SCHEDULE 13G 
 
Amendment No. 2 
Quanex Corporation 
common stock 
Cusip # 747620102 
Filing Fee: No 


Cusip # 747620102 
Item 1:	Reporting Person - FMR Corp. - (Tax ID:  04-2507163) 
Item 4:	Commonwealth of Massachusetts 
Item 5:	77,629 
Item 6:	None 
Item 7:	1,463,729 
Item 8:	None 
Item 9:	1,463,729 
Item 11:	10.96% 
Item 12:	HC  
 
 


Cusip # 747620102 
Item 1:	Reporting Person - Edward C. Johnson 3d - (Tax ID:  ###-##-####) 
Item 4:	United States of America 
Item 5:	None 
Item 6:	None 
Item 7:	1,463,729 
Item 8:	None 
Item 9:	1,463,729 
Item 11:	10.96% 
Item 12:	IN  
 
 


SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS 
FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b) 
 
 
Item 1(a).	Name of Issuer: 
 
		Quanex Corporation 
 
Item 1(b).	Name of Issuer's Principal Executive Offices: 
 
		1900 West Loop South, Suite 1500 
		Houston, TX  77027-2186 
 
Item 2(a).	Name of Person Filing:  
 
		FMR Corp. 
 
Item 2(b).	Address or Principal Business Office or, if None, Residence: 
 
		82 Devonshire Street, Boston, Massachusetts  02109 
 
Item 2(c).	Citizenship: 
 
		Not applicable 
 
Item 2(d).	Title of Class of Securities: 
 
		Common Stock 
 
Item 2(e).	CUSIP Number:   
 
		747620102 
 
Item 3.	This statement is filed pursuant to Rule 13d-1(b) or 13d-2(b) and the 
person filing, FMR Corp., is a parent holding company in accordance 
with Section 240.13d-1(b)(ii)(G).  (Note:  See Item 7). 
 
Item 4.	Ownership 
 
	(a)	Amount Beneficially Owned:
	1,463,729 
 
	(b)	Percent of Class:
	10.96% 
 
	(c)	Number of shares as to which such person has:   
 
	(i)	sole power to vote or to direct the vote:
	77,629 
 
	(ii)	shared power to vote or to direct the vote:
	None 
 
	(iii)	sole power to dispose or to direct the disposition of:
	1,463,729 
 
	(iv)	shared power to dispose or to direct the disposition of:
	None 
 
 


Item 5.	Ownership of Five Percent or Less of a Class. 
 
	Not applicable. 
 
Item 6.	Ownership of More than Five Percent on Behalf of Another Person. 
 
	Various persons have the right to receive or the power to 
direct the receipt of dividends from, or the proceeds from the 
sale of, the common stock of Quanex Corporation.  The interest 
of one person, Fidelity Magellan Fund, an investment company 
registered under the Investment Company Act of 1940, in the 
common stock of Quanex Corporation, amounted to 1,183,600 
shares or 8.86% of the total outstanding common stock at 
October 31, 1994.   
 
Item 7.	Identification and Classification of the Subsidiary Which Acquired 
the Security Being Reported on By the Parent Holding Company. 
 
	See attached Exhibit(s) A and B. 
 
Item 8.	Identification and Classification of Members of the Group. 
 
	Not applicable, see attached Exhibit A.  
 
Item 9.	Notice of Dissolution of Group. 
 
	Not applicable. 


Item 10.	Certification. 
 
	By signing below I certify that, to the best of my knowledge 
and belief, the securities referred to above were acquired in 
the ordinary course of business and were not acquired for the 
purpose of and do not have the effect of changing or 
influencing the control of the issuer of such securities and 
were not acquired in connection with or as a participant in any 
transaction having such purpose or effect. 
 
 
Signature 
 
	After reasonable inquiry and to the best of my knowledge and 
belief, I certify that the information set forth in this 
Schedule 13G in connection with FMR Corp's beneficial ownership 
of the common stock of Quanex Corporation at October 31, 1994 
is true, complete and correct.  
 
