GE的技术条件-对灰铁250大型汽缸体

铸冶艺人

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SPECIFICATION AND PROPERTIES tidw’--n‘Y
‘ITLL SPECIAL ALLOY GRAY IRON MAIN FRAME CASTINGS
1. SCOPE:
General Electric Material C50E69 identifies a special alloy gray iron
diesel engine ma.in frame casting, the condition of which is designated
as follows:
C50E69A - MAIN FRAME CASTING WITH NUT POCKETS - 37,500 psi minimum
tensile strength in heavy wall critical sections,
electric melt or electric holding furnace
C50E69B - MAIN FRAME CASTING WITHOUT NUT POCKETS - 32,500 psi
minimum tensile strength in heavy wall critical
sections, electric melt or electric holding furnace
2.
2.1
2.2
CHEMICAL COMPOSITION:
General: It is the intent of this specification to subordinate chemical
composition to mechanical properties and microstructure, however the
chemical composition shall be mutually agreed upon. No deviation from
the approved chemical composition shall be allowed without written
permission from General Electric. The approved chemistry shall be
agreed to by the foundry and General Electric.
Chemistry Recommendations
ELEMENT (WT. %) C50E69A C50E69B
Carbon Equivalent* 3.60-3.90 3.60-3.90
Carbon 3.05-3.30 3.05-3.30
Silicon 1.55-2.10 1.55-2.10
Manganese .65-1.10 .65-1.10
Phosphorus .090 Max. .090 Max.
Sulfur .030-.lOO .030-.lOO
Nickel .60 Max. .60 Max.
Chromium .20 Max. .20 Max.
Molybdenum .40-.60 .25-.35
Copper .40-.60 .25--35
Vanadium .05 Max. .05 Max.
Nitrogen 60-120 ppm
Lead
60-120 ppm
.005 Max. .005 Max.
Titanium .025 Max. .025 Max.
Tellurium .020 Max. .020 Max.
* C.E. = Total Carbon + l/3 (Si+P)
1 GEWERAL C50E69
TRANSPORTATION SY!ZEMS BUSINESS OPERATIONS s 2
SPECIFICATION AND PROPERTIES
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TITLE
SPECIAL ALLOY GRAY IRON MAIN FRAME CASTINGS I
3. MECHANICAL PROPERTIES:
3.1 General: It is the intent of this specification that the castings themselves
have the specified tensile strength. All castings to C50E69A
shall have a minimum tensile strength of 37,500 psi in the heavy wall
critical sections (nut pocket area - see Figure #2) of the casting. To
insure this strength level, cast-in-mold test bars shall meet the
tensile strength specified in Section 3.2.
3.2 Tensile Strength Requirements: The basis of acceptance for each main
frame casting shall be the tensile test results from the 6" x 6"
cast-in-mold test blocks. The location and sectioning of the test
block is shown on the individual frame casting drawings and in Figures
l-3 of this specification. These test bars shall meet the following
requirements in the 6" x 6" cast-in-mold block::
Designation Machined Location
C50E69A Mid-radius
C5DE69B u 8,
Tensile Strength
37,500 psi Minimum
32,500 psi Minimum
3.3 Hardness: It is necessary to control the hardness of the casting to
prevent machining problems. Hardness testing shall be done by the
Foundry and reported on the form in Figure #5. The casting and test
bar shall meet the hardness requirements in the areas indicated below:
241 HB Maximum on cylinder deck and pan rail.
269 HB Maximum on sides near crankcase doors.
170 HB Minimum on crankcase bearing boss.
4. MICROSTRUCTURE:
4.1 General: The microstructure, throughout the casting, shall consist of
predominantly Type A graphite in a pearlitic matrix. Non-standard
graphite type such as "Mesh" graphite shall not be acceptable i.n
amounts over 10% of the overall structure. Ferrite shall not represent
more than 5% of the overall structure.
4.2 Graphite Flake Size: The graphite flake size shall be predominantly
A.S.T.M. size 4 or finer.
size 2 or 3 is acceptable.
A small amount of A.S.T.M. graphite flake
