定期关闭工艺单元（称为周转）定期发生在工业设施中。周转允许需要单元离线的任务。由于在延长中断期间的收入损失，因此对周转的计划必须确保任务尽可能有效地完成。

通常，在周转期间发生了两种类型的任务：资本项目的维护和完成。新利18备用网址与维护不同，基本项目通常在关闭之前开始。新利18备用网址与设备，管道以及电气和仪表系统的搭配最常在工厂中断期间进行并完成。

资本项目可能是确新利18备用网址定关闭大小的重要因素。这就是为什么在谈论周转费用时应考虑两种成本的原因新利18备用官网登录：

• 由于中断而失去收入。连续运营的工厂的每个离线日都有与之相关的高成本。如果减少周转范围缩短离线天数，则节省可能是非凡的。
• 施工费用。在周转期间，由于几个因素，建筑成本的运行要高得多，包括由于劳动力密度较高新利18备用官网登录和在变化期间的过渡时间较长，生产率较低。此外，全天候工作需要以高级成本的高度加班。此外，由于增加的行政任务和额外的计划，间接的施工成本往往新利18备用官网登录会增加。

The most important step in reducing turnaround scope is alignment of all stakeholders on the project. This activity should start from project kickoff and continue throughout.

Turnaround Scope Reduction

根据每个项目的特定情况，用于管理周转范围的技术将有所不同。这是适用于每个项目的一些建议。

• 隔离。工艺单元中的许多管道组件，设备和仪器均设计允许隔离以进行维护。这些设计也可以用于执行资本项目搭配。

通常，在项目计划中包括进行搭配的隔离；但是，由于与运营小组缺乏协调性以及对孤立能力的不良假设，这种策略通常无法完全实施。设计团队应与工厂运营小组合作，审查每个搭档，并探索隔离的最终搭配的可行性。

• 热水龙头和仪器热剪。Hot-tap process, which allows for safely cutting into a pressurized stream, can help tie into an existing pipe system. Also, in the electrical and instrumentation arena, hot-cutover techniques are used to migrate new systems in multiple phases. Planners should compare the costs of online tie-ins versus performing them during a turnaround.
• 使用调查最小化现场制造。是常见的做法rt of a piping job is designated as field fabrication because of the difficulty in identifying obstacles such as existing structural steel and cable trays. When such obstacles can’t be located, field routing becomes the preferred way to avoid making field modifications on pipe that was fabricated off site. But for a turnaround project, all efforts should be made to do fabrication before the turnaround. This means gathering enough as-built information via surveying techniques such as 3D laser scanning to determine piping routes and fabricate around them accordingly.
• 优化间距以避免周转拆除。Some work may be scheduled for turnaround due to a lack of space in the plant and the need to demolish existing piping and equipment. However, the design team should conduct value engineering for building the new assets without removing key parts of an operating unit.

理想的情况是在周转之前安装新设备或管道。在周转期间，服务外资产是断开连接的，如果需要，可以在启动后拆除。

• Utilizing unplanned shutdowns。由于业务连续性对于连续运营的工业设施很重要，因此大多数工厂的可靠性足够高，可以最大程度地减少不期望的中断。但是，计划外的关闭偶尔会发生，并可以为资本项目提供搭配机会。新利18备用网址

The key to utilizing these outages is to plan for the unplanned. To this end, the project-execution team should closely track the progress of engineering and procurement. As soon as a construction work package is finalized and its materials are available, the team is ready to carry out the work when a shutdown opportunity occurs.

• 将范围转移到后范围。不t everything associated with turnaround scope must finish before start-up. With proper planning, certain activities can be postponed until after the turnaround, providing that the safety of plant operations and construction are not compromised. Post-turnaround activities include paint, insulation, fireproofing, heat tracing (if the turnaround completes during warm weather), and noncritical structural and civil items.

Every minute spent on turnaround planning has a significant potential for savings.

Fluor Corp.项目经理Houman Payami拥有10多年的能源，化学和电力行业的项目执行经验。他可以接触到houman.payami@fluor.com。