 
 
	November 9, 1994	 
Date 
 
 
 
	/s/Arthur S. Loring 
Signature 
 
 
 
	Arthur S. Loring, Vice 
President	 
Name/Title 
 
 


SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS 
FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b) 
 
	Pursuant to the instructions in Item 7 of Schedule 13G, Fidelity 
Management & Research Company ("Fidelity"), 82 Devonshire Street, Boston, 
Massachusetts 02109, a wholly-owned subsidiary of FMR Corp. and an investment 
adviser registered under Section 203 of the Investment Advisers Act of 1940, 
is the beneficial owner of 1,371,900 shares or 10.27% of the common stock 
outstanding of Quanex Corporation ("the Company") as a result of acting as 
investment adviser to several investment companies registered under Section 8 
of the Investment Company Act of 1940.   
 
	The ownership of one investment company, Fidelity Magellan Fund, amounted 
to 1,183,600 shares or 8.86% of the common stock outstanding.  Fidelity 
Magellan Fund has its principal business office at 82 Devonshire Street, 
Boston, Massachusetts 02109.   
 
	Edward C. Johnson 3d, FMR Corp., through its control of Fidelity, and the 
Funds each has sole power to dispose of the 1,371,900 shares owned by the 
Funds. 
 
	Neither FMR Corp. nor Edward C. Johnson 3d, Chairman of FMR Corp., has 
the sole power to vote or direct the voting of the shares owned directly by 
the Fidelity Funds, which power resides with the Funds' Boards of Trustees.  
Fidelity carries out the voting of the shares under written guidelines 
established by the Funds' Boards of Trustees. 
 
	Fidelity Management Trust Company, 82 Devonshire Street, Boston, 
Massachusetts 02109, a wholly-owned subsidiary of FMR Corp. and a bank as 
defined in Section 3(a)(6) of the Securities Exchange Act of 1934, is the 
beneficial owner of 91,829 shares or 0.69% of the common stock outstanding of 
the company as a result of its serving as investment manager of the 
institutional account(s).  The number of shares of common stock of Quanex 
Corporation owned by the institutional account(s) at October 31, 1994 included 
1,429 shares of common stock resulting from the assumed conversion of 1,800 
shares of the Convertible Preferred (0.794 shares of common stock for each 
share of the Convertible Preferred). 
 
	FMR Corp., through its control of Fidelity Management Trust Company, has 
sole dispositive power over 91,829 shares and sole power to vote or to direct 
the voting of 77,629 shares, and no power to vote or to direct the voting of 
14,200 Shares of common stock owned by the institutional account(s) as 
reported above. 
 
	Edward C. Johnson 3d owns 24.9% of the outstanding voting common stock of 
FMR Corp.  Mr. Johnson 3d is Chairman of FMR Corp.  Various Johnson family 
members and trusts for the benefit of Johnson family members own FMR Corp. 
voting common stock.  These Johnson family members, through their ownership of 
voting common stock and the execution of a family shareholders' voting 
agreement, form a controlling group with respect to FMR Corp. 
 


SCHEDULE 13G - TO BE INCLUDED IN STATEMENTS 
FILED PURSUANT TO RULE 13d-1(b) or 13d-2(b) 
 
RULE 13d-1(e)  AGREEMENT 
 
	The undersigned persons, on November 9, 1994, agree and consent to the 
joint filing on their behalf of this Schedule 13G in connection with their 
beneficial ownership of the common stock of Quanex Corporation at October 31, 
1994. 
 
	FMR Corp. 
	By	/s/Arthur S. Loring 
Arthur S. Loring
Vice President - Legal 
		Edward C. Johnson 3d 
	By	/s/Arthur S. Loring 
Arthur S. Loring
Under Power of Attorney dated 
5/17/89
On File with Schedule 13G for
Airborne Freight Corp. 9/10/91 
	Fidelity Management & Research Company 
	By	/s/Arthur S. Loring 
Arthur S. Loring
Sr. V.P. and General Counsel 
	Fidelity Magellan Fund 
	By	/s/Arthur S. Loring 
Arthur S. Loring
Secretary