Flake size shall be determined at the
mid-radius test bar location of the 6" x 6" cast-in-mold test block.
TSBO-20924 (9-91)
11 GENERAL ELECTRIC /
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SPECIFICATION AND PROPERTIES .wMrP-m-Y
:ITLL SPECIAL ALLOY GRAY IRON MAIN FRAME CASTINGS
4.3 Carbide Content: No chilled iron structure shall be allowed on the
machined surfaces of the casting. Intercellular carbides shall not be
allowed over 2% by volume. The intercellular carbide condition of the
casting shall be determined metallographically at the mid-radius test
bar location of the 6" x 6" cast-in-mold test block.
5.
5.1
MANUFACTURE:
General: Manufacturing methods and processes in the foundry for
casting the main frame and the systems for their control shall be
subject to approval by the General Electric Company. Casting quality
and dimensional tolerances shall be in accordance with the applicable
drawings. Castings shall have acceptable machineability on the main
frame machining line in the GE Grove City Plant.
5.2 Inoculation: The casting shall be inoculated in the ladle and in the
mold to obtain a fine graphite structure and reduce the tendency to
chill. The inoculation practice shall be approved during the qualification
process and not changed without written permission from General
Electric.
5.3 Times and Temperatures: The recommended pouring time is 60 seconds.
The recommended pouring temperature range is 2450-2500°F. A minimum
mold cooling time of 120 hours prior to shake-out is required.
5.4 Welding: No welding of any kind shall be permitted without specific
approval of General Electric Diesel Engine Engineering.
6. VENDOR QUALIFICATION
6.1 General: Qualification of a foundry to produce main frame castings to
C50E69A shall be based on achieving the minimum specified tensile
strength at the critical heavy wall nut pocket location in the castings
(see Figures 1 and 2). The trial frames shall be cast with the
6"~6"xl8" test block as shown in Figures 1 and 2. Tensile specimens
shall be cut from the critical location in the casting and from the
half radius position in the test block (see Figure 3). Tests shall be
made to determine the tensile strength correlation between the casting
and the test bars.
APPROVED
TBANSPORTATION SYSTEMS BUSINESS OPERATIONS
SPECIFICATION AND PROPERTIES .mQd-’W--‘-m-
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6.2 Foundry Process: The foundry process shall be developed to produce
main frame castings above the specified tensile strength level, with
the appropriate hardness and microstructure and consistent quality.
The process shall not be changed without permission from GE. Process
records shall be maintained at the foundry for the following:
1)
2)
3)
4)
5)
6)
7)
8)
Raw Material Charge - Proportion and quality of steel, returns,
scrap, pig iron, etc.
Melting Practice - Time and maximum temperature of melting process,
melting rate, hold time, control parameters, and tapping
temperature.
Alloying Practice - Timing, quantity and form of alloy additions,
stirring of ladle. Chemical composition check procedures. Temperature
adjustment procedures.
Inoculation Practice - Timing, quantity, form, metal temperature
and brand name of inoculant. Size and location of in mold
inoculant.
Pouring - Time from tap and inoculation, and pouring temperature,
rate, and duration.
Shake Out - Time since pour and metal temperature.
Cleaning - Cleaning and inspection procedure, time and intensity of
blast operations, documentation of authorized repairs, rust preventative
application.
Molding - Sand composition and binder system, washes and coatings,
