1、BRITISH STANDARD BS 6886:1987 Specification for Alumino-silicate refractories for use in coke ovens UDC 666.9.041.014.762.1BS6886:1987 This British Standard, having been prepared under the directionof the Refractory Products Standards Committee,was published underthe authority of the BoardofBSI and
2、comes into effecton 30September1987 BSI 01-2000 The following BSI references relate to the work on this standard: Committee referenceRPM/10 Draft for comment86/37895DC ISBN 0 580 16126 9 Committees responsible for this BritishStandard The preparation of this British Standard was entrusted by the Ref
3、ractory Products Standards Committee (RPM/-) to Technical CommitteeRPM/10, upon which the following bodies were represented: British Ceramic Research Ltd. British Coal British Metallurgical Plant Constructors Association British Steel Industry Coke Oven Managers Association Institute of Refractories
4、 Engineers Refractories Association of Great Britain Amendments issued since publication Amd. No. Date of issue CommentsBS6886:1987 BSI 01-2000 i Contents Page Committees responsible Inside front cover Foreword ii 1 Scope 1 2 Definitions 1 3 Classification 1 4 Sampling 1 5 Inspection 1 6 Chemical co
5、mposition and physical properties 1 7 Dimensional tolerances 4 8 Appearance 4 Appendix A Testing 6 Appendix B Thermal spalling test for checker bricks 6 Appendix C Distribution of brick sizes within the tolerance band 7 Figure 1 Permitted edge damage on classA faces 5 Figure 2 Permitted corner damag
6、e on classA faces 5 Figure 3 Permitted edge damage on classB faces 5 Figure 4 Permitted corner damage on classB faces 5 Figure 5 Permitted edge damage on classC faces 5 Figure 6 Permitted corner damage on classC faces 5 Table 1 Schedule of composition and physical properties whenselectionisbased on
7、procedures using a guaranteed value for the mean 2 Table 2 Schedule of composition and physical properties whenselectionisbased on procedures employing a guaranteed value limit 2 Table 3 Test limit values 3 Table 4 Schedule of additional relevant properties 3 Table 5 Tolerances on linear dimensions
8、4 Publications referred to Inside back coverBS6886:1987 ii BSI 01-2000 Foreword This British Standard has been prepared under the direction of the Refractory Products Standards Committee. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Stan
9、dards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pagesi andii, pages1to8, an inside back cover and a back cover. This stand
10、ard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.BS6886:1987 BSI 01-2000 1 1 Scope This British Standard specifies the chemical and physical requirements and dimensional tolerances for alumino-
11、silicate refractories that in the fired state contain30% to45% alumina, and are for use in coke oven construction. It specifies the methods of sampling, testing and analysis to be used for bricks and shapes of alumino-silicate material. NOTEThe titles of the publications referred to in this standard
12、 are listed on the inside back cover. 2 Definitions For the purposes of this British Standard, the definitions given inBS3446 apply together with the following. surface crazing a rectilinear network of fine hairline microcracks, generally intergranular and entirely confined to within5mm of the brick
13、 face NOTEIt is not usually visible to the naked eye on clean as-fired brick faces, but is revealed lay a surface cover of dark powder or dust. 3 Classification 3.1 Three classes of alumino-silicate refractories are specified: CO40, CO35, and CO30, defined by the properties given inTable 1,Table 2 a
14、ndTable 3. 3.2 Three categories of brick are defined by differences in manufacturing processes and/or sizes; category1 bricks are dry or semi-dry pressed, category2 bricks are plastic moulded, and category3 bricks are of large dimensions or mass(400mmon any dimension or25kg). 3.3 For the purposes of
15、 this British Standard, the faces of the bricks are classified as follows: class A: faces in contact with the coal; class B: faces in contact with the gases; class C: other faces. NOTEClassification of the faces is designated by the customer and bricks may have a combination of classified faces. 4 S
16、ampling Sampling shall be carried out in accordance with a suitable sampling plan such as one of the methods described in BS6065. NOTE 1Any other sampling plan should be agreed between the manufacturer and the purchaser. NOTE 2When a sampling plan from BS6065 is used, it is necessary to state whethe
17、r the acceptance is to be based on either a mean value with a standard deviation or a limiting value accompanied by an acceptable quality level(AQL). NOTE 3Guidance on the use ofBS6065 is given in BS6434. 5 Inspection An area illuminated to a minimum of500lx shall be provided for inspection purposes
