<PAGE>   1
   As filed with the Securities and Exchange Commission on September 22, 2000

                                                    Registration No.333-
===============================================================================


                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                        -------------------------------


                                    FORM S-8
                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933

                        -------------------------------


                                NATCO GROUP INC.
             (Exact name of registrant as specified in its charter)

               DELAWARE                                   22-2906892
    (State or other jurisdiction of                    (I.R.S. Employer
    incorporation or organization)                    Identification No.)

                          2950 N. LOOP WEST, 7th FLOOR
                              HOUSTON, TEXAS 77092
          (Address of principal executive offices, including zip code)

                        -------------------------------

                           NATCO GROUP PROFIT SHARING
                                AND SAVINGS PLAN

                            (Full title of the plan)

                                J. MICHAEL MAYER
               SENIOR VICE PRESIDENT AND CHIEF FINANCIAL OFFICER
                                NATCO GROUP INC.
                            BROOKHOLLOW CENTRAL III
                          2950 N. LOOP WEST, 7th FLOOR
                              HOUSTON, TEXAS 77092
                    (Name and address of agent for service)

                                 (713) 683-9292
         (Telephone number, including area code, of agent for service)

                                   Copies to:

                              William E. Joor III
                             Vinson & Elkins L.L.P.
                       2300 First City Tower, 1001 Fannin
                              Houston, Texas 77002
                                 (713) 758-2222


<PAGE>   2

                        CALCULATION OF REGISTRATION FEE
<TABLE>
<CAPTION>
======================================================================================================================
                                                                                     PROPOSED
                 TITLE OF                  MAXIMUM              PROPOSED              MAXIMUM
             SECURITIES TO BE            AMOUNT TO BE       MAXIMUM OFFERING         AGGREGATE           AMOUNT OF
                REGISTERED             REGISTERED (1)      PRICE PER SHARE (2)    OFFERING PRICE     REGISTRATION FEE
----------------------------------------------------------------------------------------------------------------------
<S>                                    <C>                 <C>                    <C>                <C>
NATCO Group Profit Sharing and        1,000,000 shares           $8.625              $8,625,000           $2,277
   Savings Plan, Class A Common
   Stock, $0.01 par value............
======================================================================================================================
</TABLE>

(1) Pursuant to Rule 416(c) of the Securities Act of 1933, as amended, this
Registration Statement shall also cover any additional shares of Class A Common
Stock which become issuable under the NATCO Group Profit Sharing and Savings
Plan by reason of any stock dividend, stock split, recapitalization or any other
similar transaction effected without the receipt of consideration which results
in an increase in the number of the Registrant's outstanding shares of Class A
Common Stock.

(2) Estimated in accordance with Rule 457(h) under the Securities Act of 1933
solely for the purpose of calculating the registration fee. Specifically, the
offering price per share is based on the average of the high and low prices of
NATCO Group Inc. Class A Common Stock reported on the New York Stock Exchange as
of September 21, 2000.

-------------------------------------------------------------------------------
                                      -2-

<PAGE>   3
                                    PART II
              INFORMATION REQUIRED IN THIS REGISTRATION STATEMENT

ITEM 3.    INCORPORATION OF DOCUMENTS BY REFERENCE.

      The following are incorporated by reference and made a part of this
prospectus: (i) the NATCO Group Inc. (the "Company") Annual Report on Form 10-K
for the year ended December 31, 1999; (ii) the Company's Quarterly Report on
Form 10-Q for the quarter ended March 31, 2000; (iii) the Company's Quarterly
Report on Form 10-Q for the quarter ended June 30, 2000; (iv) the Description
of the Company's Capital Stock contained in our Registration Statement on Form
8-A filed with the Commission under Section 12 of the Securities Exchange Act of
1934 (the "Exchange Act") and declared effective on January 27, 2000, including
any amendments or reports filed for the purpose of updating such description;
and (v) the Company's Current Report on Form 8-K filed with the Commission on
April 10, 2000.

      All documents we have filed pursuant to Sections 13(a), 13(c), 14 and
15(d) of the Exchange Act subsequent to the effective date of this Registration
Statement, prior to the filing of a post-effective amendment to this
Registration Statement indicating that all securities offered by this
prospectus have been sold or deregistering all securities then remaining
unsold, shall be deemed to be incorporated by reference of this prospectus and
to be a part of this prospectus from the date of filing of such documents. Any
statement contained herein or in any document incorporated or deemed to be
incorporated by reference shall be deemed to be modified or superseded for
purposes of this Registration Statement to the extent that a statement
contained in this prospectus or in any other subsequently filed document which
also is or is deemed to be incorporated by reference modifies or supersedes
such statement. Any such statement so modified or superseded shall not be
deemed to constitute a part of this Registration Statement, except as so
modified or superseded.

