AQUALOK Pipe Products are available from: MARYLAND METRICS

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Installation Instructions Couplings and Flange Adapters PIPE END PREPARATION Pipe end preparation refers to the distance back from the end of the pipe that must be prepared to enable an effective coupling seal. It is important to note the following regarding the pipe end upon which a coupling gasket seals : =>  the pipe surface is to be round, smooth, clean, free of grooves, weld beads, bumps, score marks or other irregularities =>  in order to maintain specified coupling pressure ratings, pipe end tolerance should be within ± 0.75% of pipe outside diameter. The pipe end preparation distance for normal coupling assembly is specified by the dimension P. For the pipe end preparation distance for coupling assembly where cutting back of pipe wrapping is necessary refer to  dimension Q. Coupling NB Distance P Distance Q 50 to 150mm 100mm 165mm 200 to 300mm 125mm 195mm 350 to 600mm 150mm 225mm    AQUALOK AQ50 - AQ300 MM COUPLINGS    AQUALOK couplings and flange adapters are supplied pre-assembled ready for quick and easy installation. Fitting instructions differ slightly for products above  DN300 mm nominal bore as these are dis-assembled and then installed.    Successful installation of slip-on flexible couplings between DN50 and DN300 mm nominal bore requires adherence by the installer to the following several simple steps: 1. All pipe ends must conform to the relevant pipe end specifications as laid out by the pipe manufacturer (e.g. SABS 719 : 1971 section 4) AND as specified previously under the heading Pipe End Preparation. It is important to note that the coupling gaskets (and sometimes the coupling sleeve and end rings) be thoroughly cleaned immediately prior to assembly, as loose dirt can limit the effectiveness of the gasket seal.    The pipe end preparation distance (e.g. P = 100 mm for a DN100 mm nominal bore coupling) should be prepared to remove all dirt, rust and other foreign matter on each pipe end (Figure 1.).       2. Equi-distant reference marks should be made on each of the prepared pipe ends to facilitate accurate centering of the coupling over the specified setting gap between the pipe ends (Figure 2.). 3. A suitable gasket lubricant (such as soapy water) should be applied to each of the pipe ends and coupling gaskets before placing the coupling on a pipe end. Soapy water assists the coupling installer as the coupling will tighten easier over the setting gap. 4. The complete coupling can now be slid over the pipe end of the pipe already in position and the pipe ends aligned with reference to the correct pipe setting gap. It is important that the setting gap is correct at the time of installation and it may therefore be necessary to adjust the pipe trench bed to ensure this (Figure 3.). 5. The coupling can now be slid into position centrally over the gap between the pipe ends (Figure 4.) using the reference marks made on the pipe for means of  location. 6.The plastic nut caps can now be removed (NOT prior to this). The nut caps are supplied with each coupling to ensure the ends of bolt threads are not damaged during transportation, storage or installation, it is therefore only necessary to remove the nut caps when the coupling is on the pipe ready to be tightened. The nut caps will pop off if the nuts are finger tightened, or they may be pulled off. With the nut caps removed the coupling bolts may be tightened to the recommended AQUALOK bolt torque (as specified in Table 1.) of 70 - 80 Nm for couplings below DN300 mm nominal bore (Figure 5.). The order of tightening the bolts is very important to ensure effective sealing of the coupling gasket. COUPLING BOLTS MUST BE TIGHTENED IN PAIRS AT DIAMETRICALLY OPPOSITE POSITIONS. EACH NUT MUST BE GIVEN TWO OR THREE TURNS AT A TIME UNTIL RETURNING TO THE FIRST PAIR. This tightening sequence is important and necessary to ensure that the coupling end rings pull together evenly and the gaskets are compressed equally between pipe and coupling sleeve. The tightening sequence above must be repeated as many times as is necessary to reach the specified torque rating. It is advisable to re-torque the coupling several hours after installation to ensure the bolts are at the correct torque.     IMPORTANT NOTE: Each coupling gasket for products above DN150 mm nominal has a 'locating  lip', it is important that the installer ensure the gasket locating lip is positioned correctly (ref. figure 6.) as this product feature greatly assists the installer in locating the product evenly around the pipe. Failure to do so may inhibit the sealing capacity of the AQUALOK coupling or flange adapter. If an effective coupling seal is not maintained at the specified torque rating the coupling must be removed and re-installed following the above installation instructions.