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BOLTING OVERVIEW
In nearly every heavy industrial application, turning threaded fasteners - nuts and bolts - is generally viewed by two criteria:
1.The need to fasten tightly enough to prevent movement of parts and achieve a good seal without exceeding the fastener's elasticity level, and
2.Successful removal of fasteners after long periods of environmental exposure to harsh conditions.
When installing heavy-duty fasteners, there are times when a little more power is required, or in other instances, a lot more power. After all, when it comes to turning nuts and bolts, especially stubborn corroded ones, what could be more basic than power?
The seemingly apparent answer to that question can be profoundly consequential: You need controlled power. That is, controlled "torque." Otherwise, you could outdo yourself and strip threads, break boltheads or even cause personal injury.
Current practice working with heavy-duty threaded fasteners in Nigeria have aimed at sheer torque power, using long lever arms and heavy hammers on slugging wrenches. Most of the foreign oil majors and servicing companies in Nigeria apply torque power with a complete range of torque control products, including manual and powered hydraulic/pneumatic torque wrenches in other countries which they operate, but their operating mode in Nigeria is quite different. These companies utilize long lever arms and heavy hammers on slugging wrenches that have proven to be very slow, inaccurate, inefficient and mostly unsafe in their operations in Nigeria.
The underlying problem with this mode of operation is facility reliability and uptime. The solution is to find ways to eliminate unscheduled equipment downtime. The problem with downtime is that most maintenance people think, "It just happens. Then we fix it." The problem with downtime is, "You can monitor it, measure it, log it, report it, track it, attack it, or delegate it, but downtime will not go away until you "eliminate it" - prevent it from happening in the first place.
Facility installation and maintenance are critical components for a company to deliver capacity and quality. To compete in today's global economy and to increase profits, many companies are moving to "Critical Bolt Torquing" the next step beyond "Just In Time." When critical machines go down for a "maintenance break, the critical questions to ask are:
>How were the fasteners torqued?
>In what order were fasteners tightened?
>What is the best way to verify the torque on fasteners?
>How does torque value vary over time?
THE RIGHT KIND OF EQUIPMENT
The tension joint, however, relies on the tension of the bolt to hold two joined parts together. The greater the tension on the bolt, the more force holding them together. Steel and most metals have a property known as fatigue, which means that they lose strength upon repeated loads. Most joints are subject to variations in load that either adds or decreases the tension in the bolt. A bolt in a tension joint will fail from fatigue if it is not tightened enough, and it will fail from fatigue and overload, if it is tightened beyond its ultimate strength. It is extremely important that we achieve the proper tension on the bolt-not too much and not too little.
The need to get the correct tension is why torque wrenches are used. What do torque wrenches have to do with tightening fasteners? We know that if a bolted joint is not tightened enough it may come apart, or it can break from being too tight. It can even break from being too loose. Torque wrenches help overcome some lack of knowledge and experience but only if they are properly used.
The utilization of hydraulic/pneumatic bolting equipment allows for a safer and faster means of the breakout of large or frozen bolts as well as highly accurate means of tightening those same bolts. From less that one inch-ounce to more than 100 thousand foot-pounds, these torque control tools provide torque, making it easier and often safer to assemble and service-threaded fasteners while reducing application problems and tool costs. When the importance of ensuring the integrity of the bolts, seals, flanges, and process equipment is being considered, Hydraulic/pneumatic bolting equipment can help realize a huge potential savings in manpower and equipment cost. The advantages will be especially beneficial in heavy-duty torque fastening applications for facility installation and maintenance in Nigeria.
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