Product Name: Best Seller Carbon Steel Road Transportation Tank Manhole Cover, Manlid Model NO.: C801TAF-460 Material: Carbon Steel P/V Vent: with Connection: Bolt & Nuts Process: Paint Gasket: NBR Key: with 2 PCS Secondary Lock: Yes Trademark: DonOO Transport Package: Carton Specification: 16" Origin: Zhejiang Wenzhou China Product Description Internationallyacceptedandspecifiedbyoilcompaniesaroundtheworldtoassistwiththesafeconveyanceofpetroleumbasedproducts.The Donoo rangeof manholecoversofferunrivalledsafetyfeaturesandoperationalbenefits.Pressureandvacuumventfittedasstandardfortankbreathing;variousratingsareavailabletosuitoperationalrequirements.SpringloadedfillcapprovidesemergencyfireengulfmentventingtoNTTCDOT406,requiredintheeventofthetankbeingexposedtoafire.Emergencyventingcapacity7000m3/h,airat350mb.AutomaticsealingofthePressureandVacuumventinarolloversituationpreventsdangerousandcostlyspillage.Self-aligningsealensurespressuretightoperationatalltimes.Twostageopeningallowssafereleaseofresidualcompartmentpressurebeforefullyopeningfillcap.Secure12and24boltfixingvariantsavailable.250mm(10")fillcapforsafe,troublefreetoploading.Highqualitydiecastbaseplateandcomponentmaterialstointernationalstandardsareusedfordurabilityandperformance.Lowprofiledesignminimisesrolloverprotectionrequirements.Securityfacilityforpadlock,wireorplasticseal.Accessoryportsfor threadedcompartmentventvalveandover-spillpreventionprobe.ThebaseplatecanbesuppliedwithaccessoryholesfortankersthataretobeconvertedtoBLVRlater.