dimensional control of cores and mold, sand QC procedure. Size,
material, and placement of chills. Casting feeding system, pouring
basin, slag control features, runners, gates, and risers. Geometry
and construction of cores and molds.
APPROVE0
TSBO-20924 (9-91)
GENERAL~ELECTRIC C50E69
TRANSPORTATION SYSTEhfS BUSINESS OPERATIONS s 2
SPECIFICATION AND PROPERTIES .(WZC-6m--d r-m
SPECIAL ALLOY GRAY IRON MAIN FRAK CASTINGS
7.
7.1
7.2
7.3
8.
8.1
8.2
8.3
9.
9) Quality Assurance - Positions and orientations of test bars for
tensile tests, hardness tests, and microstructure evaluation.
Tensile specimen design and test procedure. Sampling and test
procedure for chemical analysis. Sampling and test procedure for
process checks: liquidous carbon equivalent, chill wedge, etc.
ACCEPTANCE CRITERIA
Mechanical Properties: The main frame casting shall be accepted based
on the tensile strength minimums specified in Section 3.2. The tensile
test specimens shall be cut from the 6" X 6" cast-in-mold test block
from the location shown in Figures l-3. The foundry shall perform the
required tensile tests on each casting.
Hardness: The casting shall be accepted based on the surface hardness
ot the pan rail, cylinder decks, and crankcase door openings.
Microstructure: The casting shall be accepted based on the intercellular
carbide content and graphite flake size of the mid-radius of
the 6" x 6" test block (see Figure #3). A metallographic specimen may
also be taken from the Trepan or pan rail if deemed necessary by
General Electric.
REFEREE METHODS:
Tensile Testing-----------------ASTM-E8, using the specimen in Figure 4.
Brine11 Hardness ----------------A~M-ElO
Microstructure ------------------ASTM-A247
IDENTIFICATION:
The drawing and pattern number and cast date, and suitable identification
to designate the manufacturer shall be permanently marked on
each casting on the right-hand side of the front foot in the area where
this surface is not to be later machined. Any hand stamping shall be
in a non-critical area designated on the drawing.
APPROVED
BV R.F. Fischer
TSBO-20924 (s-91)
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SPECIFICATION AND PROPERTIES .mmm--d c-lu
TITLE
SPFCTAI Al I OY GRAY TRnN MATN FRAW CA%TTNr,q
10. TOLERANCES:
As indicated on the drawing and Applied Practices.
11. REPORTS:
11.1 The supplier of castings to C50E69 must submit a certificate of test on
the fon shown in Figure #5. The following data shall be reported:
a. Chemical analysis including total carbon, Si, Mn, S, P, Cu, Sn, Ni,
Cr, MO, V, Ti, Pb, Te, N (and other elements when added intentionally
as a process requirement, e.g., Mg or Ca, or suspected of
being present as residual tramp elements, e.g. Zn).
b. Carbon equivalent (by calculation).
c. Amount, type, and location of inoculant.
d. Time (clock reading) when inoculant is added to ladle.
e. Time (clock reading) when pouring from ladle to mold is begun.
f. Running time (elapsed time from metal entering sprue to the time
metal completely fills the mold).
4* Ladle temperature (measured by immersion thermocouple) and time at
which the readinq was taken. The recommended oouring temperature
range is 2450~250OOF.
h. Ladle identification (Serial No.).
i. Furnace identification (type, number, location,
j. Casting identification (Serial No. or cast date
k. Date casting poured.
etc.).
1.
1. Shake-out date (and time).
APPROVEO
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TRANSPORTATION SYSTEMS BUSINESS OPERATIONS
SPECIFICATION AND PROPERTIES .~culvlICr -,-_ lMl
SPECIAL ALLOY GRAY IRON MAIN FRAME CASTINGS
11.2
11.3
11.4
12.
518E