ITEM 4.    DESCRIPTION OF SECURITIES.

      Not applicable.

ITEM 5.    INTERESTS OF NAMED EXPERTS AND COUNSEL.

      Not applicable.

ITEM 6.    INDEMNIFICATION OF DIRECTORS AND OFFICERS.

      Our Restated Certificate of Incorporation, a copy of which is filed as
Exhibit 3.1 to our Registration Statement on Form S-1 (No. 333-48851), provides
that, to the fullest extent permitted by the Delaware General Corporation Law as
the same exists or may be hereafter amended (the "DGCL"), no director of the
Company shall be personally liable to the Company or its stockholders for
monetary damages for any breach of fiduciary duty by such a director as a
director. Article VI of our Amended and Restated Bylaws also provides that we
may maintain insurance, at our own expense, to protect the Company and any
director, officer, employee or agent of the Company or of another entity against
any expense, liability, or loss, regardless of whether the Company would have
power to indemnify such person against such expense, liability or loss under the
DGCL.

      Section 145 of the DGCL authorizes, inter alia, a corporation to
indemnify any person who was or is a party or is threatened to be made a party
to any threatened, pending or completed action, suit or proceeding, whether
civil, criminal, administrative or investigative (other than an action by or in
the right of the corporation), by reason of the fact that the person is or was
an officer or director of such corporation, or is or was serving at the request
of that corporation as a director, officer, employee or agent of another
corporation, partnership, joint venture, trust or other enterprise, against
expenses (including attorneys' fees), judgments, fines and amounts paid in
settlement actually and reasonably incurred by such person in connection with
such action, suit or proceeding, if he acted in good faith and in a manner he
reasonably believed to be in or not opposed to the best interests of the
corporation and, with respect to any criminal action or proceeding, had no
reasonable cause to believe his conduct was unlawful. A Delaware corporation
may indemnify past or present officers and directors of that corporation or of
another corporation or other enterprise at the former corporation's request, in
an action by or in the right of the corporation to procure a judgment in its
favor under the same conditions, except that no indemnification is permitted
without judicial approval if that person is adjudged to be liable to the
corporation. Where an officer or director is successful


                                      -3-

<PAGE>   4



on the merits or otherwise in defense of any action referred to above, or in
defense of any action referred to above, or in defense of any claim, issue or
matter therein, the corporation must indemnify him against the expenses
(including attorneys' fees) which he actually and reasonably incurred in
connection therewith. Section 145 further provides that any indemnification
shall be made by the corporation only as authorized in each specific case upon
a determination by the (i) stockholders, (ii) Board of Directors by a majority
vote of a quorum consisting of directors who were not parties to such action,
suit or proceeding or (iii) independent counsel if a quorum of disinterested
directors so directs. Section 145 provides that indemnification pursuant to its
provision is not exclusive of other rights of indemnification to which a person
may be entitled under any bylaw, agreement, vote of stockholders or
disinterested directors or otherwise.

      Section 145 of the DGCL also empowers us to purchase and maintain
insurance on behalf of any person who is or was an officer or director of the
Company against liability asserted against or incurred by him in any such
capacity, whether or not we would have the power to indemnify such officer or
director against such liability under the provisions of Section 145.

      In addition, the Company has entered into indemnification agreements with
our directors and officers. These indemnification agreements, among other
things, indemnify our directors and officers for certain expenses (including
attorneys' fees), judgments, fines, and settlement payments incurred by such
person in any action, including in some circumstances an action by or in the
right of the Company, in connection with the good faith performance of their
duties as a director or officer. The indemnification agreements also provide for
the advance payment by the Company of defense expenses incurred by the director
or officer; however, the affected director or officer must undertake to repay
such amounts if it is ultimately determined that such director or officer is not
entitled to be indemnified.


ITEM 7.    EXEMPTION FROM REGISTRATION CLAIMED.

      Not applicable.

ITEM 8.    EXHIBITS.

