Model L12-TH

Round Pan Thief Hatch

The Model L12-TH Thief Hatch outperforms the competition with industry-leading flow rates and precision tolerances to provide a superior sealing performance. Leakage rates less than 1 SCFH at 90% of set pressure keeps your tanks industry-standard compliant.

The L12-TH incorporates a spring-loaded pressure/vacuum relief valve within the hatch. Install the L12-TH on steel or fiberglass (FRP) low-pressure oil tanks to provide access for level gauging, sampling and overpressure/vacuum protection, all in one compact design.

  • Ultra-tight sealing reduces product leakage and fugitive emissions
  • Higher flow capacity protects from excessive pressure buildup
  • Easy maintenance for reduced downtime and lower operational costs
  • Optional enhanced corrosion resistance with FKM soft goods and coating
  • Simple, direct replacement for any standard round API 12 thief hatch, with adapters for others – contact us for details
  • Mechanical lock system can be used with a padlock or lockout bar
  • Bonding strap comes standard

Size: 8″ (200 mm)

Bolting: API 12

Pressure settings: 4, 6, 8, 10, 12, 16, 24 and 32 osig*

Vacuum settings: 0.4, 0.9 and 3.5 osig

Casting: aluminum (non-sparking)

Envelope gasket: HNBR, FKM or fluorosilicone

Vacuum diaphragm: HNBR, FKM, fluorosilicone or fluoropolymer

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

Additional pressure settings are available.

in mm
8 200
A (Closed) D (Open)
in mm in mm
14.95 379 20.25 514
B (Closed) C (Open)
in mm in mm
7.45 189 15.25 387
E (Open)
deg lbs kg
109.5 13.8 6.26

Base Gasket:
GKT12TH08K302       =    Non-Asbestos
GKT12TH087602       =    FKM
GKT12TH087102       =    PTFE
GKT12TH084402       =    Black Neoprene
GKT12TH083502       =    Buna-N
GKT12TH08CJ02       =    FKM (Blue)
GKT12TH08BO02      =    Fluorosilicone

Mounting Kit:
KS12THBS08P01       =    Hex Nut and Bolt Set – Zinc Plated Steel
KS12THBS08P02       =    Hex Nut and Bolt Set – 18-8 Stainless Steel

Flange Adapter:
ADP12TH080101       =    Flange Adapter – 8” 150# ASME to 8” API 12 – Aluminum
ADP12TH082001       =    Flange Adapter – 8” 150# ASME to 8” API 12 – Carbon Steel
ADP12TH082002       =    Flange Adapter – 8” x 18” Oblong to 8” API 12 – Carbon Steel
ADP12TH082003       =    Flange Adapter – 8” x 22” Oblong to 8” API 12 – Carbon Steel

Y Adapter:
ADP12TH080104       =    Y Adapter – 8″ API 12 – Aluminum

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