3.4　Packer

3.4.1　If packer size and setting are stipulated by technical design document，shall comply with the design document.

3.4.2　Before construction，packer arrangement layout shall be drawn out in accordance with equipment process layout，equipment foundation bolts layout and external dimension of equipment base plate；packer dimension and quantity shall be determined based on equipment load，bolt fastening force and foundation concrete compressive strength.Packer setting shall meet the requirements of current national standard，i.e.，"General code for construction and acceptance of mechanical equipment installation engineering"（GB 50231）.

3.4.3　Grinding method for packer installation shall be in accordance with the following requirements:

1　Laitance shall be removed on foundation surface，and packer setting place shall be chiseled and grinded for flat ground.

2　Packer shall be placed securely and neatly；the contact points between packer and foundation shall be well distributed；the contacting surface between packers or between equipment base plate and packer shall be ensured tightly and firmly.

3　Packer group should be composed by one piece of flat packer and a pair of wedge packers.Put the wedge packer on the flat packer，and each packer group shall not exceed 5 pieces.

3.4.4　Grouting method for packer installation shall be in accordance with the following requirements:

1　For fabrication of large dimension of flat packer，exhaust hole in the middle shall be designed.

2　Grouting materials shall be strictly measured during grouting.At the same time make a set of concrete test blocks whose 48h compressive strength shall reach the design strength for the foundation concrete.The test report shall be provided.

3　The elevation for packer seated in the grouting material shall be determined in accordance with equipment installation elevation and the combination height of wedge packers which shall be calculated as per 0.75 L（L-means the length of the packer）.

4　The installation accuracy for packer seated in grouting material shall be in accordance with those specified in Table 3.4.4:

Table 3.4.4　Installation accuracy for packer seated in grouting material

Notes:1　Level Ⅰ accuracy:refers to the equipment base plate has been fabricated；equipment installation requires high-accuracy，especially continuous production line and the most strictest correlated equipment，such as rolling mill，uncoiler，hot coil box，coiler，welding machine and etc.
2　Level Ⅱ accuracy:refers to the equipment base plate has or not been fabricated；equipment installation requires high-accuracy，especially continuous production line and more stricter correlated equipment such as pickling tank，roller table and in and out furnace equipment and etc.
3　Level Ⅲ accuracy:refers to equipment base plate has not been fabricated，and low accuracy installation required，such as furnace structure，process structure，platform and etc.

5　The specification and size for grouting mould box shall be determined in accordance with the burying requirements for grouting packer（Figure 3.4.4），and mould box should be manufactured by 6mm thick checkered plate.

Figure 3.4.4　Sketch of burying requirement for grouting packer

Note:L，B is length and width for flat liner respectively