Economics of Hot TappingThis article illustrates the importance of comparing hottapping and shutdown methods to determine which ismore cost-effective and fit for purpose for differentapplications. A cost-benefit analysis is a powerful toolthat can be used to conduct a comparison of these twomethods.
TABLE OF ine Maintenance, Upgrade and repair optionsConsiderations in choosing between shutdown and hot tappingThe EconomicsProject CostingHot Tapping CostsCost Benefit Analysis2233345126.96.36.199.1.22.2Line Repair Case StudyBackgroundHot Tapping CostComplete Shutdown CostCost Benefit Analysis667783Conclusion94References101 ION Pro Services 2020
1. INTRODUCTION1.1PIPELINE MAINTENANCE, UPGRADE AND REPAIR OPTIONSMaintenance, emergency repairs, and upgrades form a significant part of any pipeline and plantoperations. These include, inter alia : Attaching a branch connection to the lineInstalling an internal probe or monitorTo stop or redirect ﬂow in a line for maintenance or repair purposesPositioning a branch ﬁtting on an operating pressurized line, ﬂowing or stagnantRemoving defects, i.e., dents or pipeline damageThere are two main methods to conduct these routine and emergency procedures on pipelines; theyare hot tapping and shutdowns. And each has its costs, benefits, and risks involved, requiring thoughtand investigation on the part of the owner to choose the most appropriate.These two methods are brieﬂy described as:ShutdownA shutdown halts production in the pipelines temporarily to enable the safe execution of the work on apipeline without it being live. While a shutdown allows the safe access needed to perform the neededmaintenance and repairs, it has obvious cost implications with the loss of production throughput.Some of these associated costs with a shutdown are:1.Loss of revenue (while the system is shutdown)2.Maintaining compliance with national, state, and local regulations when shutting the systemdown is costly.3.Potential costs of litigation and associated political ramifications are also a common concernand reality with system shutdowns.Hot Tapping & Line StoppingHot tapping, also known as line tapping, pressure tapping, pressure cutting, or side cutting , and linestopping method enables expansion and modification of pipe networks to be done under pressurewithout any interruption or stopping the network. Hot tapping is a common practice when specific partsof a pipeline network have been damaged or require modifications. Line stopping isolates certain partsof the pipeline network, which can support hot tapping services.Hot tapping is a specialized procedure. Several factors need to be evaluated to determine if it is afeasible option before it can be considered a potential solution, including the condition of the pipeline,operation pressure, and pipe material. It is also essential to consider nearby emergency valves that canisolate the line, the working space around the connection, the location of other weld imperfections, andthe tap diameter.2 ION Pro Services 2020
1.2CONSIDERATIONS IN CHOOSING BETWEEN SHUTDOWN AND HOT TAPPINGThere are various factors for stakeholders to consider when choosing to use hot tapping/line stopping orto perform a full shutdown. They include, among other things: Economic Environmental Access to skilled staff (how readily available are hot tapping skills to the client) Duration available for repairs Local by-laws Service Level Agreements Etc.This article only deals with the economic portion of such a decision.Because it is specialized, hot tapping can be expensive. It does, however, hold signiﬁcant beneﬁts, suchas uninterrupted production and reduced emissions. It further reduces product losses, which can saveadditional costs for the company. The argument is often made that a standard shutdown procedure is less expensive and, therefore, morecost-effective than hot tapping. However, it is essential to look at the procedures holistically, not only thecosts but also the benefits and losses involved with each.A high-level comparison of the two methods is not sufficient. A more in-depth look at the economicsinvolved with each is required to enable a fair comparison.It is important to note that the economic drivers of such a choice are only a part of the decision-makingprocess, as all other factors need to be considered.1.3THE ECONOMICS1.3.1 PROJECT COSTINGTo evaluate different cost estimations for a specific project, the best method to use is a cost-benefitanalysis . A cost-benefit analysis is a simple comparison of the estimated costs associated with aproject or approach against the possible benefits of the project or approach.When doing a cost estimation for a project, the costs can be divided into two main categories, direct andindirect costs. Direct costs are broadly classiﬁed as being directly associated with the cost of executingthe project. In contrast, indirect costs cannot be allocated to a specific project but are shared acrossmultiple projects, e.g., project management, quality control, etc. For the purpose of this article and staying with a simple project economics example, there is noconsideration for indirect costs.3 ION Pro Services 2020
