coating
  • Direct replacement for any standard round API 12 thief hatch
    We supply adapters for other sizes. Contact us for details.
  • Incorporates a mechanical lock system to be used with a padlock or lockout bar
  • Bonding strap comes standard

Size: 8″ (200 mm)

Bolting: API 12

Available pressure settings: 4, 6, 8, 10, 12, 16, 24, 32 osig

Additional pressure settings are available. Contact us for more information.

Available vacuum settings: 0.4, 0.9, 3.5 osig

Casting: Aluminum (non-sparking)

Envelope gasket: HNBR, FKM or fluorosilicone

Vacuum diaphragm: HNBR, FKM, fluorosilicone or fluoropolymer

Leak rate: Less than 1 SCFH air @ 90% of set pressure

in mm
8 200
A (Closed) D (Open)
in mm in mm
15.52 394 19.92 506
B (Closed) C (Open)
in mm in mm
8.08 205 15.33 389
E (Open)
deg lbs kg
112.6 19.5 8.86

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