      Unless otherwise indicated below as being incorporated by reference to
another filing of the Company with the Commission, each of the following
exhibits is filed herewith:

<TABLE>
<S>           <C>
     3.1       Certificate of Incorporation of the Company, as amended (filed with the Commission as Exhibit
               3.1 to the Company's Registration Statement on Form S-1 (No. 333-48851) and incorporated
               herein by reference)

     3.2       Certificate of Designation of Series A Junior Participating Preference Stock (filed with the
               Commission as Exhibit 3.2 to the Company's Registration Statement on Form S-1 (No. 333-
               48851) and incorporated herein by reference)

     3.3       Amended and Restated Bylaws of the Company (filed with the Commission as Exhibit 3.3 to the
               Company's Registration Statement on Form S-1 (No. 333-48851) and incorporated herein by
               reference)

     4.1       Specimen Common Stock certificate (filed with the Commission as Exhibit 4.1 to the Company's
               Registration Statement on Form S-1 (No. 333-48851) and incorporated herein by reference)

     4.2       Directors Compensation Plan (filed with the Commission as Exhibit 10.1 to the Company's
               Registration Statement on Form S-1 (No. 333-48851) and incorporated by reference)
</TABLE>


                                      -4-

<PAGE>   5

<TABLE>
<S>           <C>
     4.3       Employee Stock Incentive Plan (filed with the Commission as Exhibit 10.3 to
               the Company's Registration Statement Form S-1 (No. 333-48851) and
               incorporated by reference)

     4.4       NATCO Stock Option Arrangement (filed with the Commission as Exhibit 10.4 to
               the Company's Registration Statement on Form S-8 (No. 333-32020) and incorporated
               by reference)

     4.5       NATCO Profit Sharing and Savings Plan, as Amended and Restated

     4.6       First Amendment to NATCO Profit Sharing and Savings Plan

     4.7       Stock Trust Agreement

     5.1       Opinion of Vinson & Elkins L.L.P.

    23.1       Consent of KPMG LLP

    23.2       Consent of Vinson & Elkins L.L.P. (included in Exhibit 5.1)

    24.1       Powers of Attorney (included on the signature page to this Registration Statement)
</TABLE>


                                  UNDERTAKINGS

      The undersigned Registrant hereby undertakes:

           (1) To file, during any period in which offers or sales are being
      made, a post-effective amendment to this registration statement:

                (a)  To include any prospectus required by Section 10(a)(3) of
           the Securities Act;

                (b) To reflect in the prospectus any facts or events arising
           after the effective date of this Registration Statement (or the most
           recent post-effective amendment thereof) which, individually or in
           the aggregate, represent a fundamental change in the information set
           forth in this Registration Statement;

                (c) To include any material information with respect to the
           plan of distribution not previously disclosed in this Registration
           Statement or any material change to such information in this
           Registration Statement;

      provided, however, that paragraphs (1)(a) and (1)(b) do not apply if the
      information required to be included in a post-effective amendment by
      those paragraphs is contained in periodic reports filed by the Registrant
      pursuant to Section 13 or Section 15(d) of the Exchange Act that are
      incorporated by reference in this Registration Statement.

           (2) That, for the purpose of determining any liability under the
      Securities Act, each such post-effective amendment shall be deemed to be
      a new registration statement relating to the securities offered therein,
      and the offering of such securities at that time shall be deemed to be
      the initial bona fide offering thereof.

           (3) To remove from registration by means of a post-effective
      amendment any of the securities being registered which remain unsold at
      the termination of the offering.

           (4) That, for the purposes of determining any liability under the
      Securities Act, each filing of the Registrant's annual report pursuant to
      Section 13(a) or Section 15(d) of the Exchange Act (and, where
      applicable, each filing of an employee benefit plan's annual report
      pursuant to Section 15(d) of the Exchange Act) that is incorporated by
      reference in this Registration Statement shall be deemed to be a new
      registration statement relating to the securities offered therein, and
      the offering of such securities at that time shall be deemed to be the
      initial bona fide offering thereof.

           (5) Insofar as indemnification for liabilities arising under the
      Securities Act may be permitted to directors, officers and controlling
      persons of the Registrant pursuant to the foregoing provisions or
      otherwise, the Registrant has been advised that in the opinion of the
      Commission such indemnification is against public policy

                                      -5-

<PAGE>   6



      as expressed in the Securities Act and is, therefore, unenforceable. In
      the event that a claim for indemnification against such liabilities
      (other than the payment by the Registrant of expenses incurred or paid by
      a director, officer or controlling person of the Registrant in the
      successful defense of any action, suit or proceeding) is asserted by such
      director, officer or controlling person in connection with the securities
      being registered, the Registrant will, unless in the opinion of its
      counsel the matter has been settled by controlling precedent, submit to a
      court of appropriate jurisdiction the question whether such
      indemnification by it is against public policy as expressed in the
      Securities Act and will be governed by the final adjudication of such
      issue.



                                      -6-

<PAGE>   7
                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the
Registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-8 and has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Houston, State of Texas, on the 22nd day of
September, 2000.

                                        NATCO Group Inc.

