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Ways on how initial electrical and automation design conditions the reliability and efficiency of a plant during its entire life cycle are discussed. It is believed that the selection of the best products from manufacturers is the first step in optimizing a plant. The importance of selecting the right configuration is also explained.

The readers made their choice loud and clear in the 2002 'Product of the Year' competition. After reviewing 150 finalists in the November issue, they selected Rapidgrip self-adjusting pipe wrench [...]

Successful completion of the refinery observation test run (ROTR) at the Middle East Oil Refining Co. (Midor) plant in Alexandria, Egypt, was the final step in the startup of the [...]

This paper deals with the two-machine no-wait flow-shop problem with limited machine availability. In this model, we assume that machines may not always be available, for example because of preventive maintenance. We only consider the deterministic case where the unavailable periods are known in advance. The objective function considered is the maximum completion time ([C.sub.max]). We prove that the problem is NP-Hard even if only one unavailability period occurs on one single machine, and NP-Hard in the strong sense for arbitrary numbers of unavailability periods. We also provide heuristic algorithms with error bounding analysis. Keywords. Scheduling, flow-shop, no-wait, machine availability, complexity, heuristic, performance guarantee.

This article discusses the design and installation of a 3600-ton central plant and 750,000 cfm air-side system in a Texas manufacturing facility originally cooled by a legion of split-system units [...]

Rotary screw and reciprocating air compressors have their own proper applications because of the differences in their capabilities. Rotary screw compressors are utilized mainly for applications requiring more than 30 hp and for air compression up to 150 psig. Reciprocating compressors are for applications requiring 30 hp and less, and when reliability is of prime importance. Selection criteria include the amount of air required, the optimum pressure level and the quality of air needed., Compressed air has become a vital utility in the day-to-day operations of most companies. Businesses are well aware of the need for compressors, but there is considerable debate as to [...]

The 42 CFR Part 84 is a standard set by the National Institute of Occupational Safety and Health that focuses on the filtering efficiency of air purifying respirators and filters. Plant engineers can facilitate the transition into new respirator applications through several steps. These include workplace assessment, worker needs evaluation, implementation and respirator program enhancements., In July 1995, NIOSH adopted new certification performance criteria for negative pressure, air-purifying respirators and filters. These respirators are widely used for worker protection against hazardous particles generated during operations [...]

Total Productive Maintenance is a Japanese concept of equipment management that allows a facility to improve decisively the equipment performance in the manufacturing area with the help and involvement of all employees. KEYWORDS Overall Equipment Effectiveness; Machine Availability; Performance and Quality; Unscheduled Stoppages; Schedule Stoppages; Teambuilding; Gross Operating Time; Programmed Operating Time; Net Operating Time; Work Sampling.

Synthetic lubricants are used for applications that demand better oil performance characteristics than that provided by mineral-based petroleum products. Their higher initial cost is offset by advantages which include better lubricating for the load zones and nonconforming surfaces of machines, reduced wear of machine parts and longer productive life of industrial equipment. A list of various synthetic lubricants, their performance characteristics and their applications are presented.

Proper maintenance steam systems can increase their efficiency and minimize their operating expenses. Boilers must have appropriate sizes to provide the needed amount of steam. Oversizing steam main piping reduces pressure drops and velocities and diminishes boilers' operating costs. The industrial heating equipment maintenance is discussed., Performing a few simple maintenance actions can restore equipment to its original performance parameters or better - and reduce operating costs as well Steam is an excellent heat transfer medium. [...]

The plant engineer must consider several factors when specifying oil and gas-fired packaged steam generators which are used in industrial plants to produce saturated or superheated steam. Efficiency is influenced by excess air and exit gas temperature. Pre-heat feedwater is often utilized to increase boiler efficiency by reducing exit gas temperature. Pollutants such as NOx and CO must also be regulated by flue gas recirculation, staged air/fuel combustion, selective catalytic reduction or selective noncatalytic reduction., The number of variables that need to be addressed make custom systems a popular choice Oil and gas-fired packaged steam generators [ILLUSTRATION FOR FIGURE 1 OMITTED] are used in many [...]

There are several kinds of hoisting machinery, used in industrial plants for lifting, lowering and transporting materials. These depend on the kind of application and specific load, duty and travel specifications. They are either powered by electricity or by compressed air. Hoists are usually chosen, based on the largest expected load. Safety must also be considered when choosing hoists. They should include features such as electric and mechanical load breaks, load limiting devices and limit switches., Wire rope or chain versions with electric or compressed air power serve a variety of lifting and transporting activities Powered hoists are commonly found in industrial plants raising/lowering or transporting [...]

Automatic tool dispensing machines and full-service supply systems are redefining the relationship between the toolmaker and the tool user. With these systems, toolmakers essentially become responsible for a plant's tool management function. The machines and supply systems contribute to users' control of the acquisition, possession and use of tooling and related material, while allowing companies to better manage their tool inventories as they are able to identify the department, job and machine for which a part is used., Cutting tools reach the shopfloor in novel, streamlined, and cost-effective ways. At Simpson Industries, an automotive parts manufacturing plant in Fremont, IN, Valenite tooling products come out of a vending [...]

