HQ 951154
JUNE 26 1992
CLA-2:CO:R:C:M 951154 JAS
Ms. Sue S. Wilkerson
Cummins Engine Company, Inc.
Box 3005
Columbus, IN 47202-3005
RE: Cylinder Block Casting; Diesel Engine Block; Engine
Block Casting; Rough Gray Iron Casting; Parts of
Internal Combustion Diesel Engines; Subheading
8409.99.10; Advancement Beyond Cleaning; Stress
Relieving; Other Parts; Subheading 8409.99.99
Dear Ms. Wilkerson:
In your letter of February 7, 1992, you inquire as to the
tariff status of certain cylinder block castings from Brazil.
Blueprints and drawings were submitted. Our ruling follows.
FACTS:
The articles in issue are described as rough, gray iron
cylinder block castings for use in the manufacture of diesel
engines. Metal foundries produce these castings as follows: pig
iron, steel and other metals in small amounts, in the form of
scrap, machining swarf, pit cast, and in-house reserves, are
reduced to molten gray iron in coke fired cupolas and electric
furnaces. This molten metal is poured into mold cavities and
allowed to harden. The castings are then removed by a shakeout
machine. These castings conform to a material specification
outlining chemical composition, mechanical properties,
microstructure, etc. It is apparent that iron predominates by
weight over any other base metal constituent.
You state that internal stresses are reduced when castings
are left to cool very slowly in the mold so that the thick and
thin sections cool at approximately the same rate. However, to
maximize mold utilization and overall production capacity some
companies remove their castings from the mold prematurely and
allow them to air cool. This causes residual stresses to
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develop which makes the castings unacceptable for use in diesel
engines. To relieve these stresses, the castings are placed in a
furnace at 400-650 degrees F. The temperature is gradually
increased to 1000-1150 degrees F and the castings held at this
temperature for one hour per inch of thickness based on the
heaviest section of the casting. They are then control cooled
back to the original temperature at a rate not to exceed 250
degrees F per hour. After this heat treatment the castings are
surface finished by some combination of chipping, grinding and
sand blasting.
You state that these cylinder block castings are currently
classified under the provision for other parts suitable for use
solely or principally with the engines of heading 8407 or 8408,
in subheading 8409.99.99, Harmonized Tariff Schedule of the
United States (HTSUS). You maintain they should be classified in
subheading 8409.99.10, a duty-free provision for other cast-iron
parts not advanced beyond cleaning, and machined only for the
removal of fins, gates, sprues, and risers.
ISSUE:
Whether stress relieving is an advancement beyond cleaning
for purposes of subheading 8409.99.10.
LAW AND ANALYSIS:
Merchandise is classifiable under the Harmonized Tariff
Schedule of the United States (HTSUS) in accordance with the
General Rules of Interpretation (GRIs). GRI 1 states in part
that for legal purposes, classification shall be determined
according to the terms of the headings and any relative section
or chapter notes, and provided the headings or notes do not
require otherwise, according to GRIs 2 through 6. GRI 6 states
in part that for legal purposes, the classification of goods in
the subheadings of a heading shall be determined according to the
terms of those subheadings and any related subheading notes and,
by appropriate substitution of terms, to GRIs 1 through 5, on the
understanding that only subheadings at the same level are
comparable. For the purposes of Rule 6, the relative section,
chapter and subchapter notes also apply, unless the context
requires otherwise.
Initially, the Explanatory Notes (ENs) constitute the
Customs Cooperation Council's official interpretation of the
Harmonized System and are useful in ascertaining the
classification of merchandise under the System. Relevant ENs at
p. 1152 indicate that, with certain exceptions not relevant here,
heading 8409 covers parts of internal combustion piston engines
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of heading 8407 or 8408 (e.g., pistons, cylinders and cylinder
blocks, cylinder heads, cylinder liners, etc.). Therefore, the
cylinder block castings are considered to be parts of heading
8409.
In the as-cast state, most castings are relatively brittle
and possess poor mechanical properties. To render them
serviceable they must be subjected to a variety of heat
treatments designed to refine the grain, relieve internal
stresses and develop the desired physical and mechanical
properties. One such heat treatment is stress relieving. Unlike
other heat treatments such as annealing and quenching and
tempering, which you argue are clearly advancements in the as-
cast articles, stress relieving temperatures are not high enough
to alter the microstructure or mechanical properties of the
castings. You state the process merely "re-creates" the normal
aging process that would occur had the castings been allowed to
cool in the mold.
The term stress relieving is defined in the Babcock and
Wilcox text Guide to Steel Tubing Terminology as "a heat
treatment which reduces the internal stresses that have been
induced by casting, quenching, welding, cold working, etc." The
USX (formerly United States Steel) publication The Making,
Shaping and Treating of Steel, 10th. Ed., and similar
publications are in accord. Noting this definition, in
conjunction with the casting process you have described, we
conclude that stress relieving is not a required step in the
production of all merchantable gray cast iron castings, but only
those that have been prematurely removed from the mold. From the
record it appears that stress relieving is not commercially
regarded as an integral part of the casting process. It is a
process performed subsequently to improve the quality of a
casting.
The classification of the instant cylinder block castings in
one of the remaining applicable subheadings of heading 8409
depends on the principal use in the United States of the class or
kind to which they belong. See Additional U.S. Rule of
Interpretation 1(a), HTSUS. In a related ruling (HQ 951990,
dated June 17, 1992), to your company, we held that based on the
available evidence of principal use, certain diesel engine
cylinder heads were classifiable in subheading 8409.99.91, HTSUS,
a provision for parts suitable for use solely or principally with
the engines for vehicles of subheading 8701.20, or heading 8702,
8703 or 8704.
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HOLDING:
Under the authority of GRI 1, applied at the subheading
level through GRI 6, gray iron cylinder block castings that have
been stress relieved are considered advanced beyond cleaning for
purposes of subheading 8409.99.10, HTSUS.
The instant castings are classifiable in subheading
8409.99.91, HTSUS, a provision for other parts suitable for use
solely or principally with the engines of heading 8407 or 8408.
The column 1 rate of duty is 3.7 percent ad valorem. Articles
from Brazil classifiable in this provision are eligible for free
entry under the Generalized System of Preferences (GSP), upon
compliance with the law and any applicable regulations.
This classification is based on the best evidence available
to us at this time. Additional evidence of principal use that
comes to our attention may cause us to reconsider our position.
Sincerely,
John Durant, Director
Commercial Rulings Division