                                        By:        /s/ NATHANIEL A. GREGORY
                                            -------------------------------
                                                   Nathaniel A. Gregory
                                                   Chief Executive Officer and
                                                   Chairman of the Board


      KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Nathaniel A. Gregory and Daniel R. Carter
or either of them, his true and lawful attorney-in-fact and agent, with full
power of substitution, for him and in his name, place and stead, in any and all
capacities, to sign any and all amendments (including post-effective amendments)
to this Registration Statement on Form S-8, and to file the same with all
exhibits thereto, and other documents in connection therewith, with the
Securities and Exchange Commission, granting unto said attorney-in-fact and
agent full power and authority to do and perform each and every act and thing
requisite and ratifying and confirming all that said attorney-in-fact and agent
or his substitute or substitutes may lawfully do or cause to be done by virtue
hereof.

      Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the 22nd day of September, 2000.


          SIGNATURE                                    TITLE
          ---------                                    -----

  /s/ NATHANIEL A. GREGORY                   Chairman of the Board and
 --------------------------                  Chief Executive Officer
    Nathaniel A. Gregory                     (Principal Executive Officer)


    /s/ J. MICHAEL MAYER                     Senior Vice President and
   ----------------------                    Chief Financial Officer
      J. Michael Mayer                       (Principal Financial Officer)


      /s/ RYAN S. LILES                      Vice President and Controller
     -------------------                     (Principal Accounting Officer)
        Ryan S. Liles


 /s/ HERBERT S. WINOKUR, JR.                 Director
----------------------------
   Herbert S. Winokur, Jr.


     /s/ JOHN U. CLARKE                      Director
    --------------------
       John U. Clarke


   /s/ PATRICK M. MCCARTHY
  -------------------------                  Director and President
     Patrick M. McCarthy


     /s/ HOWARD I. BULL                      Director
    --------------------
       Howard I. Bull


     /s/ KEITH K. ALLAN                      Director
    --------------------
        Keith K. Allan


  /s/ GEORGE K. HICKOX, JR.                  Director
 --------------------------
    George K. Hickox, Jr.

                                      -7-

<PAGE>   8


                               INDEX TO EXHIBITS
<TABLE>
<S>       <C>

  3.1      Certificate of Incorporation of the Company, as amended (filed with the Commission as
           Exhibit 3.1 to the Company's Registration Statement on Form S-1 (No. 333-48851) and
           incorporated herein by reference)

  3.2      Certificate of Designation of Series A Junior Participating Preference Stock (filed with the
           Commission as Exhibit 3.2 to the Company's Registration Statement on Form S-1 (No. 48851)
           and incorporated herein by reference)

  3.3      Amended and Restated Bylaws of the Company (filed with the Commission as Exhibit 3.3 to the
           Company's Registration Statement on Form S-1 (No. 333-48851) and incorporated herein by
           reference)

  4.1      Specimen Common Stock certificate (filed with the Commission as Exhibit 4.1 to the Company's
           Registration Statement on Form S-1 (No. 333-48851) and incorporated herein by reference)

  4.2      Directors Compensation Plan (filed with the Commission as Exhibit 10.1 to the Company's
           Registration Statement on form S-1 (No. 333-48851) and incorporated by reference)

  4.3      Employee Stock Incentive Plan (filed with the Commission as Exhibit 10.3 to the Company's
           Registration Statement Form S-1 (No. 333-48851) and incorporated by reference)

  4.4      NATCO Stock Option Arrangement (filed with the Commission as Exhibit 10.4 to
           the Company's Registration Statement on Form S-8 (No. 333-32020) and incorporated
           by reference)

  4.5      NATCO Profit Sharing and Savings Plan, as Amended and Restated

  4.6      First Amendment to NATCO Profit Sharing and Savings Plan

  4.7      Stock Trust Agreement

  5.1      Opinion of Vinson & Elkins L.L.P.

 23.1      Consent of KPMG LLP

 23.2      Consent of Vinson & Elkins L.L.P. (included in Exhibit 5.1

 24.1      Powers of Attorney (included on the signature page to this Registration Statement)
</TABLE>




                                      -8-
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{"company-data": {"conformed-name": "NATCO GROUP INC", "cik": "0001057693", "assigned-sic": "3443", "irs-number": "222906892", "state-of-incorporation": "DE", "fiscal-year-end": "0331"}, "filing-values": {"form-type": "S-8", "act": "33", "file-number": "333-46410", "film-number": "727219"}, "business-address": {"street1": "BROOKHOLLOW CENTRAL III", "street2": "2950 NORTH LOOP WEST STE 750", "city": "HOUSTON", "state": "TX", "zip": "77092", "phone": "7136839292"}, "mail-address": {"street1": "BROOKHOLLOW CENTERL III", "street2": "2950 NORTH LOOP WEST STE 750", "city": "HOUSTON", "state": "TX", "zip": "77092"}}
1
   As filed with the Securities and Exchange Commission on September 22, 2000