18、. 6 Chemical composition and physical properties 6.1 General The composition and physical properties of alumino-silicate refractories shall be as given inTable 1 orTable 2 andTable 3, and inTable 4, when tested in accordance with the methods given inAppendix A. 6.2 Control properties The control pro
19、perties used for acceptance testing in accordance with BS6065 (or other agreed plan) shall be selected from those shown inTable 1. The values of limit, designated upper limitT sand lower limitT iinTable 2, are based on an AQL of4% and shall be used in conjunction with the procedures inBS6065. NOTE 1
20、No statistical limit value is given for the cold crushing strength; for this test only, an actual test limit is given inTable 3. NOTE 2Wherever possible, a maximum of three control tests should be agreed. Bulk density and apparent porosity should not be selected as two separate control properties. 6
21、.3 Additional relevant properties NOTE 1For each specific application of alumino-silicate refractories within the coke oven, additional properties are required. Refractories for each of the applications listed inTable 4 shall comply with the requirements given for that application, when tested in ac
22、cordance with the methods given inAppendix A. NOTE 2As the tests required for measuring these supplementary properties are either of long duration or otherwise expensive to perform, such tests may be carried out under reduced inspection procedures agreed between manufacturer and purchaser. Such redu
23、ced schedules may be taken fromBS6001 orBS6002. The appropriate limiting values shall be as given inTable 4, and shall be irrespective of the class or category of the brick as designated inTable 1, Table 2 andTable 3.BS6886:1987 2 BSI 01-2000 Table 1 Schedule of composition and physical properties w
24、hen selection is based on proceduresusingaguaranteed value for the mean a Table 2 Schedule of composition and physical properties when selection is based on procedures employing a guaranteed value limit a Properties Coke oven refractory material class CO40 CO35 CO30 Mean () Standard deviation ( ) Me
25、an () Standard deviation ( ) Mean () Standard deviation ( ) Chemical composition (%) masson an ignited basis Al 2 O 3 Fe 2 O 3 K 2 O+Na 2 O 41.5 2.5 1.0 0.9 0.3 0.3 37.5 3.0 1.5 1.3 0.3 0.3 32.5 3.0 1.5 1.3 0.3 0.3 Bulk density (kg/m 3 ) Category1 Category2 Category 3 2100 2050 2000 50 50 50 2050 20
26、00 1900 50 50 50 1950 1900 1850 50 50 50 Apparent porosity (%) Category1 Category2 Category3 20 22 24 1.3 1.3 1.3 22 24 28 1.3 1.3 1.3 27 30 32 1.3 1.3 1.3 Cold crushing strength (N/mm 2 ) Category1 Category2 Category3 25 22 20 8 8 8 22 19 17 8 8 8 22 19 15 8 8 5 Permanent linear change (%) after2h
27、(at1410 C) (at1410 C) (at1250 C) Category1 Category2 Category3 0.40 0.40 0.70 0.05 0.05 0.05 0.50 1.00 1.25 0.10 0.10 0.15 1.00 1.25 1.50 0.20 0.20 0.20 a The mean () and the standard deviation ( ) as used in the tables represent the mean and the standard deviation of the population as a whole. The
28、sample mean () and the sample standard deviation (s) may be related to the values in the table by procedures described in BS6065. Properties Coke oven refractory material class Limit (i=min. s=max.) CO40 CO35 CO30 Limit (T) Standard deviation ( ) Limit (T) Standard deviation ( ) Limit (T) Standard d
29、eviation ( ) Chemical composition (%) mass on an ignited basis Al 2 O 3 Fe 2 O 3 K 2 O+Na 2 O 40 3.0 1.5 0.9 0.3 0.3 35 3.5 2.0 1.3 0.3 0.3 30 3.5 2.0 1.3 0.3 0.3 i s s Bulk density (kg/m 3 ) Category1 Category2 Category3 2000 1950 1900 50 50 50 1950 1900 1800 50 50 50 1850 1800 1 750 50 50 50 i i i
30、 Apparent porosity (%) Category1 Category2 Category3 22 24 26 1.3 1.3 1.3 24 26 30 1.3 1.3 1.3 29 32 34 1.3 1.3 1.3 s s s Permanent linear change(%) after2h (at1410 C) (at1410 C) (at1250 C) Category1 Category2 Category 3 0.60 0.60 1.00 0.10 0.10 0.15 0.70 1.20 1.50 0.10 0.10 0.15 1.35 1.60 1.85 0.20
31、 0.20 0.20 s s s a See note toTable 1. xBS6886:1987 BSI 01-2000 3 Table 3 Test limit values Table 4 Schedule of additional relevant properties Property Coke oven refractory material class CO40 CO35 CO30 Mean Test limit Mean Test limit Mean Test limit Cold crushing strength (N/mm 2 ) Category1 Catego
32、ry2 Category3 25 22 20 15 15 12 22 19 17 15 15 12 22 19 15 15 15 12 Application Supplementary tests Mean () Limit (T) (i=min. s=max.) Sole-flue and regenerator Refractoriness-under-load Rising temperature test using a loadof0.2MN/m 2 a T 0.5 1315 C T 5.0 1415 C 1280C(i) 1380C(i) Thermal spalling res
33、istance Temperature1000 C to20 C in air Number of complete cycles W 25 20(i) Oven roof brick Refractoriness-under-load Rising temperature test using a loadof0.2MN/m 2 T 0.5 1315 C T 5.0 1415 C 1280C(i) 1380C(i) Oven sole paving bricks Abrasion resistance Abradability index on skin Abradability index
