<PAGE>
                                                                    EXHIBIT 10.1

                                 AMENDMENT NO. 1
                               TO CREDIT AGREEMENT

         THIS AMENDMENT NO. 1 TO CREDIT AGREEMENT, dated as of September 27,
2002 (the "Agreement") relating to the Credit Agreement referenced below, is by
and among WOLVERINE TUBE, INC., a Delaware corporation (the "Company"), its U.S.
and Canadian Subsidiaries identified as Subsidiary Borrowers on the signature
pages hereto and any additional U.S. or Canadian Subsidiaries of the Company
which become parties to the Credit Agreement in accordance with the terms
thereof (collectively referred to as the "Subsidiary Borrowers" and individually
referred to as a "Subsidiary Borrower") (hereinafter, the Company and the
Subsidiary Borrowers are collectively referred to as the "Borrowers" or referred
to individually as a "Borrower"), each of the financial institutions identified
as Lenders on the signature pages hereto (the "Lenders" and each individually, a
"Lender"), WACHOVIA BANK, NATIONAL ASSOCIATION, ("Wachovia"), acting in the
manner and to the extent described in Article XIII of the Credit Agreement (in
such capacity, the "Administrative Agent") and CONGRESS FINANCIAL CORPORATION
(CANADA) acting in the manner and to the extent described in Article XIII of the
Credit Agreement (in such capacity, the "Canadian Agent"). Terms used but not
otherwise defined herein shall have the meanings provided in the Credit
Agreement and the provisions of Sections 1.2, 1.3 and 1.4 of the Credit
Agreement related to the definitions shall apply herein.

                                   WITNESSETH

         WHEREAS, a $37,500,000 credit facility has been extended to the
Borrowers pursuant to the terms of that certain Credit Agreement dated as of
March 27, 2002 (as amended, modified or otherwise supplemented from time to
time, the "Credit Agreement") among the Borrowers, the Lenders, the
Administrative Agent and the Canadian Agent;

         WHEREAS, the Borrowers have requested that certain Lenders provide an
Interest Rate Protection Agreement regarding certain obligations pursuant to the
2008 Senior Note Indenture or the 2009 Senior Note Indenture and to induce such
Lenders to provide such Interest Rate Protection Agreement, the Borrowers have
agreed to add, to the extent not already included, Interest Rate Protection
Agreements as Secured Obligations pursuant to the U.S. Security Agreement and as
Pledgor Obligations pursuant to the U.S. Pledge Agreement; and

         WHEREAS, as a result of the inducement described herein and the other
good and valuable consideration provided to the Lenders entering into Interest
Rate Protection Agreements with certain of the Borrowers, the undersigned
Lenders agree to enter into certain Interest Rate Protection Agreements and to
the amendments to certain of the Credit Documents set forth in this Agreement;

         NOW, THEREFORE, in consideration of these premises and other good and
valuable consideration, the receipt and sufficiency of which are hereby
acknowledged, the parties hereto agree as follows:

<PAGE>

         (A)      Amendments.

         1.       The definition of "Hedging Agreements" in Section 1.1 of the
Credit Agreement is amended by adding the following to the end of the definition
"or any other derivative product hedging arrangement."

         2.       The definition of "Obligations" in Section 1.1 of the Credit
Agreement is amended by replacing "all liabilities and obligations owing from
any Borrower to any Lender, or any affiliate of a Lender, arising under Interest
Rate Protection Agreements entered into for the purpose of hedging interest rate
risk under this Credit Agreement and the other Credit Documents," with "all
liabilities and obligations arising under Interest Rate Protection Agreements,".

         3.       The definition of "U.S. Borrowing Base" in Section 1.1 of the
Credit Agreement is hereby replaced by the following:

                  "U.S. Borrowing Base" means a U.S. dollar amount equal to the
         sum of (a) an amount equal to 85% of Eligible Accounts Receivable of
         the U.S. Credit Parties, plus (b) an amount equal to the lesser of (i)
         60% of Eligible Inventory of the U.S. Credit Parties consisting of raw
         materials and finished goods inventory or (ii) $17,500,000 minus, in
         the Administrative Agent's sole discretion, (c) IRPA Obligations.

         4.       The following definition of "IRPA Obligations" is hereby added
to Section 1.1 of the Credit Agreement in the appropriate alphabetical order:

         "IRPA Obligations" means, a continuing reserve, calculated at a
         frequency determined by the Administrative Agent in its sole
         discretion, for the aggregate amount for liabilities and obligations
         arising under Interest Rate Protection Agreements, each valued as the
         termination value thereof calculated according to a method approved by
         the International Swap and Derivatives Association and as such
         International Swap and Derivatives Association method may be further
         specified in each Interest Rate Protection Agreement.

