Installation of slip-end foot bolt nuts for horizontal tank saddles

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This post was last edited by Zhongyuanren on 2024-9-4 at 19:05. Installation of the foot bolt nuts for the sliding end saddle of horizontal tanks: The sliding end saddles of horizontal tanks are usually equipped with oblong holes, in order to accommodate the displacement that occurs due to thermal expansion when the temperature rises and thermal contraction when the temperature drops. Of course, corresponding measures also need to be taken during the installation and positioning of the equipment in order to effectively ensure the displacement (sliding) of the saddle due to thermal expansion when the temperature rises and thermal contraction when the temperature drops. The direct question is the specific requirements regarding the tension on the anchor bolt nuts at the sliding end. The obvious answer is not to tighten it too much, as otherwise the friction between the saddle base plate and the embedded steel plate in the foundation (or the sliding plate) will be too high, preventing sliding and thus preventing the intended function of this design from being achieved. There are no relevant requirements in the actual standards for horizontal equipment; therefore, I have examined what the relevant equipment installation standards stipulate. Clause 4.4.4 of the GB50461-2008 Standard for Quality Inspection of Construction of Installation Works for Static Petrochemical Equipment stipulates that the anchor bolts at the sliding ends of horizontal equipment should be located in the middle of the oblong holes in the supports, with the position deviation being such as to compensate for the expansion and contraction caused by temperature changes ； Clean the sliding surface of the bearing and apply lubricant ； After the piping for the equipment is completed, loosen the nut of the foundation bolt at the sliding end support to create a gap of 1–3 mm between it and the support plate, then tighten the locknut. File:///C:\Users\admin\AppData\Local\Temp\ksohtml28164\wps1.jpg Clause 5.3.3 of the SH/T3542-2007 Standard Specifications for Construction Techniques of Petrochemical Static Equipment Installation stipulates that the contact surface of sliding end supports should be coated with grease. The distance between the anchor bolts and the ends of the corresponding oblong holes should meet the expansion requirements. After the process piping is completed, loosen the nut of the sliding end support to leave a gap of 1–3 mm between it and the support surface, and then install a locking nut. According to clause 4.4.7 of the HG/T20236-2021 Standard for Quality Inspection of Construction of Chemical Equipment Installation Projects, the anchor bolts at the sliding ends of horizontal equipment should be located in the middle of the oblong holes in the supports, with their position tilted in the direction of expansion (contraction) caused by temperature changes ； Clean the sliding surface of the bearing and apply lubricant ； After the piping for the equipment is completed, loosen the nut of the foot bolt at the sliding end support to create a gap of 1 mm to 3 mm between it and the support plate, and then tighten the lock nut. According to clause 3.5.5 of the HG/T20275-2017 Standard Specifications for Construction and Acceptance of Chemical Equipment Projects, for horizontal equipment that experiences expansion or contraction at operating temperatures, the anchor bolts on the sliding side should be tightened first. After the equipment is installed and the pipelines are connected, a gap of 0.5~1.0 mm should be left by loosening the nuts, after which the locking nuts should be tightened again, with this gap being maintained. However, when a sliding base plate is used, the sliding surface of the equipment support should be cleaned and lubricated. file:///C:\Users\admin\AppData\Local\Temp\ksohtml28164\wps4.jpg In summary, the steps for tightening the nut at the sliding end are as follows: 1) Clean the surface of the bearing at the sliding end and apply lubricant to it ； 2) Tighten the nuts of the sliding end foot bolts, and carry out piping work ； 3) After completion, loosen the nut to leave a gap of about 1.0 mm (the gap should not be too large) ； file:///C:\Users\admin\AppData\Local\Temp\ksohtml28164\wps5.png4) Install a lock nut (as a anti-loosening measure). Heat exchanger equipment technology community