                                                    Registration No.333-
===============================================================================

                       SECURITIES AND EXCHANGE COMMISSION
                             Washington, D.C. 20549

                        -------------------------------

                                    FORM S-8
                             REGISTRATION STATEMENT
                                     UNDER
                           THE SECURITIES ACT OF 1933

                        -------------------------------

                                NATCO GROUP INC.
             (Exact name of registrant as specified in its charter)

               DELAWARE                                   22-2906892
    (State or other jurisdiction of                    (I.R.S. Employer
    incorporation or organization)                    Identification No.)

                          2950 N. LOOP WEST, 7th FLOOR
                              HOUSTON, TEXAS 77092
          (Address of principal executive offices, including zip code)

                        -------------------------------

                           NATCO GROUP PROFIT SHARING
                                AND SAVINGS PLAN

                            (Full title of the plan)

                                J. MICHAEL MAYER
               SENIOR VICE PRESIDENT AND CHIEF FINANCIAL OFFICER
                                NATCO GROUP INC.
                            BROOKHOLLOW CENTRAL III
                          2950 N. LOOP WEST, 7th FLOOR
                              HOUSTON, TEXAS 77092
                    (Name and address of agent for service)

                                 (713) 683-9292
         (Telephone number, including area code, of agent for service)

                                   Copies to:

                              William E. Joor III
                             Vinson & Elkins L.L.P.
                       2300 First City Tower, 1001 Fannin
                              Houston, Texas 77002
                                 (713) 758-2222
2

                        CALCULATION OF REGISTRATION FEE
======================================================================================================================
                                                                                     PROPOSED
                 TITLE OF                  MAXIMUM              PROPOSED              MAXIMUM
             SECURITIES TO BE            AMOUNT TO BE       MAXIMUM OFFERING         AGGREGATE           AMOUNT OF
                REGISTERED             REGISTERED (1)      PRICE PER SHARE (2)    OFFERING PRICE     REGISTRATION FEE
----------------------------------------------------------------------------------------------------------------------
NATCO Group Profit Sharing and        1,000,000 shares           $8.625              $8,625,000           $2,277
   Savings Plan, Class A Common
   Stock, $0.01 par value............
======================================================================================================================
(1) Pursuant to Rule 416(c) of the Securities Act of 1933, as amended, this
Registration Statement shall also cover any additional shares of Class A Common
Stock which become issuable under the NATCO Group Profit Sharing and Savings
Plan by reason of any stock dividend, stock split, recapitalization or any other
similar transaction effected without the receipt of consideration which results
in an increase in the number of the Registrant's outstanding shares of Class A
Common Stock.

(2) Estimated in accordance with Rule 457(h) under the Securities Act of 1933
solely for the purpose of calculating the registration fee. Specifically, the
offering price per share is based on the average of the high and low prices of
NATCO Group Inc. Class A Common Stock reported on the New York Stock Exchange as
of September 21, 2000.

-------------------------------------------------------------------------------
                                      -2-
3
                                    PART II
              INFORMATION REQUIRED IN THIS REGISTRATION STATEMENT

ITEM 3.    INCORPORATION OF DOCUMENTS BY REFERENCE.

      The following are incorporated by reference and made a part of this
prospectus: (i) the NATCO Group Inc. (the "Company") Annual Report on Form 10-K
for the year ended December 31, 1999; (ii) the Company's Quarterly Report on
Form 10-Q for the quarter ended March 31, 2000; (iii) the Company's Quarterly
Report on Form 10-Q for the quarter ended June 30, 2000; (iv) the Description
of the Company's Capital Stock contained in our Registration Statement on Form
8-A filed with the Commission under Section 12 of the Securities Exchange Act of
1934 (the "Exchange Act") and declared effective on January 27, 2000, including
any amendments or reports filed for the purpose of updating such description;
and (v) the Company's Current Report on Form 8-K filed with the Commission on
April 10, 2000.