Manual workstations, the focal point of many assembly operations, are going high-tech. Modern workstations have evolved from fixed workbenches and tables to ergonomically designed units with modular components and height-adjustable […]

Manufacturing plants use a wide variety of pumps to handle different kinds of fluids. Although pumps often have the same flow and pressure capabilities, plant engineers need to determine the specific application of the pumps before selecting which type to use. A discussion of the different types of pumps available in the market, as well as their capabilities and proper applications, is presented., The most widely used devices by plant engineers are pumps and electric motors. In terms of time, pumps came first. Since pumps have existed for such a long time and [...]

Pulse-width modulation (PWM) is the leading method of adjusting the frequency of the power supply to the motor to bring about controlled speed of an ac induction motor with sizes up to 200 hp. Problems in PWM adjustable-frequency drives usually originate from wrong specification, installation and startup calibration. One symptom of damaged components is the presence of strange smell and discoloration., Pulse-width modulation (PWM) is the predominant technology for adjusting motor supply frequency to control the speed of ac motors in sizes through 200 hp. Here are step-by-step procedures to follow [...]

Canned motor and magnetic drive pumps have solved the seal problem which causes as much as 40% of pump failures. Canned motors have an advantage over magnetic drive pumps in that the common shaft design eliminates need for alignment and external lubrication. It also has a double containment system. Other features include two bearings, no couplings or seals, low noise levels and small overall size or about 50% reduction in a conventional pumping system. In addition to this, many canned motor pumps are field repairable. This eliminates the need to return the unit to the factory for repair., Environmental concerns limit pump leakage when problem fluids are involved. Properly selected canned motor pumps fill the bill. Containing a fluid while moving it under pressure has been a problem [...]

Aggregate plants are finding that programmable logic controllers (PLC) enhance operations, information management and equipment monitoring. The PLCs provide efficient starting and stopping of plant machinery. They also reduce the wear and tear on crusher liners because material recirculation is minimized. In terms of costs, energy is saved and less labor is required to manage operations. Automation averages about $4.50 per ton based on $3 per ton for crusher-runs and $6 per ton for washed manufactured sand.

Competitive pressures in the world market have increased the plant engineer's responsibility from the automation of discrete processes to the creation of more flexibility throughout the plant floor. One result [...]

Steam Humidification Systems Humidification can be a key ingredient in the efficient operation of an industrial plant. Improper humidification can be costly and harmful to the products being made and [...]

Metal Premachining Capabilities - TCI Aluminum, Booth 3970 Premachining capabilities for aluminum, stainless, brass and copper will be exhibited. A surface improvement process which produces a consistent cosmetic finish on [...]

A tale of two rebuilds Why is Menasha's Otsego paperboard mill rebuilding its No. 1 machine just five years after a major rebuild? A commitment to continuing quality improvement. From [...]

An extensive review of dealing with obsolescence of control systems appeared on page 22 of the October 2004 issue of NEI. Following on from that article, a specific example of [...]

Key concepts * Conduit continues to be the mainstay of electrical power distribution. * Cable trays provide wiring flexibility, simplicity, and lower installation cost. * Steel conduit reduces electromagnetic fields [...]

Key Concepts * Filters cannot remove all the oil coming from a lubricated compressor. * Oil-free compressors cost more, but capital costs over a 10-yr period are only 7% of [...]

The reliability of heating, ventilation and airconditioning systems in industrial plants can be improved by evaluating motor/drive compatibility. There are instances wherein pulse width modulated ac drives are installed in ac induction motors, thereby increasing the possibility of an overshoot in the drive's rectangular output pulse. The National Electrical Manufacturers Assn offers information on the appropriate drive for a particular motor., When the plant HVAC/R system shuts down because a motor fails, more than simple replacement may be needed to get the system up and running again. In a number of [...]

Standards of productivity, cost effectiveness and worker safety must be used in evaluating and selecting steam hoses. The ideal characteristics of hoses' tube, reinforcement layer and cover should be assessed. The assessment must take into account usage guidelines such as steam pressure, temperature, frequency of use and handling. Regular maintenance and care of the steam hoses must be observed to ensure the safety of using the equipment., There are powerful economic and safety reasons for properly specifying and handling steam hose assemblies. Economically speaking, it is important to acknowledge that steam hose assemblies will fail prematurely if [...]

The T-table systems for updating work cell for streamline production installed by Trane Co have dramatically reduced die change time in the company's heating, ventilation, air conditioning plant in Fort Smith, AR. The systems have provided a flexible demand-flow schedule, leading to five-minute-die change downtime and a die changeover of 90 seconds. This has boosted the company's commitment to implement efficient but cost-effective methods in manufacturing operations., The Trane Co.'s plant in Fort Smith, Ark., is committed to demand-flow technology, implementing the most cost-effective and efficient methods in its manufacturing processes. A major producer of commercial and [...]