m. Chill as measured from a standard ASTM-A367 wedge; state which
wedge used (recormnended W3 or W4 from the ladle as final chemistry
is achieved).
n. Cast-in-mold test bar.
1) Tensile strength on the 6" x 6" x 18" bar.
2) Microstructure on the surface of the test bar from the
mid-radius of the 6" x 6" x 18" test bar.
0 Brine11 Hardness (HB)
1) Cylinder Deck and Pan Rail.
2) Crankcase Door Openings.
3) Crankcase Bearing Boss.
The remaining half of the cast-in-mold 6" x 6" x 18" test block,
properly identified, shall be shipped to General Electric Company with
each main frame casting.
Process control and conformance data including complete chemical composition
per Section 11.1 and microstructure per Section 4 shall be
maintained on file for a minimum of seven years by the vendor and shall
be supplied on request. All conformance data must be referenced to
frame casting serial number or cast dates.
Deviations from this specification or the applicable drawing must have
prior approval by General Electric Diesel Engine Quality Control on
Form TSBO-2795-A prior to shipment.
PROTECTIVE TREATMENT:
Main frame castings shall be protected against corrosion by an approved
crankcase rust preventive or paint as specified on the applicable
drawing.
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DATL OF
CONTINURD
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Figure 1. Main Frame Casting Test Bar Locations
APPROVED
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CONTINUED
GENERAL@ELECTRlC C50E69
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SPECIFICATION AND PROPERTIES
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SPECIAL ALLOY GRAY IRON b&IN FRAME.CASTINGS
PAN RAIL /
HARDNESS
BLIND RISERS
AS REQUIRED
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SPECIFICATION AND PROPERTIES .U.-d- ’--‘LLr
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SPFCIAI Al 1 OY GRAY IRON MAIN FRAMF CASWS
TENSILE TEST
SPECIMEN
DRAG SIDE
6X6X@
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COPE SIDE
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LINTER CELLULAR CARBIDE
8 GRAPHITE FLAKE SIZE
MEASURED FROM TENSILE
SPECIMEN
Figure 3. Acceptance Test Locations in Cast-On Test Bars
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ITLL SPECIAL ALLOY GRAY IRON MAIN FRAME CASTINGS
VENDOR NAME AND ADDRESS:
PURCH.ORDER # CASTING IDt T
PART NAME (8,12,16 CYL.MN.Fm DATE ! +I;E*OF
0 (CSTG SER.NO.OR DATE)
CAST
CASTINGW EIGHT SHAKE OUT DATE AND TIME
PATTERN NO. FURNACE IDENTIFICATION
LADLE IDENTIFICATION
I. FOUNDRY PROCESS
A. CHEMICAL COMPOSITION (WT. X)
C.E. C SI MN P S NI CR MO CU N
Sn V Ti Pb Te
B. CLOCK TIMES AND TEMPERATURES
c 1. FINAL TAP
TIME TEMP
2. LADLE INOCULANT ADDED
3. CASTINGP OUR BEGAN
c. ELAPSED TIMES
1. HOLD TIME (FINAL TAP TO INOCULANT')
TIME
2. HOLD TIME (INOCULANTO STARTO F bOUR)
3. TIME OF POUR (START TO FULL MOLD)
D. FINAL CHILL( ASTM A367) WEDGE TYPE MEASUREMENT
E. INNOCULANT TYPE AMOUNT
II. ACCEPTANCE CRITERIA
6" X 6" MID RADIUS
1. TENSILE STRENGTH
2. HARDNESS: CibNDER DECK AND PAN RAIL .
CRANKCASE DOORS .
CRANKCASE BEARING BOSS .
ij ;;cRosTRucTuRE (LAB REF. ~0. 1
ST IRON MATRIX (VOLUME X) TGRAPHITE FLAKE SIZE (Cont'd)
FERRITE CONTENT OTHER TYPE
CARBIDEC ONTENT SIZE
b) GRAPHITE FLAKE SIZE
OMINATET YPt
---_
c) INTERCELLULAR CARBIDES (VOLUME %)
(6" X 6" m BAR)
I certify this casting meets the requirements of C50E6g S2 and the specified
pattern number.
Signed:
DATE Title:
Figure 5
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p,=r=,op 1 I29188 WRITTEN 5
BY T.E. Johnsow BY K.t. tiscneM{l PAOL IL ON l AOI r
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铸冶艺人