The direct costs can be broken down into the following subcategories ilitiesContingency CostsMore detail on techniques and methods of estimating costs on a project can be found here. Evaluationof hot tapping and shutdown procedures, use the above subcategories to calculate the cost of each.1.3.2 HOT TAPPING COST BREAKDOWNIn order to do a cost-benefit analysis, the direct cost estimation for hot tapping needs to be completed.This is done at the start of a project and may often be a high-level cost estimation – depending on howmuch information is available at this stage. It is valuable to utilize previously completed project costings(if available) or to consult a hot tapping specialist to ensure realistic values are used and ensure asufficient level of confidence is obtained in the evaluation.Table 1 provides the cost breakdown for a typical hot tapping procedure.TABLE 1: HOT TAPPING COST BREAKDOWNItemDescriptionCost SubcategoriesIncludedMaterialsRaw materials and consumables tocomplete the actual upgrade/repair work,such as a valve.MaterialMechanical works (hottapping, line stopping,welding, etc.)Hot tapping equipment and service toperform the work. All welding, includingthe bypass line to gain access to an areathat will be worked on.Material, LaborEquipment, ServiceSite Establishment andTransportation CostsInfrastructure and offices, excavations, etc.required to be able to work in the area.Facilities, Labor, ServicePipeline EvaluationsInspection and testing done on thepipeline before the repair can be done.Service, LaborEquipmentManagementProject managementrequired.meetingsService, LaborPre-Commissioning andTestingCold/Pre-commissioning and testing thatneedtobedonebeforehotcommissioning can be performed.Service, LaborCommissioningHot commissioning after work has beencompleted for final acceptance.Service, LaborPreliminary and GeneralAny ad-hoc costs involved in the project,upgrading schedules, fencing, additionalsecurity required at the site, etc.Service, Facilities,Contingencyand4 ION Pro Services 2020The Mechanical works itemincludes the labor, material,and services involved in hottapping. In some cases, itmay be listed separately. Forsimplification in this article,it has been groupedtogether.
1.3.3 COST BENEFIT ANALYSISIt is important to note that some costs are applicable to both hot tapping and shutdown philosophies.And so, the cost-benefit analysis can be simplified by excluding these costs. They typically are: MaterialsSite Establishment and Transportation CostsManagementPreliminary and GeneralThe Pre-Commissioning and Testing task could have higher costs associated with hot tappingoperations than for shutdown due to additional testing required for the hot tapping equipment, if notperformed at the service provider's cost. Similarly, additional costs can be incurred for pipelineevaluations, as hot tapping is highly dependent on the integrity of the pipeline. This is not only for thehot tapping location but also for the up and downstream sections of the pipe.For commissioning, the hot tap operation could have a lower associated cost as a smaller section of thepipeline needs to be recommissioned. During a shutdown procedure, a large section of the pipelinemay need to be recommissioned after the repairs/work have been done, which could incur additionaltime leading to increased production losses.An additional cost that needs to be accounted for when conducting the cost-benefit analysis is a carbontax, which has only recently been implemented in countries across the world. In some locations thiscould have no impact, and in others it could be substantial cost item. This is mostly relevant for a gaspipeline where a shutdown procedure results in large emission quantities due to gas venting. In somecountries, this would result in additional tax penalties associated with the increase in emissions. The gasemissions during a hot tap are much lower than for a shutdown.A significant factor that also needs to be accounted for is the impact of the procedure on productionloss. This is only applicable to a shutdown where production is stopped during the process to allow therepair or upgrade to occur.Another consideration is product loss. The type of product determines cost significance. This is relevantfor both a shutdown and a hot tap since the section of the line under construction needs to be emptiedbefore work can be done. The amount of product emptied for a hot tap is significantly less than forshutdown. A liquid product can, in most cases, be recovered and reintroduced into