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                                                                    Exhibit 3.22

                                     BY-LAWS
                                       OF
                                 VANTRANS, INC.
                            (a Delaware corporation)
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                                    ARTICLE I
                                     OFFICES

      Section 1. Registered Office. The registered office shall be established
and maintained at No. 100 West Tenth Street, Wilmington, Delaware. The
Corporation Trust Company shall be the registered agent of this corporation in
charge thereof.

      Section 2. Other Offices. The corporation may have other offices, either
within or without the State of Delaware, at such place or places as the Board of
Directors may from time to time determine or the business of the corporation may
require.

                                   ARTICLE II
                            MEETINGS OF STOCKHOLDERS

      Section 1. Annual Meetings. Annual meetings of stockholders for the
election of directors and for such other business as may be stated in the notice
of the meeting shall be held at such place, either within or without the 
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State of Delaware, and at such time and date as the Board of Directors, by
resolution, shall determine and as set forth in the notice of the meeting.

      Section 2. Other Meetings. Meetings of stockholders for any purpose other
than the election of directors may be held at such time and place, within or
without the State of Delaware, as shall be stated in the notice of the meeting.

      Section 3. Voting. Each stockholder entitled to vote in accordance with
the terms of the Certificate of Incorporation and in accordance with the
provisions of these By-Laws shall be entitled to one vote, in person or by
proxy, for each share of stock entitled to vote held by such stockholder, but no
proxy shall be voted after three years from its date unless such proxy provides
for a longer period. Upon the demand of any stockholder, the vote for directors
and the vote upon any question before the meeting shall be by ballot. All
elections for directors shall be decided by plurality vote; all other questions
shall be decided by majority vote except as otherwise provided by the
Certificate of Incorporation or the laws of the State of Delaware.

      A complete list of the stockholders entitled to vote at the ensuing
election, arranged in alphabetical order, with the address of each, and the
number of shares held by each, shall be open to the examination of any
stockholder, for any 


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purpose germane to the meeting, during ordinary business hours, for a period of
at least ten days prior to the meeting, either at a place within the city where
the meeting is to be held, which place shall be specified in the notice of the
meeting, or, if not so specified, at the place where the meeting is to be held.
The list shall also be produced and kept at the time and place of the meeting
during the whole time thereof, and may be inspected by any stockholder who is
present.

            Section 4. Quorum. Except as otherwise required by law, by the
Certificate of Incorporation or by these by-laws, the presence, in person or by
proxy, of stockholders holding a majority of the stock of the corporation
entitled to vote shall constitute a quorum at all meetings of the stockholders.
In case a quorum shall not be present at any meeting, a majority in interest of
the stockholders entitled to vote thereat, present in person or by proxy, shall
have the power to adjourn the meeting from time to time, without notice other
than announcement at the meeting, until the requisite amount of stock entitled
to vote shall be present. At such adjourned meeting at which the requisite
amount of stock entitled to vote shall be represented, any business may be
transacted which might have been transacted at the meeting as originally
noticed; but only those stockholders entitled to vote at the meeting as
originally noticed shall 


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be entitled to vote at any adjournment or adjournments thereof.

      Section 5. Special Meetings. Special meetings of the stockholders for any
purpose or purposes may be called by the President or Secretary, or by
resolution of the directors.

      Section 6. Notice of Meetings. Written notice, stating the place, date and
time of the meeting, and the general nature of the business to be considered,
shall be given to each stockholder entitled to vote thereat at his address as it
appears on the records of the corporation, not less than ten nor more than fifty
days before the date of the meeting. No business other than that stated in the
notice shall be transacted at any meeting without the unanimous consent of all
the stockholders entitled to vote thereat.

      Section 7. Action Without Meeting. Unless otherwise provided by the
Certificate of Incorporation, any action required to be taken at any annual or
special meeting of stockholders, or any action which may be taken at any annual
or special meeting, may be taken without a meeting, without prior notice and
without a vote, if a consent in writing, setting forth the action so taken,
shall be signed by the holders of outstanding stock having not less than the
minimum number of votes that would be necessary to authorize 


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or take such action at a meeting at which all shares entitled to vote thereon
were present and voted. Prompt notice of the taking of the corporate action
without a meeting by less than unanimous written consent shall be given to those
stockholders who have not consented in writing.

                                   ARTICLE III
                                    DIRECTORS

      Section 1. Number and Term. The number of directors shall be not less than
two and not more than seven. The directors shall be elected at the annual
meeting of the stockholders and each director shall be elected to serve until
his successor shall be elected and qualified. Directors need not be
stockholders.

