A . prevent soot fires in the exhaust system
B . prevent exhaust gas erosion of the tubes
C . increase the velocity of exhaust gas flow
D . increase the rate of heat transfer
[单选题]F.usible plugs are installed in fire-tube boilers to _____.A.provide a means of draining the boilerB.warn the engineer of low water levelC.cool the crown sheet at high firing ratesD.open the burners electrical firing circuits
[单选题]Piston cooling fins are locatedA.atop the piston crownB.beneath the piston crownC.at the base of the piston skirtD.inside the cylinder liner cooling water jacket
[单选题]fins家族的编码产物是A.生长因子B.生长因子受体C.酪氨酸蛋白激酶D.转录因子
[单选题]英语TUB、E指()A .放大器B .铁管C .气管D .通气孔
[试题]A.ftertherobbery,theshopinstalledasophisticatesalarmsystemasaninsurance_________furtherlosses.A.)forB)fromC.)againstD)towards
[单选题]A. new Ezonexam switch is installed into an existing LAN and a new VTP trunk is set up with an existing switch. Which VLANs will be allowed on this new trunk?A.All defined VLANs are allowed on the trunk by default.B.Each VLAN, or VLAN range, that is
[单选题]Temperature control valves installed in the jacket cooling water system of a diesel engine modulates the rate of water flow through the ().A . cooling water pumpB . nozzle cooling passagesC . cylinder jacketsD . heat exchanger
[单选题]Generating tubes in waste heat boilers are finned to ().A . reduce gas flow turbulenceB . prevent exhaust gas corrosionC . increase the rate of combustionD . increase the rate of heat transfer
[单选题]Bottom blow valves are installed on auxiliary water-tube boilers to ()A . remove suspended and precipitated solids from the boiler waterB . completely drain the boiler in an emergency situationC . prevent hardened scale deposits in the water drumD .
[单选题]在MGW上,TUB板位于()A . 主机框的4&5槽位B . 扩展机框的5&6槽位C . 主机框的2&3槽位D . 扩展机框的2&3槽位