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In the United Kingdom, for historical reasons, it is the Engineering Insurance Companies which carry out the examinations of steam boilers and steam vessels required under the factory legislation. Although the legislation requires only the inspection of completed steam plant during operation the companies also carry out inspections during construction in manufacturers' works so that they get a comprehensive knowledge of difficulties which occur over a wide range of plant.

Steam contamination (solid particles in the superheated steam) comes from the boiler water largely in the carry‐over of water droplets. The need for extreme purity of steam for use in high pressure turbines has prompted the development of highly satisfactory devices for separating steam and water in a boiler drum. Consequently, steam contamination has been steadily reduced. Troublesome turbine blade deposits may occur with surprisingly low (0.6 ppm) total solids contamination in steam. In the 3.5–6 MPa range, however these deposits are usually water soluble and can be removed by periodic washing. In the 4 to 10 MPa range, however, silica deposits predominate and these deposits are not easily removed by water washing. With operating pressure of 13 MPa and above insoluble deposits do occur which may be controlled by residual water washing. Before the unit is returned to service, the deposits should be removed by air or water‐driven turbine cleaners or by chemical cleaning.

Corrosion problems in low‐pressure boiler plant systems arise chiefly in the following system components:— (i) Water Side of Boiler (Internal). (ii) Fire Side of Boiler (External). (iii) Boiler Chimney. This article discusses corrosion problems relating to low‐pressure steam boilers operating at a maximum pressure of 200 psi, space heating boilers operating on closed water circuit and domestic hot water boilers operating on a direct tap‐water circuit.

The purpose of this paper is to deal with the performance modeling and assessment of maintenance priorities for steam generation unit of a sugar plant.

The unit comprises of four subsystems, i.e., Bagasse elevator, Bagasse carrier, boiler and feed pump. The Chapman–Kolmogorov equations are generated on the basis of transition diagram and further solved recursively to obtain the performance modeling with the help of normalizing condition using the Markov approach.

Decision matrices are formed with the help of different combinations of failure and repair rates of all subsystems. The performance of steam generation unit is evaluated in terms of availability levels depicted in decision matrices and plots of failure rates and repair rates of various subsystems. The maintenance priorities of various subsystems of steam generation unit are decided on the basis of effect of failure and repair rates of subsystems on the availability of steam generation unit. The key finding is that the boiler subsystem is the most critical subsystem and hence should be kept on top maintenance priority for performance enhancement of the steam generation unit.

The acceptance of both performance modeling and maintenance priorities decision by the management of sugar plant will result in the enhancement of unit availability and reduction of maintenance cost.

THE TOTAL ENERGY PLANT located by Trans World Airline at their overhaul base at Kansas City International Airport is unique in that the prime movers for power generation are Pratt & Whitney JT4 flight engines. The plant serves the 1,200,000 sq ft airframe and engine overhaul facility, the new 500,000 sq ft superhangar for servicing 747's and L1011's, the new 500,000 sq ft administrative office building, and the new flight training centre, as well as several other smaller buildings. This is TWA's main overhaul and administrative centre for the airline.

Inhibition of corrosion is a specialised division of the science of water treatment. The necessity for treatment of industrial waters for the prevention of scale deposits and to adjust the dissolved constituents to suit a particular manufacturing process is clearly recognised, but the conditioning of the pretreated water to prevent corrosion is often not considered at all or at least given only superficial attention. It is usually not until the incidence of corrosion poses maintenance problems and affects the manufacturing process that the corrosion aspect of water treatment is looked at seriously.

Introduction Of the aspects of corrosion observed during the nineteenth century, those associated with boiler corrosion received the most systematic and exhaustive investigations. The main reason for this was that corrosion was one of the causes of boiler explosions and these caused many deaths during this period.

The Food Hygiene (General) Regulations, 1970, when they first appeared, seem to have attracted more notice in the daily press than in the specialist journals, although, while re‐enacting much that was in the 1960 regulations, which they repeal, the new measures break new and important ground, as well as introducing a number of amending provisions, which experience has shown were needed. We tend to associate hygiene needs of food and drink with the thronging streets of the city and town, the hidden backrooms of restaurants, the bustling market and the mobile food van, which, in this motorized age, has ousted the bawling backstreet hucksterer.

Until about 1953 the Central Electricity Generating Board applied only a simple alkali boil‐out before commissioning its boilers. After this time acid cleaning processes were adopted, firstly on boilers, later on feed heating plant. The course of development of the processes is described. The adoption of acid cleaning to plant after commissioning is still controversial. The reasons for applying acid are given, with the methods used. Consideration is given to avoiding the need for acid cleaning, and the methods which are available for this.

Smooth appearance of fabrics after ironing with steam, soleplate, ironing speed and their interactions cannot be studied using household ironing machines such as hang steamer and flatiron. The purpose of this paper is to present the design and verification of a simple, low-cost test platform based on the fabric materials hang-ironing factors includes temperature, humidity, ironing speed (time).

This platform achieves adjustable and stable steam flow rate, enabling any ironing speed and any temperature of soleplate below 200°C. Moreover, the whole ironing process is automatically after experiment level set ahead for better observation to the ironing process.

Regression results of the apparatus are stable, statistical significant which is verified by the statistics under design of experiment.

It is useful in other aspects such as nozzle test and improvement, new products evaluation and smooth appearance level experiment and test for new ironing product and its research. It is also useful in other aspects such as nozzle test and improvement, new products evaluation and smooth appearance level experiment and test for new ironing product and its research.