4.2 Boiler Steel Frame and Related Accessories
4.2.1 The scope and the construction preparations of the waste heat boiler steal frame and the related accessories shall be in accordance with the following requirements:
1 The boiler steel frame shall include column，girder，top board，truss，and backplate frame，related accessories shall include sealing parts，platforms，ladders，boiler door，boiler wall components；
2 Physical dimension of boiler steel frame and related accessories shall be measured and rechecked by the measuring instruments，which are certified to be qualified by metrological service department；
3 Before installation，the boiler steel frame and the related accessories shall be counted according to the supplier's product list，packing list，and drawings，and the chief components are required to carry out the following checking:
1）The physical dimension of the chief components of the steel frame shall comply with the regulation of equipment technical documentation，and the allowable deviation for rechecking shall comply with the regulation of Table 4.2.1；
Table 4.2.1 The allowable deviation of chief component for steel frame rechecking
Table 4.2.1（Continued）
Note:The frame includes backplate frame，top board frame and other rectangle frame.
2）The appearance shall be checked wheather has corrosion，cold-lap，cracks，and weld defects；
3）Except the low alloy steel，other alloy steel parts shall be spectrum rechecked one by one.
4 The boiler steel frame and the related accessories have no bump，cracks，and damages after being adjusted；when the ambient temperature is lower than-20℃，it is not allowed to adopt rapping method to carry out cold state adjustment；
5 When the hot state adjustment is carried out to the boiler steel frame and related accessories，it is better that the heating temperature of carbon steel should not exceed 850℃and the heating temperature of alloy steel should be lower than the steel critical temperature Acl.
4.2.2 The checking and measuring of the boiler foundation shall be in accordance with the following requirements:
1 Before the boiler and the auxiliary equipment are set up，the rechecking of the equipment foundation location and physical dimension shall comply with the regulations of Table 12.8.2-1 and Table 12.8.2-2；
2 Before the boiler equipment is installed，the installation datum lines of longitudinal and horizontal and the elevation datum point shall be confirmed；
3 When the measurement is carried out to the boiler equipment foundation，the center lines of longitudinal and horizontal shall be mutually perpendicular；the allowable deviation of the location center lines separation distance of two adjacent columns shall be±2mm；the length difference of two diagonals of the location center point of 4 symmetry columns shall not be larger than 5mm.
4.2.3 The structural component fabrication of the boiler steel frame shall be in accordance with the following requirements:
1 Columns joint and steel frame fabrication shall be carried out on the stable fabrication frame，which shall be aligned；
2 When combining boiler steel frame，for the supporting structure，the 1m elevation line of the columns should be confirmed as per the chief clevises elevation together with the elevations of most clevises and capital elevation；for the suspension structure，the 1m elevation line should be confirmed as per the elevation of the main girder of the top board or the capital elevation；
3 The boiler steel frame fabrication shall be carried out as per the weld sequence required by equipment technical documentation，and the weld shrinkage allowance shall be available；
4 The allowable deviation of the boiler steel frame assembly installation shall comply with the regulation of Table 4.2.3.
Table 4.2.3 The allowable deviation of the boiler steel frame assembly installation（mm）
Notes:① The separation distance among all columns in supporting structure should be positive deviation；
② The allowable deviation of the elevation of girders of supporting drum，economizer，superheater shall be 0-3 mm；requirement for rigid platform installation is same with the girder；
③ Separation distance among girders of top board indicates the separation distance among the center line of suspension hole formed among girders.
4.2.4 Boiler steel frame installation and secondary grouting shall be in accordance with the following requirements:
1 When level the steel frame installation，according to the elevation datum line on boiler operation layer，measure the 1m elevation line of every column.The 1m elevation line of the column shall be the datum grade of boiler components and parts installation and inspection；
2 One layer（or section）of the steel frame shall be aligned after being installed，forbid carrying out next process installation on the unaligned steel frame；
3 While carrying out boiler steel frame welding，firstly leveling and fixing with spot welding，proper weld shrinkage allowance shall be available and the dimension shall be rechecked，after all requirements are met，formal welding can be carried out as per welding sequence；
4 After the steel frame hoisting is carried out，recheck the column perpendicularity，main beam deflection，and the main dimension of all parts；the frame shall be stable after the steel frame hoisting is set up；
5 The allowable deviation of steel frame installation shall comply with the regulations of Table 4.2.4:
Table 4.2.4 Allowable deviation of steel frame installation（mm）
Notes:① The distance among all columns in supporting structure should be positive deviation；
② The allowable deviation of the elevation of girders of supporting drum，economizer，superheater shall be 0-3 mm；requirement for rigid platform installation is same with the girder；
③ Separation distance among girders of top board indicates the distance among the center line of suspension hole.
6 The platforms and ladders should be installed synchronously with the steel frame；
7 The columns of the handrails shall be vertical with average distance，and there is at least one column at the bent；the columns of the handrails of every layer and platform of same side should be at the same perpendicular line.After being installed，the platforms，handrails，ladders，columns，coamings shall be fixed welded with smooth joints；
8 It shall not cut randomly on the platforms，ladders and the supports；
9 Outer backplate shall not be distorted and damaged by impacting，the joint line should be straight，and the joints shall be fastened；
10 After the steel frame is aligned，the column footings shall be fixed on the base according to the equipment technical documentation.When the column footing is fixed by rebar welding，the rebar shall be heated to bend and clung to the footing reinforcing rib，and double sides welding shall be applied，the weld joint length shall be 6 times-8 times of the rebar diameter；
11 When the column footing is fixed by the anchor bolt or regulated by bolt，the boiler foundation shall be carried out with secondary grouting after the first layer of steel frame is aligned；when the column footing is fixed by the rebar welding，the boiler foundation can be also carried out with secondary grouting after the boiler chief equipment hoisting is finished；
12 Before secondary grouting，the gasket iron are welded，the construction to anchor bolts and rebars have been completed，oil dirt，welding slag，and debris shall be removed from the foundation surface；
13 Before secondary grouting，carry out checking and acceptance to the concealed works，and the acceptance record for concealed works shall be filled in as per the Table 3.3.4 of this code，the certificates shall be issued by every party；
14 Boiler equipment secondary grouting shall comply with the regulation of Article 12.5.5 of this code.
4.2.5 The installation of manhole door and boiler wall components shall be in accordance with the following requirements:
1 The surface of the manhole door shall be smooth without cracks，scars，and blow holes；the operation shall be flexible and the junction surface shall be tight；
2 Gland packing shall be applied to the sealing surface of the manhole door connected by bolt；the fixed bolt head of the doorframe shall be full welded to the inside of boiler wall，after the bolt is tightened，2-3 screw pitches of the screw shall be outside together with the nut；
3 The manhole door and the related components shall be installed together with the backplate，and the insulating layer of the manhole door is completed；
4 Boundary dimension and material of the boiler wall components shall comply with the equipment technical documentation；the appearance of the boiler wall components shall be well without defects，such as cracks and scars；while installing boiler wall components，the expansion clearance shall be remained as per the equipment technical documentation.
4.2.6 The installation of boiler sealing elements shall be in accordance with the following requirements:
1 The installation shall be carried out as per the sequence，and while installing the testing casing pipe and manhole device，the installation position can be adjusted as per practical situation；
2 The junction surface and the bolt installation of the sealing device fixed by bolt shall comply with the regulation of the clause 2 of Article 4.2.5 of this code；
3 The weld joint of ventilation girder shall be tightness without leakage，and the ventilation channels shall be unblocked.
4.2.7 Rain-proof shed of the boiler and the pipeline perforation on the roof of the protection cell shall be equipped with flashing.