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EXHIBIT 10b

AMENDMENT NO. 2
TO
CREDIT AGREEMENT

THIS AMENDMENT NO. 2, dated May 4, 2005 (“Amendment No. 2”), to the CREDIT
AGREEMENT, dated as of May 28, 2003, as amended by Amendment No. 1 to the Credit
Agreement (“Amendment No. 1”), dated as of March 28, 2005, is made by and among
ROWAN COMPANIES, INC., a Delaware corporation (the “Shipowner”), GOVCO
INCORPORATED, a Delaware corporation (the “Primary Lender”), CITIBANK, N.A., a
national banking association (the “Alternate Lender”), CITIBANK, N.A., a
national banking association, as facility agent for both the Primary Lender and
the Alternate Lender (and their respective successors and assigns) with respect
to the Floating Rate Note, and its permitted successors and assigns (in such
capacity, the “Facility Agent”), and CITICORP NORTH AMERICA, INC., a Delaware
corporation, as administrative agent for the Primary Lender and the commercial
paper holders of the Primary Lender (and their respective successors and
assigns) (in such capacity, together with its permitted successors and assigns,
the “Administrative Agent,” and together with the Facility Agent, the “Agents”)
(collectively the “Parties”).

WHEREAS, to aid in the construction of the self-elevating mobile offshore
drilling unit to be named “BOB KELLER” (the “Vessel”), on May 28, 2003, the
Parties executed the Credit Agreement, providing for the delivery of no more
than $89,658,000 principal amount of notes designated "United States Government
Guaranteed Ship Financing Obligations, TARZAN II Series";

WHEREAS, the projected Delivery Date of the Vessel, which was April 1, 2005,
was, for a variety of reasons, postponed to September 2005;

WHEREAS, in connection with the postponement of the projected Delivery Date of
the Vessel, the Parties executed Amendment No. 1, which extended the Final
Disbursement Date and the Commitment Termination Date thereunder from April 1,
2005 to December 31, 2005; and

WHEREAS, the Shipowner desires to further amend the Credit Agreement in order to
provide, inter alia, for a change in the Payment Dates and Stated Maturity of
the Floating Rate Note.

NOW THEREFORE, in consideration of the mutual rights and obligations set forth
herein and of other good and valuable consideration,
 

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the receipt and sufficiency of which are hereby acknowledged, the Parties agree
as follows:

ARTICLE I
AMENDMENTS

1. Section 2.04. Section 2.04 of the Credit Agreement is hereby amended to read
as follows:

2.04 Relationship of Floating Rate Note and Fixed Rate Note. Disbursements from
the Credit Facility shall become the indebtedness of the Shipowner to the
Lenders under the Floating Rate Note. The Shipowner shall redeem the Floating
Rate Note in full by causing to be issued one or more Fixed Rate Notes and using
the proceeds thereof to repay the Floating Rate Note in full no later than the
earliest of (i) four years from the Delivery Date, (ii) September 1, 2009, or
(iii) at the request of the Secretary, within fifteen (15) Business Days from
the date upon which the Trigger Event shall occur. At its option, and from time
to time, the Shipowner may redeem all or any portion of the indebtedness under
the Floating Rate Note by causing a Fixed Rate Note or series of Fixed Rate
Notes to be issued at any time during or after the construction of the Vessel,
so long as such redemption of the Floating Rate Note from the proceeds of Fixed
Rate Note(s) does not occur later than the earliest of (i) four years after the
Delivery Date, (ii) September 1, 2009, or (iii) at the request of the Secretary,
within fifteen (15) Business Days from the date upon which the Trigger Event
shall occur, and except for the final redemption, each redemption is in a
minimum amount of $25,000,000; and the Shipowner shall have paid any amount
payable under Section 4.04(a)(iv) or any other provision hereof in connection
therewith.
 
2.  Section 2.05(a). Section 2.05(a) of the Credit Agreement is hereby amended
to read as follows:

2.05 Trigger Event. (a) The Shipowner shall redeem the outstanding indebtedness
under the Floating Rate Note in full by causing to be issued a fixed rate
obligation with a Maturity date of May 10, 2020 whenever the Treasury constant
maturities rate (10-year) as reported by the Federal Reserve Board in
statistical release H.15 (519) (the “Treasury Rate”) equals or exceeds nine
percent (9%) per annum (the “Trigger Event”). If a Trigger Event should occur,
the Shipowner shall redeem the Floating Rate Note in full by causing to be
issued a fixed rate obligation and using the
 
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proceeds thereof to repay the Floating Rate Note in full, at the request of the
Secretary, within fifteen (15) Business Days of receiving notice of the
occurrence of the Trigger Event, pursuant to Section 2.05(d) or of having actual
notice thereof.
 
3.  Section 2.06(b). Section 2.06(b) of the Credit Agreement is hereby amended
to read as follows:
 
(b) In the event that the Alternate Lender does not timely agree to any
requested extension of the Commitment Termination Date in accordance with
Section 2.06(a) (a “Non-Renewal Event”), then the Shipowner may, at its sole
discretion, redeem the outstanding indebtedness under the Floating Rate Note in
full in accordance with Section 2.04 by causing to be issued a fixed rate
obligation with a Maturity date of May 10, 2020. If the Shipowner does not
redeem the Floating Rate Note on or before the Commitment Termination Date
expires, (i) the Primary Lender shall, prior to such date, assign to the
Alternate Lender all of its interest in its outstanding indebtedness under this
Agreement and the Floating Rate Note, and all of its other rights and
obligations hereunder, in exchange for the Alternate Lender’s payment of an
amount equal to the outstanding principal balance of the assigned indebtedness,
plus the amount of all interest and fees accrued through the date of such
assignment; and (ii) the Alternate Lender shall accept and assume all of the
Primary Lender’s rights and obligations under this Agreement and the Floating
Rate Note. From and after the date of the assignment (which shall be evidenced
by an assignment agreement in form and substance acceptable to the Lenders and
the Shipowner), the Primary Lender shall cease to be a Lender hereunder, and
shall have no rights or obligations hereunder or under the Floating Rate Note,
except for any rights which by their express terms survive the termination of
this Agreement or the Floating Rate Note.
 