      All documents we have filed pursuant to Sections 13(a), 13(c), 14 and
15(d) of the Exchange Act subsequent to the effective date of this Registration
Statement, prior to the filing of a post-effective amendment to this
Registration Statement indicating that all securities offered by this
prospectus have been sold or deregistering all securities then remaining
unsold, shall be deemed to be incorporated by reference of this prospectus and
to be a part of this prospectus from the date of filing of such documents. Any
statement contained herein or in any document incorporated or deemed to be
incorporated by reference shall be deemed to be modified or superseded for
purposes of this Registration Statement to the extent that a statement
contained in this prospectus or in any other subsequently filed document which
also is or is deemed to be incorporated by reference modifies or supersedes
such statement. Any such statement so modified or superseded shall not be
deemed to constitute a part of this Registration Statement, except as so
modified or superseded.

ITEM 4.    DESCRIPTION OF SECURITIES.

      Not applicable.

ITEM 5.    INTERESTS OF NAMED EXPERTS AND COUNSEL.

      Not applicable.

ITEM 6.    INDEMNIFICATION OF DIRECTORS AND OFFICERS.

      Our Restated Certificate of Incorporation, a copy of which is filed as
Exhibit 3.1 to our Registration Statement on Form S-1 (No. 333-48851), provides
that, to the fullest extent permitted by the Delaware General Corporation Law as
the same exists or may be hereafter amended (the "DGCL"), no director of the
Company shall be personally liable to the Company or its stockholders for
monetary damages for any breach of fiduciary duty by such a director as a
director. Article VI of our Amended and Restated Bylaws also provides that we
may maintain insurance, at our own expense, to protect the Company and any
director, officer, employee or agent of the Company or of another entity against
any expense, liability, or loss, regardless of whether the Company would have
power to indemnify such person against such expense, liability or loss under the
DGCL.

      Section 145 of the DGCL authorizes, inter alia, a corporation to
indemnify any person who was or is a party or is threatened to be made a party
to any threatened, pending or completed action, suit or proceeding, whether
civil, criminal, administrative or investigative (other than an action by or in
the right of the corporation), by reason of the fact that the person is or was
an officer or director of such corporation, or is or was serving at the request
of that corporation as a director, officer, employee or agent of another
corporation, partnership, joint venture, trust or other enterprise, against
expenses (including attorneys' fees), judgments, fines and amounts paid in
settlement actually and reasonably incurred by such person in connection with
such action, suit or proceeding, if he acted in good faith and in a manner he
reasonably believed to be in or not opposed to the best interests of the
corporation and, with respect to any criminal action or proceeding, had no
reasonable cause to believe his conduct was unlawful. A Delaware corporation
may indemnify past or present officers and directors of that corporation or of
another corporation or other enterprise at the former corporation's request, in
an action by or in the right of the corporation to procure a judgment in its
favor under the same conditions, except that no indemnification is permitted
without judicial approval if that person is adjudged to be liable to the
corporation. Where an officer or director is successful

                                      -3-
4

on the merits or otherwise in defense of any action referred to above, or in
defense of any action referred to above, or in defense of any claim, issue or
matter therein, the corporation must indemnify him against the expenses
(including attorneys' fees) which he actually and reasonably incurred in
connection therewith. Section 145 further provides that any indemnification
shall be made by the corporation only as authorized in each specific case upon
a determination by the (i) stockholders, (ii) Board of Directors by a majority
vote of a quorum consisting of directors who were not parties to such action,
suit or proceeding or (iii) independent counsel if a quorum of disinterested
directors so directs. Section 145 provides that indemnification pursuant to its
provision is not exclusive of other rights of indemnification to which a person
may be entitled under any bylaw, agreement, vote of stockholders or
disinterested directors or otherwise.

      Section 145 of the DGCL also empowers us to purchase and maintain
insurance on behalf of any person who is or was an officer or director of the
Company against liability asserted against or incurred by him in any such
capacity, whether or not we would have the power to indemnify such officer or
director against such liability under the provisions of Section 145.

      In addition, the Company has entered into indemnification agreements with
our directors and officers. These indemnification agreements, among other
things, indemnify our directors and officers for certain expenses (including
attorneys' fees), judgments, fines, and settlement payments incurred by such
person in any action, including in some circumstances an action by or in the
right of the Company, in connection with the good faith performance of their
duties as a director or officer. The indemnification agreements also provide for
the advance payment by the Company of defense expenses incurred by the director
or officer; however, the affected director or officer must undertake to repay
such amounts if it is ultimately determined that such director or officer is not
entitled to be indemnified.

ITEM 7.    EXEMPTION FROM REGISTRATION CLAIMED.

      Not applicable.

ITEM 8.    EXHIBITS.