回复 1# 铸冶艺人
上面复制了部分美国GE公司对大型汽缸体，灰铁250的验收要求，前面对化学成分要求里面，可以看见，除了正常成分之外，还有钛，铅，氮，等等要求，能够看懂英语几个常用铸造词汇的差不多都可以看出来。
以前在论坛上多次谈过关于微量元素对灰铁的影响，还有灰铁屈服强度的要求也在里面有。这个验收标准可以看出，GE要求的严格程度。在标准的后面有要求生产厂家对生产过程的详细记录，特别对铁水中钛，氮等等含量要如实记录。
希望铸造朋友们对微量元素对灰铁强度的影响要特别重视。
由于该文件原来文本格式问题，我的复制不全，也没有图片。

实干家

回复 1# 铸冶艺人

前辈将原件发了，能不能请英语好的帮忙翻译一下，以便大家了解其验收标准，学习学习。谢谢！

铸冶艺人

回复 3# 实干家
我简单翻译一下：化学成分的后面几条是：N，60-120PPM。Pb，60-120PPM，0.005%最大。Ti，0.025%最大。Te，0.020%最大。
不知对不对？这是高档次灰铁的起码要求。

zjy95381

回复 4# 铸冶艺人


    光配光谱也没用啊，氮好像不能做吧

铸冶艺人

回复 5# zjy95381
有氧氮仪可以分析氮和氧，好的有美国力可的，大的钢铁工厂都有配置，特别是做合金钢。
光谱仪增加氮通道，很贵，也测的不准确。
这个帖子的本意是通过这个标准，使大家对灰铁熔炼中，微量元素影响引起注意，特别是重要灰铁铸件更要注意。

czwjn

老外的研究还是很深啊！

铸冶艺人

机床铸件高牌号灰铁

回复 3# 实干家
最近回到10余年前工作的台资铸造企业看朋友，在台湾比较有名气的机床铸造企业，现在规模扩大了，全部呋喃树脂砂铸造，熔炼主要是电炉，5吨的，台湾产电炉，冲天炉继续保留，不经常使用。每月有一千余吨产量，主要发给在大陆生产机床的各个台湾工厂。
在厂里，朋友问到，他们的机床铸件硬度总是不合格，我叫拿来光谱仪成分分析看看，见附件照片，钛含量经常在0.03-0.04多%，里面还加入0.2多%的铜和铬。原因在哪里？根据以往的经验，我看主要是钛含量超标了，他们可能没有意识到。如果钛含量控制在0.025%以下，在他们的硬度一般不会出问题。

小猫钓鱼

很不错 受教了

liuyuzhong

回复 5# zjy95381


    氮能测。

liuyuzhong

回复 8# 铸冶艺人


    Ti 是强烈白口化元素。

铸冶艺人

回复 11# liuyuzhong
钛在

   你说的应该在 炼钢专业里面是有益合金元素。这个帖子的意思是，在做要求质量较高的高牌号灰口铸铁时，把钛作为有害微量元素之一来对待，需要控制其含量。我们国家各地生产的铸造用生铁里面，有害微量元素含量较多，所以提出注意。近几年，铸造行业对各种有害微量元素对灰铁的影响都开始注意了。