A demand expander enhances the efficiency of compressed air systems by controlling the maximum pressure at which air that is demanded by users is removed from the system. Expanders separate the demand and supply sides of a compressed air system, resulting in a minimum loss of energy in the expansion of compressed air from storage into the system. This results to an overall lower plant air pressure. Compressed air systems with demand expanders function ideally, eliminating the effects of leaks, unregulated use and high regulator setting., Increasing the amount of available air in a system doesn't have to mean adding compressors Artificial demand is the excess volume of compressed air created for unregulated users as a [...]

Crane modernization provides a less expensive solution to crane replacement. There are several points to remember in modernizing a facility's industrial overhead crane. These include management's reasons for the operation, the crane's structure, its maintenance history, the life expectancy of the machine, the availability of new technology, a comparison of the cost of modernization with replacement, the downtime involved and the selection of the most qualified contractor for the job., Available options and possible cost benefits often make this choice more practical than purchasing new equipment The typical life of an industrial crane spans 20 to 40 yr. Because a [...]

The use of compressed air systems by industrial plants can be maximized through a systems approach in management. This type of management calls for a study of the facility's use, distribution, storage and supply of compressed air. This study should be augmented by the establishment of performance standards and benchmarks. Finally, compressed air systems should be subjected to regular maintenance procedures and performance measurement tests., Optimum operating benefits are obtained when air systems are considered as a whole, not as individual items When production lines start humming and begin gasping for air, is it time [...]

Plants use axial fans for the ventilation of industrial processes and for ensuring worker comfort. They may be classified according to their airflow characteristics, the characteristics of their blades and the manner by which power is transmitted to them. The proper selection of axial fans for industrial applications depends on their intended use. It is important to study the system effect of installing such fans for the devices to achieve their rated performance., Three major types - propeller, tubeaxial, and vaneaxial - offer ventilation solutions for both process and comfort applications A typical plant environment may require ventilation for both industrial processes and [...]

Personal computers (PC) are increasingly being used on factory floors. This poses a number of design problems for computer manufacturers, because traditional PCs were not designed for industrial environments. Specifically, industrial PCs must be able to withstand exposure to dust, airborne particles, high ambient temperatures, humidity, splashing liquids, corrosive agents and vibration. Honeywell Inc.'s Smart Distributed Systems devices are designed to face such conditions.

Proper condensate draining of low-pressure process heaters can significantly improve their performance. Most common steam heater problems include fouling, freezing, corrosion and temperature swings. Condensate accumulation in the heater can create flooding-related problems. A closed-loop, pump/trap system allows the recovery of condensate up to 350 degrees F, and requires less expenses., Good drainage increases efficiency and extends the service life, but often more than a steam trap is needed. Steam provides an inexpensive heat source for process heaters. The higher the [...]

The air-powered, double diaphragm pump can operate safely against closed valves, while maintaining prime and discharge line pressure. These pumps can run dry for an indefinite period of time without heating up and being damaged. However, diaphragm pumps require compensation for vibration dampening, exhaust porting and servicing. These pumps can be easily detached from the system for repair and maintenance by suction and discharge line shutoff valves., These self-compensating and nonlubricated pumps require compensation for vibration dampening, exhaust porting, and servicing A nonpositive displacement pump, the air-powered, double diaphragm, differs from positive displacement pumps. Limited air pressure [...]

There are five types of steam straps which are usually used in industrial plants. The inverted bucket trap is an inexpensive device for low-to-medium pressures and medium capacity applications. The float and thermostatic trap are used for light-to-medium condensate loads and lower pressures. The thermodynamic or disk traps can be used for a wide range of pressures. Bimetallic steam traps have the advantage of being resistant to damage from water hammer. Thermostatic steam traps can be used for the widest range of pressures but not usually beyond 15,000 lbs/hr., While all traps remove condensate, operating principles dictate where each should be used Steam traps have been in existence for at least 100 yr. Back when steam systems were state [...]

The choice of steam traps for industrial plants can be facilitated by first understanding the principles and the mechanics behind the process. A steam trap is an automatic valve that discards condensate, air and carbon dioxide from steam lines. The equipment is subject to wear and ultimately becomes unusable and results in a leak in the system that wastes energy. There is not one single trap that could ideally work in all situations. Steam trap manufacturers will suggest the types that would best suit requirements., Understanding principles is the first step in the process Trying to decide what steam trap to specify is often confusing to plant engineers. A logical starting point is to understand [...]

We can't afford to upgrade our compressed air system. We don't spend that much money for compressed air. These are the types of uninformed statements sometimes heard about the cost [...]

In yesteryear, the use of stationary batteries in manufacturing plants was essentially confined to switchgear control, and the control and powering of ultracritical operations - such as steel mill ladle [...]