Machinery Spaces.com

Home || Diesel engines ||Boilers||Feed systems ||Steam turbines ||Fuel treatment ||Pumps ||Valves ||Refrigeration ||

Machinery spaces piping system - various fittings

Mud boxes: Mud boxes are fitted into the machinery space bilge suction piping. The mud box is a coarse strainer with a straight tailpipe down to the bilge . To enable the internal perforated plate to be cleaned when necessary, the lid of the mud box is easily removed without disconnecting any pipework.



Suction pipes

Suction pipes in tanks should be arranged with a bell mouth or foot. The bell end or foot should provide an inlet area of about one-and-a-half times the pipe area.

It should also be a sufficient distance from the bottom plating and nearby structure to provide a free suction area, again about one-and-a-half times the pipe area.

Mud box

Fig:Mud box


Steam traps

Steam trapFig:Steam trap

A steam trap does as its name implies and permits only the passage of condensed steam. It operates automatically and is situated in steam drain lines. Various designs are available utilising mechanical floats which, when floating in condensate, will enable the condensate to discharge . Other designs employ various types of thermostat to operate the valve which discharges the condensate.

Expansion pieces

Expansion bellows pieceFig:An Expansion bellows piece

An expansion piece is fitted in a pipeline which is subject to considerable temperature variations. One type consists of a bellows arrangement which will permit movement in several directions and absorb vibration . The fitting must be selected according to the variation in system temperatures and installed to permit the expansion and contraction required in the system.


Drains

Drains are provided in pipelines and usually have small cocks to open or close them. It is essential that certain pipelines are drained regularly, particularly in steam systems. When steam is admitted to a pipeline containing a reasonable surface of water it will condense and a partial vacuum occur: the water will then be drawn along the pipe until it meets a bend or a closed valve. The impact of the moving water in the pipework will create large forces known as 'water hammer', which can result in damage to pipework and fittings.

Piping systems for cargo ship's machinery spaces

A ship's machinery space contains hundreds of metres of piping and fittings. The various systems are arranged to carry many different liquids at various temperatures and pressures. The influences of operational and safety requirements, as well as legislation, result in somewhat complicated arrangements of what are a few basic fittings. Valves, strainers, branch pipes, etc., are examples of fittings which are found in a pipe system.



Pipes

Machinery space pipework is made up of assorted straight lengths and bends joined by flanges with an appropriate gasket or joint between, or very small-bore piping may use compression couplings. The piping material will be chosen to suit the liquid carried and the system conditions. Some examples are shown below .

Where piping is to be galvanised, the completed pipe with all joints fully welded is to be hot dipped galvanised. The pipes are supported and held in by hangers or pipe clips in such a way as to minimise vibration. Steam pipes or pipes in systems with considerable temperature variation may be supported on spring hangers which permit a degree of movement. An alternative to spring hangers is the use of expansion loops of piping or an expansion joint.


Machinery space pipework material

Waste steam :Carbon steel to BS 3601

SW circulating :Aluminium brass

Wash deck and firemain :Carbon steel to BS3601 — galvanised

Bilge and ballast :Carbon steel to BS3601 - galvanised

Control air :Copper

Starting air :Carbon steel to BS 3602


All system pipework throughout the vessel is to be periodically inspected for condition and security in a systematic manner and be reported upon in the PMS. It is of utmost importance to include in these inspections the pipework located in those spaces that are remote, poorly lit and may be difficult to access.

Particular attention should be paid to sea water pipework which may be subject to corrosion and wastage on both internal and external surfaces, and opportunity should be taken whenever possible, and certainly during drydocking periods, to establish pipewall condition by hammer testing and visual inspection of internal surfaces in locations where valves or pipe sections have been removed for routine maintenance, repair or replacement. Defective pipework is to be replaced at the earliest convenient opportunity.




Related Info:

  1. Various valves arrangement for machinery spaces piping system
  2. Straight-through cocks, Globe valve,Non-return valves,gate valves,Relief valves, quick closing valves, valve chests....

  3. Mud boxes, Suction pipes, Steam traps, Expansion pieces & Drains for Machinery space piping system
  4. The mud box is a coarse strainer with a straight tailpipe down to the bilge..Suction pipes in tanks should be arranged with a bell mouth or foot..An expansion piece is fitted in a pipeline which is subject to considerable temperature variations..Drains are provided in pipelines and usually have small cocks to open or close them.....

  5. Reciprocating displacement pumping system for ships use
  6. The displacement pumping action is achieved by the reduction or increase in volume of a space causing the liquid (or gas) to be physically moved. The method employed is either a piston in a cylinder using a reciprocating motion, or a rotating unit using vanes, gears or screws.

  7. Centrifugal pump principles and working procedure
  8. In a centrifugal pump liquid enters the centre or eye of the impeller and flows radially out between the vanes, its velocity being increased by the impeller rotation....

  9. How a pneumatically control valve works ?
  10. Many pneumatic devices use a nozzle and flapper system to give a variation in the compressed air signal.A typical pneumatic control valve is shown in Figure . It can be considered as made up of two parts—the actuator and the valve. A flexible diaphragm forms a pressure tight chamber in the upper half of the actuator and the controller signal is fed in.....

  11. Domestic water systems for general cargo ship
  12. Domestic water systems usually comprise a fresh water system for washing and drinking and a salt water system for sanitary purposes . Both use a basically similar arrangement of an automatic pump supplying the liquid to a tank which is pressurised by compressed air...

  13. Bilge and ballast systems for general cargo ships
  14. The bilge main is arranged to drain any watertight compartment other than ballast, oil or water tanks and to discharge the contents overboard. The number of pumps and their capacity depend upon the size, type and service of the vessel.....




Marine machineries - Useful tags

Marine diesel engines ||Steam generating plant ||Air conditioning system ||Compressed air ||Marine batteries ||Cargo refrigeration ||Centrifugal pump ||Various coolers ||Emergency power supply ||Exhaust gas heat exchangers ||Feed system ||Feed extraction pump || Flow measurement || Four stroke engines || Fuel injector || Fuel oil system || Fuel oil treatment ||Gearboxes || Governor || Marine incinerator || Lub oil filters || MAN B&W engine || Marine condensers || Oily water separator || Overspeed protection devices || Piston & piston rings || Crankshaft deflection || Marine pumps || Various refrigerants || Sewage treatment plant || Propellers || Power Plants || Starting air system || Steam turbines || Steering gear || Sulzer engine || Turbine gearing || Turbochargers || Two stroke engines || UMS operations || Drydocking & major repairs || Critical machinery || Deck machineries & cargo gears || Control and instrumentation ||Fire protection ||Engine room safety ||






Machinery Spaces.com is about working principles, construction and operation of all the machinery items in a ship intended primarily for engineers working on board and those who working ashore . For any remarks please Contact us

Copyright © 2010-2016 Machinery Spaces.com All rights reserved.
Terms and conditions of use
Read our privacy policy|| Home page||