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Superbolt ® Multi-Jackbolt Tensioners (MJTs) USER MANUAL V01_2024_03 Lubrication and tools Tightening procedure Loosening procedure Maintenance General notes Nord-Lock International AB T: +46 40 602 46 00 E: info@nord-lock.com www.nord-lock.com...
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CONGRATULATIONS! With Superbolt Tensioners you have chosen a technologically superior product. It is purely mechanical and, therefore, very safe. The following simple steps will help you with your application. Thereby you increase safety, speed and service life. THE SUPERBOLT PRINCIPLE How it works By tightening the jackbolts, a strong thrust (axial) force is generated.
1. LUBRICATION AND TOOLS NOTE Nord-Lock Group can supply the tools and lubricants referenced in this section. Please contact Nord-Lock Group for more information. 1.1 Lubricants Lubricants play a vital role in the proper performance of Superbolt products. Only use the correct Superbolt-specificed lubricant. Refer to the Superbolt data sheet or certificate for the correct lubricant.
1.3 Manual tools Good quality calibrated torque wrenches are the basic tools needed for most Superbolt jobs. Click-type versions are widely available in various sizes depending on the target torque. RECOMMENDED TORQUE WRENCH SIZE GUIDELINE: – 1/4” Drive 5 Nm (40 lbf-in) to 22 Nm (200 lbf-in) –...
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NOTE Unlike tightening, power tools are not suitable for loosening jackbolts during Steps 1 through 3 because jackbolts must be unloaded gradually. A power tool can be used only at Step 4 to completely extract jackbolts. NOTES FOR THE USE OF AIR IMPACT TOOLS Network pressure min.
2. TIGHTENING PROCEDURE 2.1 Torque check Recommended torque values can be found on: NOTE - Your internal directives. The jackbolt torque marked on the MJT body is the maximum value, which may - Superbolt certificate. be unsuitable for your application. The - Superbolt data sheet.
2.4 Tightening 100% STEP 1 STEP 2 Tighten these 4 jackbolts Tighten the same 4 jackbolts crosswise crosswise with 50% of the with 100% of the recommended torque. recommended jackbolt torque. NOTE Should several tensioners be loosened, i.e. on a flange, perform Step 1 on all tensioners before moving to Step 2.
3. LOOSENING PROCEDURE ATTENTION Loosening requires an exact procedure. The jackbolts must be unloaded stepwise! Under no circumstances should single jackbolts be unloaded completely. The remaining jackbolts would have to carry the entire load and, therefore, would be difficult to loosen. In extreme cases the jackbolts could mushroom and make loosening impossible! 3.1 Usage at normal temperatures (<100°C or 212°F) PREPARATION...
3.2 Usage at high temperatures (>100°C or 212°F) PREPARATION At higher temperatures, the petroleum base of the lubricant evaporates, thereby increasing the effort for loosening. Therefore strict adherence to these steps is essential for success. As always, be sure to follow the lubricant manufacturer’s safety instructions.
- Again, the next two jackbolts should become free, and so on. Other problems - Afterwards, relieve all jackbolts according to the - Please contact Nord-Lock Group or your standard loosening procedure. supplier directly. SUPERBOLT — MULTI-JACKBOLT TENSIONERS USER MANUAL...
5. GENERAL NOTES 5.1 Tightening tensioners with only 4 or 6 jackbolts 100% STEP 1 STEP 2 Tighten 2 opposite jackbolts with Tighten 2 other opposite jackbolts with 50% of recommended torque. 100% of recommended torque. 100% 100% <20° STEP 3 STEP 4 Change to circular tightening and Repeat Step 3 until all jackbolts...
5.3 Tightening of long tie rods To accelerate tightening of long tie rods, it pays off to perform step 4 with increased jackbolt torque (approx. 110–125%). Attention: In final rounds, always check jackbolt torque by hand with 100% to prevent overloading. 5.4 Tensioning large flanges or joints For tensioning large flanges/joints, preferably...
The same can be true for bolts of earlier manufacture that were manufactured with other tolerances. The Nord-Lock Group can also supply mating studs and bolts for our tensioners. Please contact your local Nord-Lock Group representative/office for more information.
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Nord-Lock Group or your supplier directly. Exclusion of liability Nord-Lock Group excludes all liability for unsuitable product selection, improper use as well as damage resulting from disregarding our instructions and directives. Changes due to technical progress are reserved.
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