      Section 2. Removal. Any director or directors may be removed either for or
without cause at any time by the affirmative vote of the holders of a majority
of all the shares of stock outstanding and entitled to vote, at a special
meeting of the stockholders called for the purpose, and the vacancies thus
created may be filled, at the meeting held for the purpose of removal, by the
affirmative vote of a majority in interest of the stockholders entitled to vote.

      Section 3. Increase of Number. The number of directors may be increased by
amendment of these By-Laws by 


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the affirmative vote of a majority of the directors, though less than a quorum,
or, by the affirmative vote of a majority in interest of the stockholders, at
the annual meeting or at a special meeting called for that purpose, and by like
vote the additional directors may be chosen at such meeting to hold office until
the next annual election and until their successors shall have been elected and
qualified.

      Section 4. Powers. The Board of Directors shall exercise all of the powers
of the corporation except such as are by law or by the Certificate of
Incorporation of the corporation or by these By-Laws conferred upon or reserved
to the stockholders.

      Section 5. Committees. The Board of Directors may, by resolution or
resolutions passed by a majority of the whole board, designate one or more
committees, each committee to consist of two or more of the directors of the
corporation. The board may designate one or more directors as alternate members
of any committee, who may replace any absent or disqualified member at any
meeting of such committee or committees. The member or members thereof present
at any meeting and not disqualified from voting, whether or not he or they
constitute a quorum, may unanimously appoint another member of the Board of
Directors to act at the meeting in the place of any such absent or disqualified
member.


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      Any such committee, to the extent provided in the resolution of the Board
of Directors, or in these By-Laws, shall have and may exercise all the powers
and authority of the Board of Directors in the management of the business and
affairs of the corporation, and may authorize the seal of the corporation to be
affixed to all papers which may require it; but no such committee shall have the
power or authority to amend the Certificate of Incorporation, to adopt an
agreement of merger or consolidation, to recommend to the stockholders the sale,
lease or exchange of all or substantially all of the corporation's property and
assets, to recommend to the stockholders a dissolution of the corporation or a
revocation of a dissolution, or to amend the By-Laws of the corporation; and,
unless the resolution, these By-Laws, or the Certificate of Incorporation
expressly so provide, no such committee shall have the power or authority to
declare a dividend or to authorize the issuance of stock.

      Section 6. Meetings. The newly elected directors may hold their first
meeting for the purpose of organization and the transaction of business, if a
quorum be present, immediately after the annual meeting of the stockholders; or
the time and place of such meeting may be fixed by consent in writing of all the
directors.


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      Regular meetings of the directors may be held without notice at such
places and times as shall be determined from time to time by resolution of the
directors.

      Special meetings of the board may be called by the President or by the
Secretary on the written request of any two directors on at least two days'
notice to each director and shall be held at such place or places as may be
determined by the directors, or as shall be stated in the call of the meeting.

      Section 7. Quorum. One-third of the total number of directors shall
constitute a quorum for the transaction of business. If at any meeting of the
Board of Directors there shall be less than a quorum present, a majority of
those present may adjourn the meeting from time to time until a quorum is
obtained, and no further notice thereof need be given other than by announcement
at the meeting which shall be so adjourned.

      Section 8. Compensation. Directors shall not receive any stated salary for
their services as directors or as members of committees, but by resolution of
the Board of Directors a fixed fee and expenses of attendance may be allowed for
attendance at each meeting. Nothing herein contained shall be construed to
preclude any director from serving the corporation in any other capacity as an
officer, agent or otherwise, and receiving compensation therefor.


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      Section 9. Action Without Meeting. Any action required or permitted to be
taken at any meeting of the Board of Directors, or of any committee thereof, may
be taken without a meeting, if a written consent thereto is signed by all
members of the Board of Directors, or of such committee as the case may be, and
such written consent is filed with the minutes of proceedings of the Board of
Directors or committee.

      Section 10. Participation by Conference Telephone. Members of the Board of
Directors of the corporation, or any committee designated by such board, may
participate in a meeting of such board or committee by means of conference
telephone or similar communications equipment by means of which all persons
participating in the meeting can hear each other, and participation in a meeting
shall constitute presence in person at such meeting.

                                   ARTICLE IV
                                    OFFICERS

      Section 1. Officers. The officers of the corporation shall be a President,
a Treasurer, and a Secretary, all of whom shall be elected by the Board of
Directors and who shall hold office until their successors are elected and
qualified. In addition, the Board of Directors may elect a Chairman, one or more
Vice Presidents and such Assistant 


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Secretaries and Assistant Treasurers as they may deem proper. None of the
officers of the corporation need be directors. The officers shall be elected at
the first meeting of the Board of Directors after each annual meeting. More than
two offices may be held by the same person.

