Impurities from the boiler water surface can be removed through the （）.

相似题目

• The exhaust boilers are used to recover some of （） carried in the exhaust gas from the main engine.

  A . water B . oil C . heat D . steam

  查看最佳答案

• Clean oil is achieved in a clarifier bowl where the impurities and water collect at the bowl （）.

  A . bottom B . top C . center D . periphery

  查看最佳答案

• If the feed pump for an auxiliary boiler fails to deliver the feed water to the boiler, the cause maybe （）.

  A . high steam pressure in the boiler B . abnormally high feed water temperature C . abnormally high boiler water temperature D . steam demand exceeding feed pump capacity

  查看最佳答案

• Safety valves on a boiler vent to the （）.

  A . fuel tank B . bilge C . atmosphere D . auxiliary exhaust line

  查看最佳答案

• A shallow dish positioned at the normal water level is connected to the（）This enables the blowing down or removal of scum and impurities from the water surface.

  A . main stern stop valve B . auxiliary steam stop valve C . scum valve D . blow down valve

  查看最佳答案

• （） are mounted in pairs to protect the boiler against overpressure.

  A . Safety valves B . Water tubes C . Steam stop valves D . Blow down valve

  查看最佳答案

• The（）enables water to be blow down or emptied from the boilerIt may be used when partially or completely emptying the boiler.

  A . main stem stop valve B . auxiliary steam stop valve C . feed check or control valve D . blow down valve

  查看最佳答案

• When a clarifier is running the impurities and water collect at the bowl （）.

  A . center B . periphery C . inlet D . upper part

  查看最佳答案

• The water level in a steaming auxiliary boiler will always （）

  A . rise when the steam pressure is increased B . remain constant as long as the feed pump operates C . fall when the steam pressure is decreased D . vary as the steam demand change

  查看最佳答案

• The feed water to the boiler will comprise （）.

  A . condensate B . a small amount of make-up feed C . A and B D . None of the above

  查看最佳答案

• When a boiler is operating, the water level in the gauge glass reads （） when the boiler is shut down.

  A . lower than B . higher than C . as much as D . the same a

  查看最佳答案

• The valve that prevents water from backing out of the boiler into the feed line is the（）.

  A . bottom-blow valve B . skin valve C . feed-check valve D . feed-stop valve

  查看最佳答案

• A dazzling white burner flame in the boiler furnace indicates （）.

  A . no combustion B . deposits in the fuel C . excessive air in the fuel D . cold fuel oil

  查看最佳答案

• The fuel supply system to an automatic auxiliary boiler, will be automatically shutdown if the boiler （）

  A . salinity is abnormally high B . steam demand is too high C . water level is abnormally low D . feedwater flow is low

  查看最佳答案

• The donkey boiler may be given a bottom blow （）

  A . to raise water level B . only while making steam C . to remove scum D . when fire are secured

  查看最佳答案

• Flame failure in an automatically fired auxiliary boiler can from a/an （）

  A . incorrect electrode setting B . incorrect nozzle position C . clogged fuel nozzle D . broken high tension lead

  查看最佳答案

• Which one is not the normal operation for boiler shutdown?（）

  A . Carry out soot blowing if permissible B . Change fuel supply to diesel oil C . Close steam stop valves on boiler when pressure is reduced D . Drain boiler empty when it has cooled dow

  查看最佳答案

• The boiler is fired （） the demand for steam exceeds that available from exhaust gas heating.

  A . whenever B . however C . wherever D . whether

  查看最佳答案

• The purpose of the safety relief valves installed on an auxiliary boiler is to （）.

  A . relieve excess fuel oil pressure during the “off” fire cycle B . admit water to the dry pipe C . throttle the forced draft fan output for proper combustion D . reduce excess steam pressure in the boiler

  查看最佳答案

• The procedures recommended for auxiliary boilers having high salinity include （）.

  A . treating with oxygen scavengers B . securing the boiler and giving it a blowing down C . increasing the pH D . reducing the phosphate level

  查看最佳答案

• The percentage of impurities in a specific fuel oil sample is determined by （）.

  A . settling in a fuel tank B . testing in a laboratory centrifuge C . burning in a calorimeter D . testing in a closed cu

  查看最佳答案

• The boiler water alkalinity in a coil-type auxiliary boiler should be maintained at the pH recommended by the boiler manufacturer to（）

  A . precipitate silica from solution B . reduce corrosion in the heating coil C . prevent clogging and erosion in the coil D . maintain zero water hardne

  查看最佳答案

• Les Shield, _______, a boiler technician, was made redundant from British Steel at Consett in______________.

  查看最佳答案

• The valve that prevents water from backing out of the boiler into the feed line is the______.

  A.bottom-blow valve B.skin valve C.feed-check valve D.feed-stop valve

  查看最佳答案