When the Philadelphia Flyers skate onto the ice at Hersheypark Arena Friday night, it will be difficult for Bob Kelly to refrain from joining them. For Dennis Ververgaert self control will be required to endure the wait for the opening faceoff and the opportunity to alter a few derogatory opinions.

Kelly was a Flyer for 10 years before he was dealt to Washington in August, ostensibily to make room for younger talent. In all that time, Kelly rarely skated a regular shift, but was largely a spot player with the assignment of injecting some spark into a dull performance.

Ververgeart wore the orange, black and white only 1 1/2 seasons before he was handed his free agency June 1 and he is here in the Capitals training camp on a trial basis, although he seems destined to received a contract before the season opener Oct. 10.

In each case this will be the first chance to show the Flyers general manager, Keith Allen, that Capital gains were Flyer losses.

"I don't think it will be too bad here in Hershey; it will be worse the first time I go into Philly," Kelly said. "You can't forget 10 years of wearing the jersey. But I've got to try to put that in the past. Right now I'm looking forward to Capital Centre and Washington.

"I appreciate the chance to play regularly with two capable hockey players like Dennis (Maruk) and Prony (Jean Pronovost). But whatever role Gary Green gives me is fine with me. I had a lot of roles in Philly and I never complained about any of them."

Ververgaret did not protest the way he was utilized in Philadelphia, but never understood it, either. He could play well, as he did the night he scored twice against Washington, and still find himself in the press box watching the next game.

"As soon as Pat Quinn got there, I was sitting out and I was starting to think to myself, 'What happened?" Ververgaert said "I don't like to make a fuss and I never did all year. I just didn't know why. They didn't give me a reason. They just talked a lot and never really siad anything.

"It was a funny feeling. If there was an injury they'd bring up another right wing. They had six right wings at one time and then they put Bob Kelly at right wing occasionally. I thought I was doing okay when I got the chance, but I guess they didn't."

Ververgaret had been offered a contract by Philadelphia at the start of the 1979-80 season, but elected to play out his option instead, figuring "I could prove myself over a full year better than over half a year."

The strategy failed, because not only did he not receive the chance to prove himself, he was severed completely on June 1.

"I was kind of shocked to be just cut loose and I couldn't understand it," Ververgaert said. "Then a lot of clubs said they had too many players and I couldn't catch on. I thought I could have helped a lot of clubs, but now I'm in Washington.

"Things are progressing better every day and I'm feeling good. I wasn't really happy coming just on a trial, but I worked hard all summer and I felt confident in myself. I think things look good for the season."

Both Green and General Manager Max McNab have expressed unsolicited satisfaction with Ververgaert and it seems certain, barring a mediocre effort this weekend, that he will be signed by the Capitals. Certainly there will be no lack of effort on his part Friday.

"Bob and I are ready for them, ready to show them they made a mistake," Ververgaert said. "Washington hasn't got a good record against them and we want to change that."

The 7:30 exhibition in 7,286-seat Hersheypark Arena is sold out, although the Flyers will be leaving Bobby Clarke, Bill Barber, Reg Leach and Ken Linseman, who is out 6 1/2 weeks with a broken leg, at home.

With three games in three nights coming up, the Capitals will substitue Tim Tookey for Rolf Edberg, Wes Jarvis for Guy Charron and Howard Walker for Ivan Labre. Wayne Stepheson, another ex-Flyer, will be in goal, leaving Mike Palmateer to play Saturday in Toronto.

The Capitals assigned five players to Port Huron, Mich., of the International League today. Shipped out were goalie Bart Hunter, defensemen Dan Haskins and John Haddad, and forwards Steve Blue and Mark Green. . . The team's hardest shot may belong to goalie Palmateer. Trying to shoot a puck through the small hole in front of the scorer's table, Palmateer foiled Gary Green in a postpractice shootout and the team counted in cadence while the coach performed the required 10 pushups. Palmateer proved so tough on Paul Mulvey in another drill, taking penalty shots until one was successful, that Rick Green lay on the ice laughing. The entire team applauded when Mulvey, after about 15 attempts, finally succeeded . . . Jarvis, bothered by a bruised kidney, resumed contact drills today . . . Paul MacKinnon missed practice to attend a friend's funeral in his hometown of Brantford, Ontario.