      Unless otherwise indicated below as being incorporated by reference to
another filing of the Company with the Commission, each of the following
exhibits is filed herewith:
3.1       Certificate of Incorporation of the Company, as amended (filed with the Commission as Exhibit
               3.1 to the Company's Registration Statement on Form S-1 (No. 333-48851) and incorporated
               herein by reference)

     3.2       Certificate of Designation of Series A Junior Participating Preference Stock (filed with the
               Commission as Exhibit 3.2 to the Company's Registration Statement on Form S-1 (No. 333-
               48851) and incorporated herein by reference)

     3.3       Amended and Restated Bylaws of the Company (filed with the Commission as Exhibit 3.3 to the
               Company's Registration Statement on Form S-1 (No. 333-48851) and incorporated herein by
               reference)

     4.1       Specimen Common Stock certificate (filed with the Commission as Exhibit 4.1 to the Company's
               Registration Statement on Form S-1 (No. 333-48851) and incorporated herein by reference)

     4.2       Directors Compensation Plan (filed with the Commission as Exhibit 10.1 to the Company's
               Registration Statement on Form S-1 (No. 333-48851) and incorporated by reference)
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5
4.3       Employee Stock Incentive Plan (filed with the Commission as Exhibit 10.3 to
               the Company's Registration Statement Form S-1 (No. 333-48851) and
               incorporated by reference)

     4.4       NATCO Stock Option Arrangement (filed with the Commission as Exhibit 10.4 to
               the Company's Registration Statement on Form S-8 (No. 333-32020) and incorporated
               by reference)

     4.5       NATCO Profit Sharing and Savings Plan, as Amended and Restated

     4.6       First Amendment to NATCO Profit Sharing and Savings Plan

     4.7       Stock Trust Agreement

     5.1       Opinion of Vinson & Elkins L.L.P.

    23.1       Consent of KPMG LLP

    23.2       Consent of Vinson & Elkins L.L.P. (included in Exhibit 5.1)

    24.1       Powers of Attorney (included on the signature page to this Registration Statement)
UNDERTAKINGS

      The undersigned Registrant hereby undertakes:

           (1) To file, during any period in which offers or sales are being
      made, a post-effective amendment to this registration statement:

                (a)  To include any prospectus required by Section 10(a)(3) of
           the Securities Act;

                (b) To reflect in the prospectus any facts or events arising
           after the effective date of this Registration Statement (or the most
           recent post-effective amendment thereof) which, individually or in
           the aggregate, represent a fundamental change in the information set
           forth in this Registration Statement;

                (c) To include any material information with respect to the
           plan of distribution not previously disclosed in this Registration
           Statement or any material change to such information in this
           Registration Statement;

      provided, however, that paragraphs (1)(a) and (1)(b) do not apply if the
      information required to be included in a post-effective amendment by
      those paragraphs is contained in periodic reports filed by the Registrant
      pursuant to Section 13 or Section 15(d) of the Exchange Act that are
      incorporated by reference in this Registration Statement.

           (2) That, for the purpose of determining any liability under the
      Securities Act, each such post-effective amendment shall be deemed to be
      a new registration statement relating to the securities offered therein,
      and the offering of such securities at that time shall be deemed to be
      the initial bona fide offering thereof.

           (3) To remove from registration by means of a post-effective
      amendment any of the securities being registered which remain unsold at
      the termination of the offering.

           (4) That, for the purposes of determining any liability under the
      Securities Act, each filing of the Registrant's annual report pursuant to
      Section 13(a) or Section 15(d) of the Exchange Act (and, where
      applicable, each filing of an employee benefit plan's annual report
      pursuant to Section 15(d) of the Exchange Act) that is incorporated by
      reference in this Registration Statement shall be deemed to be a new
      registration statement relating to the securities offered therein, and
      the offering of such securities at that time shall be deemed to be the
      initial bona fide offering thereof.

           (5) Insofar as indemnification for liabilities arising under the
      Securities Act may be permitted to directors, officers and controlling
      persons of the Registrant pursuant to the foregoing provisions or
      otherwise, the Registrant has been advised that in the opinion of the
      Commission such indemnification is against public policy

                                      -5-
6

      as expressed in the Securities Act and is, therefore, unenforceable. In
      the event that a claim for indemnification against such liabilities
      (other than the payment by the Registrant of expenses incurred or paid by
      a director, officer or controlling person of the Registrant in the
      successful defense of any action, suit or proceeding) is asserted by such
      director, officer or controlling person in connection with the securities
      being registered, the Registrant will, unless in the opinion of its
      counsel the matter has been settled by controlling precedent, submit to a
      court of appropriate jurisdiction the question whether such
      indemnification by it is against public policy as expressed in the
      Securities Act and will be governed by the final adjudication of such
      issue.

