Page 40 - Fuels & Lubes International 2013 - Q1

丰田和福特赞助开发。两者均是直接或
通过日本汽车制造商协会（JAMA）的
ILSAC成员。第一项测试用于评价氧化
稳定性和活塞积炭，第二项测试用于
评价阀组磨损。程序VH监测油泥和积
炭。VIE有可能是用于替代目前的VID
燃油经济性测试的名称。
无论其如何命名，最后一项测试尤
其重要。燃料经济性是世界上许多国家
法定的要求，一辆车在其生命周期中的
燃料经济性对于当今消费者在面对高
油价时是一个重要考虑因素。因此，通
常会有一定的润滑性能要求。
“我们的配方一般是为了能够通
过这些测试，” 德国公司在美国的下
属机构Evonik油品添加剂OEM业联络
经理Don Smolenski说，“我们一直认
为，他们是标准中最具相关性的部分，
因为这项测试是在路上行使的真实量
产发动机上进的。”
新测试是十分必要的，因为进
行旧测试的硬件将很快停止供货。例
如，GF-5中对凸轮轴负荷磨损的监测
程序IVA所使用的是1994年发动机。
这需要在现代的硬件上进行的测试来
替代。
GF-6将在两个子类中推广，6A和
6B。前者限用于SAE20及以上的粘度
等级中，使之适用于路上的发动机，
并具有向后的兼容性。第二个子类用
于开发新发动机，因为它提供了一个
更低的粘度等级，SAE16，其150o C下
高温高剪切粘度最低为2.3 cP，100°C
下动态粘度为 6.1-8.1 cSt。（参考数
据：SAE20的对应值分别为2.6 cP 和
5.6-9.3 cSt）
以更低的粘度提升燃料经济性是
开发GF-6的主要动力。然而，这种方法
可能存在极限，美国加州Richmond的
Chevron Oronite 全球AEO开发工程
师Trevor Miller说。
去年九月在瑞典Malmo，在汽
车工程师协会（S A E）之前的发言
中，Miller报告了一项采用高温高剪切
粘度分别为2.9、2.6、2.3和1.8 cP系列
的油品所进行的研究。燃料经济性随
粘度下降至2.3 cP而提高，但从2.3
降到1.8 cP时，燃料经济性实际上是
下降的。
“进一步降低粘度并不一定会给
你带来燃料经济性的提升，” Miller
说。“这有可能，但取决于发动机。”
更低的粘度也可能对部件磨损带
来不利影响。Chevron Oronite
发现，监测程序IVA凸轮轴测试中的
铁含量是判断磨损的一个很好的
指示。在后期，浓度上升很快，表
明磨损加剧。出现快速上升的点
看来是随着粘度的下降出现得越
gF-6 is actually being rolled
out as two subcategories, 6A and
6b. The first is limited to viscosity
grades of SAe 20 and above,
making it suitable for engines
on the road today and therefore
more backward compatible. The
second subcategory permits the
development of new engines
because it offers a new, lower
viscosity grade, SAe 16, which
has a high-temperature high-
shear viscosity minimum of
2.3 centipoise (cp) at 150oC and
kinematic viscosity limits of 6.1-
8.1 centistokes (cSt) at 100°C. For
reference, the corresponding values
for SAe 20 are 2.6 cp and 5.6-9.3
cSt, respectively.
The drive toward lower
viscosity for boosting fuel
efficiency has been a powerful
impetus for the development of
gF-6. however, there could be a
limit to the effectiveness of this
approach, said trevor Miller, global
AeO development engineer with
Chevron Oronite in richmond,
Calif., u.S.A.
In a presentation before the
Society of Automotive engineers
(SAe), in Malmo, Sweden, last
September, Miller reported on a
study using a matrix of oils where
high-temperature, high-shear
viscosity was 2.9, 2.6, 2.3 and 1.8 cp.
Fuel economy increased as viscosity
dropped to 2.3 cp. however, in
moving from 2.3 to 1.8 cp, fuel
economy actually decreased.