铸冶艺人

回复 12# 铸冶艺人
接着前面谈：06年中，负责新潮铸造新厂的电炉熔炼，使用生铁，废钢和回炉料配料，生产灰铁300，浇注日本牧野机床床身，当时老厂冲天炉也在正常生产，定时拿试样来新厂做光谱仪分析。电炉配料成分目标控制按冲天炉成分控制，结果使人不解，电炉的强度和硬度总是比要求的低，而冲天炉熔炼的铁水浇注机床没有问题。年轻时，80年在408厂，我是第一任熔炼工艺员，试炉成功后即转到铸造分厂工作，经历不多，但对电炉熔炼相对来讲，还是比较熟悉。分析原因大家总是认为电炉孕育措施，没有冲天炉好（冲天炉出铁槽很长，孕育效果好），再三改善孕育，效果不好，最后没有办法，只好降低碳硅含量，满足铸件要求。当时生铁是胶东地区的“本溪生铁”，废钢等等质量都很好。
由于老厂冲天炉试样定时拿到新厂光谱仪一起分析，结果都可以看到，所以安排光谱仪把一个月内电炉，冲天炉的分析结果都打印给我，详细查看，并且在现代铸铁杂志上查询有关文章，发现一位姓金的先生写的文章里面谈到，电炉和冲天炉灰铁机械性能的差别，文章也谈到德国企业也有此现象，结果列表在文中，我想德国人使用的生铁，质量也不会很差，总是比国内的生铁要好。最终查明，两者最大的区别在钛的含量不同。冲天炉钛含量都在0.02%以下，而电炉钛都在0.035%以上，常在0.04-0.05%左右。
08年秋天，到普什报到，在会客室看见一位采购商，是美国喀麦隆的代理，他向我提出，普什供应的压缩机缸体，2-3吨重，灰铁300铸件，硬度不足，希望解释，我问了化学成分，他打开电脑给我看了光谱仪分析结果，其中钛含量达到0.057%左右，我说估计是钛的含量太高。介入普什正常工作之后才知道，当时使用了一些四川地方小厂生产的生铁，以后普什逐步淘汰这些生铁的使用，以合成铸铁形式生产灰铁300，基本上再没有出现硬度不足的问题。再以后，干康明斯汽缸体，钛的含量都在0.018-0.025%上下，机械性能各方面都很正常。离开普什之后，徒弟在康明斯汽缸体熔炼岗位上，有个阶段告诉我，汽缸体硬度有问题，我让查钛含量，回答有时钛在0.029-0.03几%，我让他注意，一定要把钛降下来，之后就正常了。
上述现象，几次会议上和相关企业交流，宁夏须崎和北京一机床高壁店工厂都有认同。
氮和钛，作为微量元素含量，对于灰铁的影响，翟启杰老师在他的书中说到，还有很多未知因素，上述我的工作经历只是自己的初步认识，感性或者是实际认识，稍微多说一些就是氮是强化基体，在钢的熔炼中，有高氮钢一说，即氮含量在6000PPM左右含量，在高压下凝固，使钢的强度大大提高，而没有气孔出现。在铸铁中，氮也是这种作用，含量较高，容易出现气孔。如果钛含量高，则消耗强化基体的氮，使灰铁强度，硬度降低。冲天炉熔炼，烧损作用较大，不像电炉熔炼，烧损作用小，保留生铁里面的有害微量元素较多，影响灰铁强度，硬度。认识肤浅一些，主要是工作中经历过，希望大家批评，补充。

混元太极

请教艺人前辈：
“普什供应的压缩机缸体，2-3吨重，灰铁300铸件，硬度不足...其中钛含量达到0.057%左右。”您说的“硬度不足”指的是硬度不够偏软了吧？硬度和抗拉强度有相对应的关系，硬度不够，抗拉能够吗？钛高了断面敏感性即硬度均匀吗？盼赐教！

cc68

不错，有启示。

铸造小猫

学习了，感觉两极分化将会越来越明显，做高端铸件的开始拼设备控制铁水的成分，低端的小作坊继续发扬光大

axinzai001

受教了，谢谢

铸冶艺人

回复 16# 铸造小猫


   
最近看了张文和朋友给我的一本书，是东南大学苏老师写的，书中对氮对灰铁石墨，组织，强度的影响有简单的理论介绍，基本上也印证了我工作中的实际情况，即灰铁中钛，氮对强度的影响。书中关于氮的文字叙述，拍了照片，下载下来，可以很清楚。
一般来讲，在铸造现场做实际技术工作1的人们，可能平常很少去主动看什么技术书籍，出了问题，才会去查找相关资料，查找问题的原因，最终去解释问题的原因，积累自己的经验，才会有目的的去控制问题的发生。不知大家是否认可？

辉精英

从生产实际来看，在五大元素不变的情况下，同样合金加入量，同样孕育，电炉熔炼的灰铁的硬度及强度没有冲天炉的高。估计除了氧元素起到作用外，氮元素也起到重要作用，归根到底，对碳产生了重要作用，影响到石墨的形态和数量，最终对基体和性能产生重要影响。

linwenri

回复 19# 辉精英


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