Chevron Corp. (CVX) and Abbott Laboratories (ABT) are marketing $8 billion in bond deals Thursday as they refinance short-term borrowings into long-term debt in demand by investors.

Chevron's $5 billion deal consists of three, five- and 10-year bonds that would in part refinance debt including commercial paper, short-term notes used to fund everyday needs like payroll and rent.

The company had $5.7 billion in commercial paper outstanding at the end of 2008 but much of that has been reclassified to long-term debt because of credit facilities that support its potential refinancing, according to a filing. After the reclassification, the company has $2.8 billion in short-term debt and $5.7 billion in long-term debt.

The new Chevron bonds will all come with a risk premium, or spread, of 195 basis points over comparable Treasury yields, according to the price talk.

Meanwhile, Abbott sold $3 billion of bonds maturing in 10 and 30 years. The health-care company said it would use the proceeds to repay about $1 billion in commercial paper and for other corporate purposes.

The $2 billion 10-year piece was sold at a risk premium of 220 basis points over Treasurys to yield 5.18%, and the $1 billion 30-year issue was sold at a spread of 235 basis points over Treasurys to yield 6.016%.

An existing 10-year note from Abbott due 2017 is trading at a spread of 202 basis points over Treasurys, according to MarketAxess.

These companies don't issue bonds as often as others, and so are of particular interest to investors looking to diversify their holdings. The last time Chevron issued debt was a $750 million deal in 2003; Abbott, a $3.5 billion deal in 2007, according to data provider Dealogic.

"New or less frequent high-quality issuers have generally been met with strong demand as investors seek to add new issuers to their portfolios," said Jon Duensing, principal at Smith Breeden Associates.

He expects issuance from high-quality issuers to continue given large refinancing needs, and that it will see good reception from investors.

"The companies that have accessed the market have been predominately stronger, better-capitalized businesses, with the wherewithal to handle an economic downturn," said Tim Compan, corporate bond portfolio manager at Cleveland-based Allegiant Asset Management. "There has, and will be indigestion as spreads tighten, but for the most part, new issues have been well-received."

February already ranks as the ninth-largest on record in issuance of U.S. dollar-denominated high-grade debt, according to Dealogic. The month's tally stands at $67 billion and for this week alone, $9 billion, in bonds not backed by the Federal Deposit Insurance Corp.

Energy and utility companies made up a majority of bonds sold this week, and more are on tap. Oneok Inc. (OKE), Alabama Power, and Williams Cos. (WMB) are also offering smaller deals that totaled $1.6 billion. Investors consider such companies as faring better than others, such as retailers, in the weakening economy.

Noble Energy Inc. (NBL) sold $1 billion of 10-year bonds that offered a risk premium of 550 basis points over Treasurys on Tuesday. The spread has since decreased to 500 basis points, indicating investor demand.

The corporate supply Thursday comes amid a glut of other debt. Fannie Mae (FNM) sold a record $15 billion in two-year notes, which went on to trade well in the so-called secondary market. There was also an auction of $22 billion in seven-year Treasury notes Thursday afternoon.

-By Romy Varghese, Dow Jones Newswires; 215-656-8263; romy.varghese@dowjones.com

(Kate Haywood contributed to this report.)