3.3 Typical Lining Structure
3.3.1 The lining structure of equipment or piping with diameter up to 500mm after lining should be designed by sections and shall be constructed by sections.Each section should be 1000mm long，shall adopt socket-and-spigot structure at both ends，and shall comply with the following requirements:
1 Double layer heat-insulating and abrasion-resistant lining with hexmesh shall be provided with back plate and socket bushing［see Figure 3.3.1（a）］；
2 Single layer or double layer heat-insulating and abrasion-resistant lining without hexmesh shall be provided with socket bushing［see Figure 3.3.1（b）］；
3 Double layer heat-insulating and abrasion-resistant lining without hexmesh shall be provided with socket bushing［see Figure 3.3.1（c）］；
4 The maximum clearance of lining sections at the joint should be 6mm.
5 Assembly welding shall be made after lining heat drying is completed by sections，and refractory ceramic fiber blankets shall be filled between the back plates at the joint.
Figure 3.3.1 Schematics of Socket Structure at Joints of Lining Sections
1—Equipment or piping；2—Connecting plate；3—Back plate；4—Refractory ceramic fiber blanket；5—Socket bushing；6—Fixed bushing；7—Lining back plate；8—Fixing plate
3.3.2 Fixing plate shall be provided at the joint between hexmesh and lining back plate of double layer heat-insulating and abrasion-resistant lining with hexmesh，the width of fixing plate should be within 30mm～50mm，and the thickness of fixing plate should be 6mm.Fixing plate shall be welded with lining back plate，and hexmesh shall be welded with fixing plate and lining back plate（Figure 3.3.2）.
Figure 3.3.2 Schematics of Hexmesh Welded with Fixing plate and Lining Back Plate
1—Lining back plate；2—Fixing plate；3—Abrasion-resistant concrete；4—End plate；5—Hexmesh；6—Heat-insulating concrete；7—Cylindrical anchor
3.3.3 Fixing plate or lining guard disc shall be provided at the location where the inserted pipe or component in double layer heatinsulating and abrasion-resistant lining with hexmesh intersects with hexmesh，and the inserted pipe or component shall be welded with hexmesh.And the following requirements shall be followed:
1 If the nominal diameter of inserted pipe is larger than or equal to 100mm，fixing plate shall be installed inside hexmesh［Figure 3.3.3（a）］；
2 If the nominal diameter of inserted pipe is less than 100mm，lining guard disc shall be installed outside hexmesh［Figure 3.3.3（b）］.
3.3.4 Expansion joints（figure 3.3.4）shall be provided for the lining back plate located at the interior wall of double layer heatinsulating and abrasion-resistant lining and single layer heat-insulating and abrasion-resistant lining without hexmesh where manholes，loading/unloading holes and openings of inserted pipes are designed，and shall comply with the following requirements:
Figure 3.3.3 Attachment of Hexmesh and Inserted Pipe
1—Wall；2—Insert；3—Cylindrical anchor；4—Heat-insulating concrete；5—Abrasion-resistant concrete；6—Hexmesh；7—Lining guard disc；8—Fixing plate；9—End plate
Figure 3.3.4 Schematics of Lining Back Plate
1—Lining back plate；2—Hexmesh fixing plate
1 Lining back plate without notches on its rim shall be used for the openings in nominal diameter less than 450mm.
2 Lining back plate with notches on its rim shall be used for the openings in nominal diameter equal to or larger than 450mm.
3 Hexmesh fixing plate shall be discontinued at expansion joint of lining back plate where hexmesh fixing plate meets.
4 The expansion joints and the notches on the rim of lining back plate shall be arranged evenly around disc circumference，and shall comply with the following requirements:
1）b value should be taken as 150 to 230mm；
2）c value should be taken as B/3，and it may be taken as 20mm；
3）R value should be taken as 40 to 60mm.
3.3.5 The pipe or component inserted in heat-insulating and abrasion-resistant lining without hexmesh shall be wrapped with refractory ceramic fiber paper，and shall be installed with lining guard disc.If the width of lining guard disc is larger than 50mm，expansion joints shall be cut in the guard disc（see Figure 3.3.5），and shall comply with Item 4 in Article 3.3.4 of this Code.Binding thickness of refractory ceramic fiber paper wrapped over the inserted pipe or component shall conform to Table 3.3.5.
Figure 3.3.5 Inserted Pipe Wrapped in Ceramic Fiber Paper
1—Lining guard disc；2—Refractory ceramic fiber paper；3—Inserted pipe or component
Table 3.3.5 Binding Thickness of Refractory Ceramic Fiber Paper Wrapped over Inserted Pipe or Component（mm）
