Removable Tube  Heat Exchanger

Introduction

Tube removal a process that involves cutting tubes, pulling out tubes and tube stubs, and even knocking tubes out of the vessel. You can look to Elliott for all your tube removal needs ranging from tube cutters to tube tuggers to pneumatic hammers. The tube removal process includes several process steps that must be performed with critical sequencing and tolerances. The initial step of our process the Tungsten Inert Gas shrinking of the tube to-tube sheet expansion joints where applicable, which performed with our plug removal TIG system.

Specifications of Removable Tube Sheet Heat Exchanger:

• The Removable Tube Sheet Heat Exchanger process carefully monitored for power and travel so that only designated areas in the tube are shrunk. Some tubes with minimal tube sheet contact, shrinking not required.

Applications of Removable Tube sheet Heat Exchanger:

• Tube Removers-One or a combination of the three below methods is used to remove a tube from a boiler or chiller vessel
• Tube Cutters-Tube Cutters are used to internally cut from the inside to the outside of the tube behind the tube sheet on one end. This lessens the force required to pull a tube. To eliminate tube cutting chips in the vessel, tubes should be scored and not totally cut through. The tube cutter needs to have sufficient reach to cut behind the tube sheet. Proper lubrication and cutting speed will increase cutting blade life.
• Tube Pullers-Used to break the seal and pull expanded tubes from a tube sheet. A spear or expanding collet is inserted and engaged into the tube inner diameter. A ram or gun applies force to exert an extracting force on the tube. The power to pull the tube is generated manually or through an hydraulic pump. The hydraulic pump can be manually, electrically or pneumatically driven. The pulling force required will vary with the tube size and wall, the depth of the tube sheet and tube material.
• Pneumatic Hammers-Pneumatic Hammers are an alternative method to remove tube stubs from heat exchangers and boilers. Maintenance technicians use piloted knockout tools to avoid damage to the tube sheet. The knockout tool is inserted into the tube and the impact pneumatic hammer is actuated to punch out the tube stub.
• Tube Installation (Tube Expanders)- Tube Expanding is the art of reducing a tube wall by compressing the outer diameter of the tube against a fixed container such as rolling tubes into tube sheets, drums, ferrules or flanges. Construction of heat exchangers, boilers, and surface condenser tubes is mainly limited to copper, steel, stainless steel, and cast iron with exceptions such as the use of titanium in ultra high pressure vessel applications. To assure a proper tube joint, the tube wall must be reduced by a predetermined percentage dependent upon the material the tube is constructed

Features of Removable Tube Sheet Heat Exchanger:

• A Removable Tube Sheet heat exchanger is the most common type of heat exchanger in all Industries. Mostly used in higher-pressure and Higher Temperature applications.
• Materials Of Construction: Stainless Steel, Copper Alloys and Other material options available.

Advantages:

• Hard rolled and tubes the shrinking process necessary to relieve the radial stress between the tube and tube sheet.

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