      Section 2. Other Officers and Agents. The Board of Directors may appoint
such other officers and agents as it may deem advisable, who shall hold their
offices for such terms and shall exercise such powers and perform such duties as
shall be determined from time to time by the Board of Directors.

      Section 3. Chairman. The Chairman of the Board of Directors, if one be
elected, shall preside at all meetings of the Board of Directors and he shall
have and perform such other duties as from time to time may be assigned to him
by the Board of Directors.

      Section 4. President. The President shall be the chief executive officer
of the corporation and shall have the general powers and duties of supervision
and management usually vested in the office of president of a corporation. He
shall preside at all meetings of the stockholders if present thereat, and, in
the absence or non-election of the Chairman of the Board of Directors, at all
meetings of the Board of Directors, and shall have general supervision,
direction and control of the business of the corporation. 


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Except as the Board of Directors shall authorize the execution thereof in some
other manner, he shall execute bonds, mortgages and other contracts in behalf of
the corporation, and shall cause the seal to be affixed to any instrument
requiring it and when so affixed the seal shall be attested by the signature of
the Secretary or the Treasurer or an Assistant Secretary or an Assistant
Treasurer.

      Section 5. Vice President. Each Vice President shall have such powers and
shall perform such duties as shall be assigned to him by the directors.

      Section 6. Treasurer. The Treasurer shall have the custody of the
corporate funds and securities and shall keep full and accurate account of
receipts and disbursements in books belonging to the corporation. He shall
deposit all moneys and other valuables in the name and to the credit of the
corporation in such depositaries as may be designated by the Board of Directors.

      The Treasurer shall disburse the funds of the corporation as may be
ordered by the Board of Directors, or the President, taking proper vouchers for
such disbursements. He shall render to the President and Board of Directors at
the regular meetings of the Board of Directors, or whenever they may request it,
an account of all his transactions as Treasurer and of the financial 


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condition of the corporation. If required by the Board of Directors, he shall
give the corporation a bond for the faithful discharge of his duties in such
amount and with such surety as the Board of Directors shall prescribe.

      Section 7. Secretary. The Secretary shall give, or cause to be given,
notice of all meetings of stockholders and directors, and all other notices
required by law or by these By-Laws, and in case of his absence or refusal or
neglect so to do, any such notice may be given by any person thereunto directed
by the President, or by the directors, or stockholders, upon whose requisition
the meeting is called as provided in these By-Laws. He shall record all the
proceedings of the meetings of the corporation and of the directors in a book to
be kept for that purpose, and shall perform such other duties as may be assigned
to him by the directors or the President. He shall have the custody of the seal
of the corporation and shall affix the same to all instruments requiring it,
when authorized by the directors or the President, and attest the same.

      Section 8. Assistant Treasurers and Assistant Secretaries. Assistant
Treasurers and Assistant Secretaries, if any, shall be elected and shall have
such powers and shall perform such duties as shall be assigned to them,
respectively, by the directors.


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                                    ARTICLE V
                                  MISCELLANEOUS

      Section 1. Resignations. Any director, member of a committee or corporate
officer may, provided the same would not result in a breach of any contract to
which said person is a party, resign at any time. Such resignation shall be made
in writing, and shall take effect at the time specified therein, and if no time
be specified, at the time of its receipt by the President or Secretary. The
acceptance of a resignation shall not be necessary to make it effective.

      Section 2. Vacancies. If the office of any director, member of a committee
or corporate officer becomes vacant, by reason of death, disability or
otherwise, the remaining directors in office, though less than a quorum, by a
majority vote may appoint any qualified person to fill such vacancy, who shall
hold office for the unexpired term and until his successor shall be duly chosen.

      Section 3. Certificates of Stock. Certificates of stock, signed by the
Chairman of the Board of Directors, or the President or any Vice President, and
the Treasurer or an Assistant Treasurer, or Secretary to an Assistant Secretary,
shall be issued to each stockholder certifying the number of shares owned by him
in the corporation. When such certificates are countersigned (1) by a transfer
agent other than the corporation or its employee, or (2) by a registrar 


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other than the corporation or its employee, the signatures of such officers may
be facsimile.

      Section 4. Lost Certificates. A new certificate of stock may be issued in
the place of any certificate theretofore issued by the corporation, alleged to
have been lost or destroyed, and the directors may, in their discretion, require
the owner of the lost or destroyed certificate, or his legal representatives, to
give the corporation a bond, in such sum as they may direct, not exceeding
double the value of the stock represented by such certificate, to indemnify the
corporation against any claim that may be made against it on account of the
alleged loss of any such certificate, or the issuance of any such new
certificate.