                                      -6-
7
                                   SIGNATURES

      Pursuant to the requirements of the Securities Act of 1933, the
Registrant certifies that it has reasonable grounds to believe that it meets
all of the requirements for filing on Form S-8 and has duly caused this
Registration Statement to be signed on its behalf by the undersigned, thereunto
duly authorized, in the City of Houston, State of Texas, on the 22nd day of
September, 2000.

                                        NATCO Group Inc.

                                        By:        /s/ NATHANIEL A. GREGORY
                                            -------------------------------
                                                   Nathaniel A. Gregory
                                                   Chief Executive Officer and
                                                   Chairman of the Board

      KNOW ALL PERSONS BY THESE PRESENTS, that each person whose signature
appears below constitutes and appoints Nathaniel A. Gregory and Daniel R. Carter
or either of them, his true and lawful attorney-in-fact and agent, with full
power of substitution, for him and in his name, place and stead, in any and all
capacities, to sign any and all amendments (including post-effective amendments)
to this Registration Statement on Form S-8, and to file the same with all
exhibits thereto, and other documents in connection therewith, with the
Securities and Exchange Commission, granting unto said attorney-in-fact and
agent full power and authority to do and perform each and every act and thing
requisite and ratifying and confirming all that said attorney-in-fact and agent
or his substitute or substitutes may lawfully do or cause to be done by virtue
hereof.

      Pursuant to the requirements of the Securities Act of 1933, this
registration statement has been signed by the following persons in the
capacities and on the 22nd day of September, 2000.

          SIGNATURE                                    TITLE
          ---------                                    -----

  /s/ NATHANIEL A. GREGORY                   Chairman of the Board and
 --------------------------                  Chief Executive Officer
    Nathaniel A. Gregory                     (Principal Executive Officer)

    /s/ J. MICHAEL MAYER                     Senior Vice President and
   ----------------------                    Chief Financial Officer
      J. Michael Mayer                       (Principal Financial Officer)

      /s/ RYAN S. LILES                      Vice President and Controller
     -------------------                     (Principal Accounting Officer)
        Ryan S. Liles

 /s/ HERBERT S. WINOKUR, JR.                 Director
----------------------------
   Herbert S. Winokur, Jr.

     /s/ JOHN U. CLARKE                      Director
    --------------------
       John U. Clarke

   /s/ PATRICK M. MCCARTHY
  -------------------------                  Director and President
     Patrick M. McCarthy

     /s/ HOWARD I. BULL                      Director
    --------------------
       Howard I. Bull

     /s/ KEITH K. ALLAN                      Director
    --------------------
        Keith K. Allan

  /s/ GEORGE K. HICKOX, JR.                  Director
 --------------------------
    George K. Hickox, Jr.

                                      -7-
8

                               INDEX TO EXHIBITS
3.1      Certificate of Incorporation of the Company, as amended (filed with the Commission as
           Exhibit 3.1 to the Company's Registration Statement on Form S-1 (No. 333-48851) and
           incorporated herein by reference)

  3.2      Certificate of Designation of Series A Junior Participating Preference Stock (filed with the
           Commission as Exhibit 3.2 to the Company's Registration Statement on Form S-1 (No. 48851)
           and incorporated herein by reference)

  3.3      Amended and Restated Bylaws of the Company (filed with the Commission as Exhibit 3.3 to the
           Company's Registration Statement on Form S-1 (No. 333-48851) and incorporated herein by
           reference)

  4.1      Specimen Common Stock certificate (filed with the Commission as Exhibit 4.1 to the Company's
           Registration Statement on Form S-1 (No. 333-48851) and incorporated herein by reference)

  4.2      Directors Compensation Plan (filed with the Commission as Exhibit 10.1 to the Company's
           Registration Statement on form S-1 (No. 333-48851) and incorporated by reference)

  4.3      Employee Stock Incentive Plan (filed with the Commission as Exhibit 10.3 to the Company's
           Registration Statement Form S-1 (No. 333-48851) and incorporated by reference)

  4.4      NATCO Stock Option Arrangement (filed with the Commission as Exhibit 10.4 to
           the Company's Registration Statement on Form S-8 (No. 333-32020) and incorporated
           by reference)

  4.5      NATCO Profit Sharing and Savings Plan, as Amended and Restated

  4.6      First Amendment to NATCO Profit Sharing and Savings Plan

  4.7      Stock Trust Agreement

  5.1      Opinion of Vinson & Elkins L.L.P.

 23.1      Consent of KPMG LLP

 23.2      Consent of Vinson & Elkins L.L.P. (included in Exhibit 5.1

 24.1      Powers of Attorney (included on the signature page to this Registration Statement)
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