4.  Section 4.01. Section 4.01 of the Credit Agreement is hereby amended to read
as follows:
 
4.01 Principal Repayment. The Shipowner shall repay the Outstanding Principal of
the Floating Rate Note as follows:

(i)  
in installments in the principal amount of $2,989,000, on each Payment Date
commencing on November 10, 2005, and continuing until May 10, 2009, and

 
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(ii)  
the full amount of the Outstanding Principal evidenced by the Floating Rate
Note, on the earliest of (i) four years from the Delivery Date, (ii) September
1, 2009, or (iii) at the request of the Secretary, within fifteen (15) Business
Days from the date upon which the Trigger Event shall occur.

 
5.  Section 4.05. Section 4.05 of the Credit Agreement is hereby amended to read
as follows:
 
4.05 Evidence of Debt. The Shipowner agrees that to evidence further its
obligation to repay all amounts disbursed under the Credit Facility, with
interest accrued thereon, it shall issue and deliver to the Facility Agent, in
accordance with the written instructions of the Facility Agent, the Floating
Rate Note. The Floating Rate Note shall (i) be in the form of Exhibit A to
Supplement No. 1 to the Indenture; (ii) bear the Secretary's Guarantee, and
(iii) be valid and enforceable as to its principal amount at any time only to
the extent of the aggregate amounts then disbursed and outstanding thereunder,
and, as to interest, only to the extent of the interest accrued thereon at the
rate guaranteed by the Secretary, with any interest in excess thereof being
evidenced by this Agreement.

6. Concerning Exhibit 1. (a) The following definitions in Exhibit 1 to the
Credit Agreement are hereby amended to read as follows:

“Fixed Rate Note” shall mean the Note substantially identical to the Form of
Exhibit B to Supplement No. 1 to the Indenture, appropriately completed.

“Floating Rate Note” shall mean the Note substantially identical to the Form of
Exhibit A to Supplement No. 1 to the Indenture, appropriately completed.
 
“Payment Date” shall mean May 10 and November 10 of each year, beginning on
November 10, 2005.

"Vessel” means the Shipowner's self-elevating mobile offshore drilling unit to
be named the BOB KELLER and constructed by LETOURNEAU, INC. in accordance with
the Construction Contract, including all work and material heretofore or
hereafter performed upon or installed in or placed on board such Vessel,
together with related appurtenances, additions, improvements, and replacements.

(b) Exhibit 1 to the Credit Agreement is further amended by adding the following
definitions to read as follows:
 
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“Amendment No. 2 to the Credit Agreement” means the Amendment No. 2 to the
Credit Agreement dated May 4, 2005, among the Shipowner, the Lenders and Agents.

“Supplement No. 1 to the Indenture” shall mean the Supplement No. 1 to the Trust
Indenture dated May 4, 2005, between the Shipowner and the Indenture Trustee.

ARTICLE II
MISCELLANEOUS

1. All other capitalized terms used herein have the meanings set forth in
Exhibit 1 to the Credit Agreement.
 

 
2. Except as so amended, the provisions of the Credit Agreement, as amended by
Amendment No. 1, are hereby confirmed, and shall remain in full force and
effect.
 

3. This Amendment No. 2 to the Credit Agreement may be executed in several
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

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IN WITNESS WHEREOF, this Amendment No. 2 to the Credit Agreement has been duly
executed by the Parties as of the day and year first above written.

ROWAN COMPANIES, INC., as  
the Shipowner
 
GOVCO INCORPORATED, as the Primary Lender, by Citicorp North America, Inc., its
attorney-in-fact.
     
By:____________________________
 
By: _______________________________
(Signature)
 
(Signature)
     
Name: William H. Wells
 
Name: P. A. Botticelli
(Print)
 
(Print)
     
Title: Vice President - Finance and Treasurer
 
Title: Vice President
(Print)
 
(Print)
     

CITIBANK, N.A., as Facility Agent
 
CITIBANK, N.A., as the Alternate Lender
     
By: ______________________________
 
By: _______________________________
(Signature)
 
(Signature)
     
Name: Ae Kyong Chung
 
Name: Ae Kyong Chung
(Print)
 
(Print)
     
Title: Vice President
 
Title: Vice President
(Print)
 
(Print)

   
CITICORP NORTH AMERICA, INC., as the Administrative Agent
         
By: _______________________________
   
(Signature)
         
Name: P. A. Botticelli
   
(Print)
         
Title: Vice President
   
(Print)

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CONSENT:

Pursuant to the Section 11.08 of the Credit Agreement, the Secretary hereby
consents to this Amendment No. 2 to the Credit Agreement and confirms the
continued Guarantee of the Obligation of the United States of America pursuant
to Title XI of the Merchant Marine Act, 1936, as amended.

(SEAL)
 
Attest:
   
UNITED STATES OF AMERICA,
SECRETARY OF TRANSPORTATION
MARITIME ADMINISTRATION
                                 
By:
 
Assistant Secretary
   
Secretary

 
 
 
 
 
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