Open systems using gravity tanks, etc., are rarely met nowadays and Figure 1.8 shows a characteristic arrangement of pressure tanks, calorifiers and pumps for a large ship. The fresh water pumps are self-priming, drawing from storage tanks and discharging through filters to a rising main, branched to give a cold supply and a hot supply in closed circuit through a calorifier. A tank kept under pressure by an external supply of compressed air rests on the system and provides the head necessary

Oil fuel transfer arrangements provide for receiving stations at an upper deck level, port and starboard, furnished with valves, elbows, pressure gauges, filters and relief valves

A fire and bilge pump has suctions from sea, bilge main and engine room bilge, with discharges to fire main, oily water separator and overboard. A ballast pump has suctions from sea, ballast main, engine room , bilge direct and bilge main with discharges to overboard, the ballast main, the oily water separator and possibly, the main salt water circulating system

Air at high pressure, i.e. at 25 bar or more, is required for starting main and auxiliary engines in motorships. Air at low pressure, say at 6 bar or less is required for much remote or temperature or pressure controlled equipment, for which purpose it must be clean and oil-free

There are branch pipes to the separators and occasionally to the settling tanks (blanked). Other branch pipes lead to the deck filling lines (also blanked) so that the oil can be discharged ashore

In motorships the oil, after passing through main and motion bearings and oil-cooled pistons, etc., is either retained in the bedplate or flows by gravity to a sump tank. In either case, the oil pumps, which may be self￾priming, submerged centrifugal or rotary positive displacement, draw the oil through magnetic strainers and discharge to: filters - oil coolers - engine lubricating and/or cooling manifolds

In motorships there are two main circuits, one salt , one fresh. The salt circuit is: sea inlet box (seachest) - pump(s) - f.w. coolers in series (first LT then HT) – turbo blower aftercoolers in parallel (if any) – provision condenser in parallel (if any) - overboard

Provide for data logging, remote control and automatic action-pneumatic electro￾pneumatic, and electronic equipment, self￾regulating apparatus, etc. The chapter will give a general instruction above system and function. The other chapters of the book focus on the oil handling devices onboard

这本《航海学习题集》是面向航海类船舶驾驶专业学员，配合郭禹教授主编的高等学校 统编教材《航海学》特别编写的。其目的是给学员选择恰当的课后习题，同时，帮助学员更 好地理解教材内容，举一反三，融汇贯通。 习题集按教材章节顺序编写，基本上涉及到了主要知识点。考虑近年来港监考试和学生 结业考试题型的特点，适当地增加了选择题的份量，包括思考题、问答题、计算题和选择题 多种题型

（一） 车辆轮轴型式和荷载 公路路面设计中，通常用轮组系数和轴数系数来考虑车辆的轮数和轴数。 机场道面设计中，通常以使用该机场的主要飞机的最大起飞质量作为计算依据