Economical Thief Hatch

  • The Model 200 Tank Vent Thief Hatch (TVTH) is a budget-conscious choice for integrated thief access and pressure + vacuum relief, offering economical pressure- and vacuum relief for sweet service applications.
  • For sour applications, consider the Model 300 TVTH, which has the soft eFKM (sponge viton) gasket for improved sealing performance in sour applications.

Flush Top-Mount design

  • The pressure and vacuum relief mechanism operates above the tank roof to maintain functionality if the thief hatch opening is irregular or undersize.

Variety of Pressure Settings

  • Both the Model 200 and Model 300 are available with a wide variety of factory-set pressure relief settings.
  • Vacuum relief is fixed at 0.4 ozsi for both.


Function Venting Gauge Hatch; Tank Access + Pressure & Vacuum Relief
Temperature Range (TVTH 200) -40°C to 75°C (polyisoprene)
Temperature Range (TVTH 300) -26°C to 200°C (eFKM/Viton)
Pressure Relief Type Spring-loaded pallet
Pressure Relief Range 4 to 32 ozsi (see Relief Settings)
Vacuum Relief Range 0.4 ozsi fixed
Tank Connection 8” API (Fig 1 API 12F)

Related Documents


Download Brochure

TVTH Operation & Maintenance

Download TVTH Operation & Maintenance Guide

Vent Sizing Charts

Download Venting Sizing Charts

Ordering Information

TVTH 200 and 300s are stocked in Edmonton, ready to ship 1-day or less.

For Sweet Service

  1. Specify TVTH 200 Thief Hatch
  2. Specify Pressure Relief Setting (4, 6, 8, 12, 16 or 32 ozsi)

For Sour Service

  1. Specify TVTH 300 Thief Hatch
  2. Specify Pressure Relief Setting (4, 6, 8, 12, 16 or 32 ozsi)
  3. Specify spring material (302 SS standard, Inconel available)

See part number matrix on the brochure for more information.

Consider completing your Model 200 or 300 TVTH Installation with a RiserBolt Kit and Tank Gasket.

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