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                           Filed by National-Oilwell, Inc.
                           Pursuant to Rule 425 under the Securities Act of 1933
                           Commission File No.: 1-12317
                           Subject Company:  IRI International Corporation


THE FOLLOWING IS A PRESS RELEASE DISSEMINATED BY NATIONAL-OILWELL, 
INC. ON MARCH 16, 2000:



JOINT RELEASE


NEWS                                                  CONTACT:  NATIONAL OILWELL
                                                                   STEVE KRABLIN
                                                                  (713) 346-7773


                                                               IRI INTERNATIONAL
                                                              ROBERT L. HARGRAVE
                                                                  (713) 868-8847

FOR IMMEDIATE RELEASE


             NATIONAL OILWELL AND IRI ANNOUNCE SIGNING OF DEFINITIVE
                                MERGER AGREEMENT


HOUSTON, TX, March 16, 2000--National-Oilwell, Inc. (NYSE: NOI) and IRI
International Corporation (NYSE: IIR) jointly announced today the signing of a
definitive merger agreement.

The merger agreement, unanimously approved by each company's board of directors,
calls for IRI stockholders to receive .3385 share of National Oilwell common
stock for each IRI common share. Based on National Oilwell's closing price
yesterday, the transaction is currently valued at $8.04 per IRI share, or a
total of approximately $320 million. A total of approximately 13.5 million
shares of National Oilwell common stock will be issued in the transaction which
will be accounted for as a pooling of interests and is expected to be tax-free
to both companies and IRI stockholders. At December 31, 1999, IRI had no debt
and cash balances and marketable securities valued at approximately $50 million.
The combination is expected to be accretive to 2000 and 2001 earnings per share
of National Oilwell, excluding one-time charges related to expenses associated
with the transaction.

Joel V. Staff, Chairman, President and CEO of National Oilwell, said "The merger
of National Oilwell and IRI provides a strategic and complementary fit with our
existing businesses. National Oilwell's drilling equipment business has largely
focused in the deep land and offshore markets, while IRI has concentrated on
mobile well servicing and 


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drilling rigs. We expect to achieve significant combination benefits as we
integrate the best manufacturing, sales and service operations of the combined
companies. We are particularly excited about the growth opportunities for
National Oilwell's downhole products business as we combine with IRI's Bowen
product line."

Hushang Ansary, Chairman and Chief Executive Officer of IRI, said "This
transaction provides a tremendous opportunity for IRI's stockholders and
employees. Along with National Oilwell's recent combination with Hitec, the
combined company will have the ability to offer leading edge technology and
automation in a full complement of "best-in-class" products to the global
markets. " Mr. Ansary has been invited to join the Board of Directors of
National Oilwell.

The transaction is subject to approval of both National Oilwell and IRI
stockholders as well as customary regulatory approvals. Holders of the majority
of IRI's outstanding shares as well as National Oilwell's largest stockholder
and its CEO have entered into voting agreements in support of the transaction.
It is anticipated that stockholders meetings and the closing of the transaction
would occur during the second quarter of this year. Merrill Lynch & Co. acted as
financial advisor to National Oilwell and Lehman Brothers acted as financial
advisor to IRI.

National Oilwell is a worldwide leader in the design, manufacture and sale of
comprehensive systems and components used in oil and gas drilling and
production, as well as in providing supply chain integration services to the
upstream oil and gas industry.

IRI is a world leader in the design, engineering, manufacture, sales and rental
of oilfield equipment and downhole tools.

This press release and any oral statements made in connection therewith contain
forward-looking statements within the meaning of Section 21E of the Securities
Exchange Act of 1934 concerning, among other things, National Oilwell's and
IRI's prospects and development for their combined operations and the
integration of business and operations of National Oilwell and IRI, as well as
recent acquisitions by National Oilwell, all of which are subject to certain
risks, uncertainties and assumptions. These risks and uncertainties include the
ability of National Oilwell and IRI to achieve the cost savings and revenue
benefits currently expected from the proposed merger and the timing and receipt
of approvals for the merger. Other risks and uncertainties, which are more fully
described in documents filed by National Oilwell and by IRI, including each
company's Annual Report on Form 10-K, could cause actual results to differ from
those contained in the forward-looking statements.

The foregoing may be deemed to be offering materials of National-Oilwell, Inc.
in connection with National Oilwell's proposed acquisition of IRI International
Corporation on the terms and subject to the conditions in the Agreement of
Merger, dated as of March 15, 2000, among National Oilwell, IRI and Arrow
Acquisition Corp.

STOCKHOLDERS OF NATIONAL OILWELL AND IRI AND OTHER INVESTORS ARE URGED TO READ
THE JOINT PROXY STATEMENT/PROSPECTUS THAT WILL BE INCLUDED IN THE REGISTRATION
STATEMENT ON FORM S-4 WHICH NATIONAL OILWELL WILL FILE WITH THE SEC IN
CONNECTION WITH THE PROPOSED MERGER BECAUSE IT WILL CONTAIN IMPORTANT
INFORMATION ABOUT NATIONAL OILWELL, IRI, THE MERGER, THE PERSONS SOLICITING
PROXIES IN THE MERGER AND THEIR INTERESTS IN THE MERGER AND RELATED MATTERS.
After it is filed with the SEC, the joint proxy 


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statement/prospectus will be available for free, both on the SEC's web site
(http://www.sec.gov) and from National Oilwell by directing a written or oral
request for copies to Gay Mather, Director of Communications, National-Oilwell,
Inc., 10000 Richmond Ave., Houston, Texas 77042, telephone: (713) 346-7775.

In addition to the proposed registration statement and joint proxy
statement/prospectus, National Oilwell and IRI file annual, quarterly and
special reports, proxy statements and other information with the SEC. You may
read and copy any reports, statements or other information filed by either
company at the SEC's public reference rooms at 450 Fifth Street, N.W.,
Washington, D.C. 20549 or at the SEC's other public reference rooms in New York,
New York and Chicago, Illinois. Please call the SEC at 1-800-SEC-0330 for
further information on the public reference rooms. National Oilwell's and IRI's
filings with the SEC are also available to the public from commercial
document-retrieval services and on the SEC's web site at http://www.sec.gov.



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