34、 on interior u 100 u 200 120(s) 235(s) Refractoriness (pyrometric cone equivalent) (PCE) 1670 C 1650C(i) Ascension pipe lining bricks Refractoriness (PCE) 1630 C 1610C(i) Coke wharf bricks and batterypaving Abrasion resistance Abradability index on skin Abradability index on interior u 100 u 200 120
35、(s) 235(s) Oven jamb bricks Thermal spalling resistance Temperature1000 C to20 C in air Number of complete cycles W 25 20(i) Abrasion resistance Abradability index on skin Abradability index on interior u 100 u 200 120(s) 235(s) Checker bricks Reversible thermal expansion The mean coefficient of exp
36、ansion 0 C 1000 C u 5.5 10 6 6.5 10 6 (s) b Thermal spalling resistance Temperature350 C Number of complete cycles W 20 15(i) Oven door Thermal spalling resistance Temperature1000 C to 20 C in air Number of complete cycles W 25 20(i) Refractoriness (PCE) 1630 C 1610C(i) NOTEThe purchaser may require
37、 resistance to carbon monoxide attack for certain areas of the coke oven, but the requirements are outside the scope of this standard. a T 0.5andT 5.0relate to temperature and should not be confused with limit (T). b SeeAppendix B.BS6886:1987 4 BSI 01-2000 7 Dimensional tolerances 7.1 Linear dimensi
38、onal tolerances shall be as given inTable 5, when tested in accordance with the methods given inAppendix A. The calculated values of tolerance shall be rounded up to the next millimetre. NOTE 1An agreed sampling procedure (seeclause4) should be adopted when checking dimensions of each batch of brick
39、s. If a plan for sampling by attributes is used, an AQL should be agreed, as described inBS6065. NOTE 2The control dimensions, used for acceptance testing in accordance with BS6065 (or other agreed plan) should be selected by agreement (seealso6.2). Wherever possible, a maximum of three control dime
40、nsions should be agreed. NOTE 3The grouping of bricks into size intervals (size banding) may be found helpful for certain shapes. The distribution of bricks within the upper and lower limits of the tolerance should be such that a satisfactory construction is possible (seeAppendix C). 7.2 At the requ
41、est of the customer, the manufacturer shall provide a production control chart, or histogram, of inspected and measured controlled dimensions for each batch presented for inspection. Table 5 Tolerances on linear dimensions 8 Appearance 8.1 General The following requirements relating to the appearanc
42、e shall not be taken as representing the average quality of the batch, but only as a means of defining acceptance limits. NOTE 1An agreed sampling plan (seeclause4) should be adopted for checking the appearance of each batch of bricks. If a plan for sampling by attributes is used, an AQL should be a
43、greed, as described in BS6065. NOTE 2The bricks should be compact and of evenly burnt homogeneous structure; they should have full firm corners and all arrises and tongues should be firm and strong. When broken, bricks should show an even texture and be free from deleterious cracks, voids and lamina
44、tions, and signs of incorrect firing. 8.2 Limits on defects of external appearance 8.2.1 General. Limits of defects of external appearance shall comply with8.2.2 to8.2.6, when tested in accordance with the methods given inAppendix A. 8.2.2 Damage to corners and edges. The maximum permissible dimensi
45、ons of damage to the corners and edges ofA,B andC faces shall be as shown inFigure 1 toFigure 6. Defects to corners and edges shall be separated by a minimum distance of25mm. Where faces of different classes adjoin on a brick, the maximum permissible dimensions of damage to the corners and edges whe
46、re they join shall be as shown for the highest class face. In this connectionA shall be the highest class face andC the lowest class face. 8.2.3 Maximum number of defects per brick. The maximum number of defects per brick shall be as follows: a) class A face: 1edge and1corner defect; b) class B face
47、: 1edge and1corner defect; c) class C face: 2edge and2corner defects. Where a classC face adjoins a classA orB face, the maximum number of defects shall be in accordance with the requirements of the higher class face. NOTEManufacturers identification marks should be on classC faces wherever possible
48、 and should not be on classA faces. 8.2.4 Cracks. The maximum crack length shall be as follows: a) class A face:25mm for any one crack with the total sum of crack lengths on the face not exceeding50mm; b) class B face:50mm for any one crack with the total sum of crack lengths on the face not exceedi
49、ng100mm; c) class C face:75mm for any one crack with the total sum of crack lengths on the face not exceeding150mm. For a continuous crack extending over two or more faces, the length on any classified face shall not exceed the limits stated above and the total length shall not exceed50mm. NOTESurface crazing is not detrimental to the performance of the brick in the coke oven and is acceptable. 8.2.5 Craters. The maximum dimensions for craters shall be as f