         5.       The Credit Agreement is amended by replacing the first
paragraph Section 2.1(a) thereof with the following:

         (a)      U.S. Revolving Loan Commitment. Subject to the terms and
         conditions set forth herein, each U.S. Lender agrees, severally and not
         jointly, at any time and from time to time from the Effective Date to
         the U.S Maturity Date, to make revolving loans (each a "U.S. Revolving
         Loan" and collectively, the "U.S. Revolving Loans") in U.S. dollars to
         the U.S. Borrowers; provided, however, that (i) the aggregate amount of
         U.S. Revolving Loans outstanding plus IRPA Obligations plus U.S. LOC
         Obligations outstanding at any one time may not exceed the lesser of
         the U.S. Borrowing Base and the U.S. Revolving Loan Commitment; (ii)
         the aggregate amount of U.S. Revolving Loans outstanding plus Canadian
         Revolving Loans outstanding plus IRPA Obligations plus LOC Obligations
         outstanding plus the aggregate Face Amount of Bankers' Acceptances at
         any one time may not exceed the lesser of the Total Borrowing Base and
         $37,500,000 (U.S.); and (iii) with regard to each


                                       2

<PAGE>

         individual U.S. Lender, the U.S. Lender's pro rata share of outstanding
         U.S. Revolving Loans plus IRPA Obligations plus U.S. LOC Obligations
         outstanding shall not exceed such U.S. Lender's U.S. Revolving Loan
         Commitment Percentage of the U.S. Revolving Loan Commitment; provided,
         however, upon any Canadian Maturity Date occurring prior to the U.S.
         Maturity Date, the Borrowers shall be entitled to receive (and the
         Administrative Agent is hereby authorized by the Lenders to provide) a
         U.S. Revolving Loan in an amount which is sufficient to pay in full the
         Canadian Obligations so long as (i) the proceeds of such U.S. Revolving
         Loan are applied to repay in full the Canadian Obligations
         simultaneously with the making of such U.S. Revolving Loan and (ii) the
         Borrowers are in compliance with the foregoing provisions of this
         Section 2.1(a) immediately after such application and (iii) the
         Borrowers are in compliance in all respects with Section 5.2.

         6.       Section 5.2 of the Credit Agreement is amended by deleting the
word "and" at the end of subsection (g); replacing the period at the end of
subsection (h) thereof with "; and"; inserting the following as immediately
after the end of subsection (h): "(i) Interest Rate Protection Agreements.
Immediately after giving effect to the making of a Loan or the issuance of a
Letter of Credit or the creation of a Banker's Acceptance, the Company shall not
be in violation of the terms of any Interest Rate Protection Agreement." and by
replacing "(b), (c), (d), (e), (f), (g) and (h)" in the last paragraph Section
5.2 with the following "(b), (c), (d), (e), (f), (g), (h) and (i)".

         7.       The text of Section 9.4 of the Credit Agreement is hereby
amended and restated in its entirety to read as follows:

         No Consolidated Party shall dissolve, liquidate or wind up its affairs
         or enter into any transaction of merger, amalgamation or consolidation;
         provided, however, that (i) the Company may merge or consolidate with
         any Subsidiary so long as the Company shall be the continuing or
         surviving corporation, (ii) any U.S. Credit Party (other than the
         Company) may merge or consolidate with any other U.S. Credit Party,
         (iii) any Canadian Credit Party may merge or consolidate with any other
         Canadian Credit Party, (iv) any Subsidiary of the Company that is not a
         Credit Party may be merged with or into any other Subsidiary of the
         Company that is not a Credit Party and (v) any Subsidiary of the
         Company that is not a Credit Party may merge or consolidate with any
         Credit Party so long as the Credit Party shall be the continuing or
         surviving corporation.

         8.       Section 11.1(g) of the Credit Agreement is amended by
replacing the phrase "or the 2008 Senior Notes or the 2009 Senior Notes," with
", the 2008 Senior Notes, the 2009 Senior Notes or any Interest Rate Protection
Agreement".

         (B)      Representations and Warranties. Each Credit Party hereby
represents and warrants that (i) the representations and warranties contained in
Article VI of the Credit Agreement are true and correct in all material respects
on and as of the date hereof as though made on and as of such date (except for
those representations and warranties which by their terms relate solely to an
earlier date) and after giving effect to the transactions contemplated herein,
(ii) no Default or Event of Default exists under the Credit Agreement on and as
of the date hereof and after giving effect to the transactions contemplated
herein, (iii) it has the corporate, limited liability company or limited
partnership power and authority to execute


                                       3

<PAGE>

and deliver this Agreement and to perform its obligations hereunder and has
taken all necessary organizational action to authorize the execution, delivery
and performance by it of this Agreement; (iv) it has duly executed and delivered
this Agreement, and this Agreement constitutes its legal, valid and binding
obligation enforceable in accordance with its terms except as the enforceability
thereof may be limited by bankruptcy, insolvency or other similar laws affecting
the rights of creditors generally or by general principles of equity and (v)
neither the execution and delivery of this Agreement, nor the consummation of
the transactions contemplated therein, nor performance of and compliance with
the terms and provisions thereof will violate or conflict in any material
respect with any material provision of its articles or certificate of
incorporation or certificate of limited partnership or certificate of formation,
bylaws, agreement of limited partnership or limited liability company agreement
or violate, contravene or conflict in any material respect with contractual
provisions of, or cause an event of default under, any indenture, including
without limitation the 2008 Senior Note Indenture and 2009 Senior Note
Indenture, loan agreement, mortgage, deed of trust, contract or other agreement
or instrument to which it is a party or by which it may be bound.