the system. This is,typically, not possible for a gas which is vented to the atmosphere. In addition, for gas products,purging is required, which adds an additional cost to the procedure, more so for the shutdown than forhot tapping. Two approaches can be used to account for the loss of production and product;a)b)the losses can either be included as additional costs for the shutdown procedure, orit can be listed as a benefit of the hot tapping procedure.It is, however, important that this cost/benefit is not accounted for twice.Even though this article attempts to discuss a general procedure, individual operators are advised toconsider company records and consult a hot tapping specialist when doing a cost-benefit analysis.Each pipeline and system are unique and may have additional factors that need to be accounted for.5 ION Pro Services 2020
2. LINE REPAIR CASE STUDYThe best way to illustrate how to conduct a cost-benefit analysis is by means of a simple example. Thecase study below describes a simplified and theoretical case in which either hot tapping or a shutdowncould have been employed to repair a defect in a liquid pipeline. Costs that would differ based on thetype of product (liquid vs. gas) are also highlighted.Note that no real-world case will ever be this simple. The purpose it to illustrate the philosophy at play indetermining the most suitable method for pipeline repair work.2.1BACKGROUNDCompany A is a gasoline supplier that operates a 30-mile gasoline pipeline between two cities. Duringroutine pipeline inspections, a defect was detected in the 8" pipeline that needs to be repaired toprevent a leak and contamination of the surrounding area. A 15 ft section of pipe needs to be replaced.The pipeline section was evaluated, and it was confirmed that only the 15 ft section needs to bereplaced and that the surrounding pipeline's condition and process parameters are suitable to enablehot tapping to be used for the repair.Company A is evaluating the most cost-effective meth
of hot tapping and shutdown procedures, use the above subcategories to calculate the cost of each. 1.3.2 HOT TAPPING COST BREAKDOWN In order to do a cost-beneﬁt analysis, the direct cost estimation for hot tapping needs to be completed. This is done at the start of a project and may
Hot and cold tapping procedures are covered below. 188.8.131.52 Hot Tapping For hot tapping, a specialized tapping machine is always required. In addition to the tapping sleeve and machine, the assembly consists of a branch valve (gate or ball) and the cutting device (see Figure 3)
After the hot tapping process the customer will connect the prefabricated and preinsulated new line with the preinsulated Shut-Off valves to the TONISCO Hot tapping Valve by welding. TONISCO hot tapping valves are designed to be used only once. After the new line is completed by hot tapping the sluice plate will be removed and the
To run through a successful hot tapping process, drilling and welding abilities are re-quired. Target systems in the industry of hot tapping are for instance cooling systems, district heating, gas and water distribution. (TONISCO. 2014a.) 2.1.1 About TONISCO Hot Tapping TONISCO developed several drilling devices for hot tapping.
A typical hot tap requires a: the hot tapping drill tapping saddle / clamp, ball valve. Hot tapping takes approximately 30-60 minutes, depending on the size of the hole and the pipe material. Note: Hot tapping can be dangerous and should be performed by experienced technicians only. Care should be taken when using the hot
polyatomic ions: a. amm onium ion b. sulfate ion c. sulfite ion d. carbonate ion e. nitrate ion f. permanganate ion g. hypochlorite ion h. phosphate ion i. cyanide ion j. hydroxide ion 9.2 Naming and Writing Formulas for Ionic Compounds A. _ Ionic Compounds 1. What are Binary Ionic Compounds? 2.
The T-37A tapping machine is designed for hot tapping while the existing pipeline is pressurized. Various cutter housings and cutter sizes and can be exchanged onto the tapping machine to perform a wide array of pipeline services including hot tapping and line stop
Hot Tapping Basic procedure Install fitting and valve on existing pipeline Install hot tap machine Perform hot tap through the open valve (special device retains the ‘coupon’ removed during the operation) Cutter assembly retracted Hot tap valve closed Hot tap machine removed to allow connection to new pipe 2 Hot Tapping is a specialist t
Introduction The three-year (2010-2013) ‘Fields of Britannia’ project, funded by the Leverhulme Trust, aims to explore the transition from Roman Britain to medieval England and Wales from a broad landscape perspective, reaching beyond the traditional site-based approach. One of the most distinctive features of the British landscape today is its intricate pattern of fields, and it is their .