“Moving down in viscosity
doesn’t necessarily give you an
increase in fuel economy,” said
Miller. “It can. It just depends on
the engine.”
Lower viscosity might also
negatively affect component wear.
Chevron Oronite has found that
looking at iron concentration
during the Sequence IVA camshaft
test is a good predictor of wear
results. during the early phases
of testing, they found that the rate
of increase in iron concentration
was linear. At later stages, the
rate increased rapidly, signifying
increased wear. The point at which
this occurred seemed to happen
earlier and earlier as viscosity
decreased.
New vehicle operating regimes
could prove to be a complicating
factor in the assessment of these
issues. For instance, the start-stop
operation of hybrid vehicles might
worsen the situation, something
that was considered when the needs
statement for gF-6 was drafted.
There has been little activity on
this test development front to date.
however, it is possible that a test to
address this will be created before
gF-6 arrives, said Miller.
gF-6 oils will be better than
gF-5 oils across the board. For
instance, the proposed specification
calls for average engine and rocker
sludge performance to be 9 versus
8.3 for gF-5, and average piston
cover varnish to be 8 versus 7.5
for gF-5, said dennis bachelder,
a senior engineer with ApI who
also spoke at the petroChina
conference. Changes like these will
further enhance seal compatibility,
wear protection and compatibility
with ethanol-blended fuels.
Oils that meet ApI’s resource
conserving SN category are
equivalent to gF-5. ApI takes steps
to verify that lubricants as sold are
worthy of carrying its trademarked
donut designation.
The ApI has an aftermarket
audit program that “is intended
to ensure those oils meet ApI
standards,” bachelder said. It is
likely that ApI will continue this
effort with gF-6. however, ApI
will not be running engine tests;
instead, it will rely on bench tests
and compare test results to a
database compiled when oils go
through certification.
As for the future beyond gF-
6, there are ongoing talks about
how to merge the various engine
oil standards. bachelder said such
efforts might not yield much in the
way of results, given that vehicle
makers often want to retain control
of the standards their cars and
trucks must meet. OeMs set what
tests must be run and what results
constitute passing. That approach
doesn’t work for standards
developed in the open by a
consensus of various stakeholders,
something ApI favors.
来越早。
新车辆的运行范围可能在评估
这些因素时成为一个复杂的因素。例
如，混合动力汽车的开停操作可能加
剧这种情况，这在起草GF-6时需要加
以说明。到目前为止，在这项测试的
开发中所做甚少。然而，有可能用于
评价这个问题的测试在GF-6之前就
会出现，Miller说。
GF-6油在各方面将优于GF-5。
例如，所建议的规格要求平均发动机
和油泥性能为9，而GF-5中，此值为
8.3；平均活塞漆膜为8，而GF-5中为
7.5，同在中石油大会上发言的来自
API的Dennis Bachelder说。类似于
这样的变化将进一步提升采用调合了
乙醇的燃料时的密封兼容性和对磨损
的保护和兼容性。
符合API资源保护的SN类油品
相当于GF-5。API自己验证在售的润
滑油是否符合带有此环形注册商标的
要求。
API有一项售后市场审计项目，
“旨在确保那些油品符合A P I 标
准，”Bachelder说。在GF-6推出
后，AP I 有可能继续这个项目。然
而，API将不再进行发动机测试；相反，
它将依赖于台架测试并将测试结果与
数据库中油品进行认证时所提交的数
据进行对比。
在GF-6之后，还有更多的有关如
何将不同的发动机油标准进行统一的
讨论。Bachelder说，由于汽车制造
商通常希望保持对其自己所生产的汽
车和卡车的标准的控制，这项工作就
结果而言可能没有太大的进展。OEM
决定应该进行什么测试，什么样的结
果表示通过。那种方法通常并不适合
API所希望的在开放的环境中各利益
相关方达成一致的标准制定方式。
>> “ILSAC GF-6” cont. from page 8 >> “ILSAC GF-6”上接第8页
FUELS & LUBES INTERNATIONAL Quarter One 2013 40