         (C)      Effectiveness. This Agreement shall become effective upon
satisfaction of the following conditions precedent:

                  1.       Executed Agreement. The Administrative Agent shall
         have received a fully executed counterpart of this Agreement.

                  2.       Secretary's Certificates. Receipt by the
         Administrative Agent of secretary's certificates from each Borrower
         (except the Canadian Borrowers party to the Credit Agreement prior to
         the date hereof) dated as of the date hereof either substantially in
         the form required by Section 5.1(d) of the Credit Agreement, mutatis
         mutandis or a bring-down certificate if no change has occurred to the
         secretary's certificate since the delivery thereof on the Closing Date,
         in each case, and otherwise in form and substance acceptable to the
         Administrative Agent.

         (D)      No Other Modification. Except to the extent specifically
provided to the contrary in this Agreement, all terms and conditions of the
Credit Agreement (including Exhibits and Schedules thereto) and the other Credit
Documents shall remain in full force and effect, without modification or
limitation. This Agreement shall not operate as a consent to any other action or
inaction by the Borrowers or any other Credit Party, or as a waiver or amendment
of any right, power, or remedy of any Lender, the Administrative Agent or the
Canadian Agent under the Credit Agreement or any other Credit Document nor
constitute a consent to any such action or inaction, or a waiver or amendment of
any provision contained in the Credit Agreement or any other Credit Document
except as specifically provided herein.

         (E)      Release. In consideration of entering into this Agreement,
each Credit Party (a) represents and warrants to each Agent and each Lender that
as of the date hereof there are no causes of action, claims, actions,
proceedings, judgments, suits, demands, damages or offsets against or defenses
or counterclaims to its Obligations or Secured Obligations under the Credit
Documents and furthermore, such Credit Party waives any and all such causes of
action, claims, actions, proceedings, judgments, suits, demands, damages,
offsets, defenses or counterclaims


                                       4

<PAGE>

whether known or unknown, arising prior to the date of this Agreement and (b)
releases each Agent and each Lender and each of their respective Affiliates,
Subsidiaries, officers, employees, representatives, agents, counsel and
directors from any and all actions, causes of action, claims, actions,
proceedings, judgments, suits, demands, damages and liabilities of whatever kind
or nature, in law or in equity, now known or unknown, suspected or unsuspected
to the extent that any of the foregoing arises from any action or failure to act
with respect to any Credit Document, on or prior to the date hereof.

         (F)      Governing Law. This Agreement shall be governed by and
construed and interpreted in accordance with the laws of the State of North
Carolina, without regard to the principles governing conflicts of laws thereof.

         (G)      INCORPORATION BY REFERENCE OF CERTAIN PROVISIONS. THE
PROVISIONS IN SECTIONS 14.5, 14.6, 14.8, 14.9, 14.10, 14.12, 14.13, 14.14, 14.15
AND 14.19 OF THE CREDIT AGREEMENT ARE HEREBY INCORPORATED BY REFERENCE HEREIN,
MUTATIS MUTANDIS.

                  [Remainder of Page Intentionally Left Blank]


                                       5

<PAGE>

         Each of the parties hereto has caused a counterpart of this Agreement
to be duly executed and delivered as of the date first above written.



                                       COMPANY:

                                       WOLVERINE TUBE, INC.



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       U.S. SUBSIDIARY BORROWERS:

                                       TF INVESTOR, INC.



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       TUBE FORMING HOLDINGS, INC.



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       TUBE FORMING, L.P.

                                       By: Tube Forming Holdings, Inc.,
                                           its General Partner



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------

<PAGE>

                                       WOLVERINE FINANCE COMPANY



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       STPC HOLDING, INC.



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------

<PAGE>

                                       SMALL TUBE MANUFACTURING CORPORATION



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       WOLVERINE JOINING TECHNOLOGIES, INC.



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       WOLVERINE CHINA INVESTMENTS, LLC

                                       By: Wolverine Tube, Inc.,
                                           its Managing Manager



                                           By:
                                              ----------------------------------
                                           Name:
                                                --------------------------------
                                           Title:
                                                 -------------------------------

<PAGE>

                                       CANADIAN BORROWERS:

                                       1105836 ONTARIO INC.



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       WOLVERINE JOINING TECHNOLOGIES
                                       (CANADA) INC.



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       CANADIAN SUBSIDIARY BORROWERS:

                                       1263143 ONTARIO INC.



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       1158909 ONTARIO INC.



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       WOLVERINE TUBE (CANADA) INC.



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------

<PAGE>

                                       LENDERS:

                                       WACHOVIA BANK, NATIONAL
                                       ASSOCIATION, in its capacity as
                                       Administrative Agent and as a Lender



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------

<PAGE>

                                       CONGRESS FINANCIAL CORPORATION
                                       (CANADA),
                                       in its capacity as Canadian Agent and as
                                       a Lender



                                       By:
                                          --------------------------------------
                                       Name:
                                            ------------------------------------
                                       Title:
                                             -----------------------------------

                              [signature pages end]