      Section 5. Transfer of Shares. The shares of stock of the corporation
shall be transferable only upon its books by the holders thereof in person or by
their duly authorized attorneys or legal representatives, and upon such transfer
the old certificates shall be surrendered to the corporation by the delivery
thereof to the person in charge of the stock transfer books and ledgers, or to
such other person as the directors may designate, by whom they shall be
cancelled, and new certificates shall thereupon be issued. A record shall be
made of each transfer and whenever a transfer shall 


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be made for collateral security, and not absolutely, it shall be so expressed in
the entry of the transfer.

      Section 6. Stockholders Record Date. In order that the corporation may
determine the stockholders entitled to notice of or to vote at any meeting of
stockholders or any adjournment thereof, or to express consent to corporate
action in writing without a meeting, or entitled to receive payment of any
dividend or other distribution or allotment of any rights, or entitled to
exercise any rights in respect of any change, conversion or exchange of stock or
for the purpose of any other lawful action, the Board of Directors may fix, in
advance, a record date, which shall not be more than sixty nor less than ten
days before the date of such meeting, nor more than sixty days prior to any
other action. A determination of stockholders of record entitled to notice of or
to vote at a meeting of stockholders shall apply to any adjournment of the
meeting; provided, however, that the Board of Directors may fix a new record
date for the adjourned meeting.

      Section 7. Dividends. Subject to the provisions of the Certificate of
Incorporation, the Board of Directors may, out of funds legally available
therefor at any regular or special meeting, declare dividends upon the capital
stock of the corporation as and when they deem expedient. Before declaring any
dividend there may be set apart out of any 


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funds of the corporation available for dividends, such sum or sums as the
directors from time to time in their discretion deem proper for working capital
or as a reserve fund to meet contingencies or for equalizing dividends or for
such other purposes as the directors shall deem conducive to the interests of
the corporation.

      Section 8. Seal. The corporate seal shall be circular in form and shall
contain the name of the corporation, the year of its creation and the words
"CORPORATE SEAL DELAWARE." Said seal may be used by causing it or a facsimile
thereof to be impressed or affixed or otherwise reproduced.

      Section 9. Fiscal Year. The fiscal year of the corporation shall be
determined by resolution of the Board of Directors. In the absence of such
determination, the fiscal year shall be the year beginning June 1 and ending May
31.

      Section 10. Checks. All checks, drafts or other orders for the payment of
money, notes or other evidences of indebtedness issued in the name of the
corporation shall be signed by such officer or officers, agent or agents of the
corporation, and in such manner as shall be determined from time to time by
resolution of the Board of Directors.

      Section 11. Notice and Waiver of Notice. Whenever any notice is required
by these By-Laws to be given, personal 


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notice is not meant unless expressly so stated, and any notice so required shall
be deemed to be sufficient if given by depositing the same in the United States
mail, postage prepaid, addressed to the person entitled thereto at his address
as it appears on the records of the corporation, and such notice shall be deemed
to have been given on the day of such mailing. Stockholders not entitled to vote
shall not be entitled to receive notice of any meetings except as otherwise
provided by statute.

      Whenever any notice whatever is required to be given under the provisions
of any law, or under the provisions of the Certificate of Incorporation of the
corporation or these By-Laws, a waiver thereof in writing, signed by the person
or persons entitled to said notice, whether before or after the time stated
therein, shall be deemed equivalent thereto.

                                   ARTICLE VI
                                 INDEMNIFICATION

      To the full extent permitted by law, the corporation may indemnify any
person or his heirs, distributees, next of kin, successors, appointees,
executors, administrators, legal representatives and assigns 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 by reason of the 


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fact that he is or was a director, officer, employee or agent of the
corporation, or is or was serving at the request of the corporation as a
director, officer, employee or agent of another corporation, partnership, joint
venture, trust or other enterprise, domestic or foreign, against expenses,
attorneys' fees, court costs, judgments, fines, amounts paid in settlement and
other losses actually and reasonably incurred by him in connection with such
action, suit or proceeding.

                                   ARTICLE VII
                                   AMENDMENTS

      These By-Laws may be altered or repealed and By-Laws may be made at any
annual meeting of the stockholders or at any special meeting thereof by the
affirmative vote of a majority of the stock issued and outstanding and entitled
to vote thereat, or by the affirmative vote of a majority of the Board of
Directors, at any regular meeting of the Board of Directors, or at any special
meeting of the Board of Directors.

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