Ashraf Ghorbal, the Egyptian ambassador, had planned this week as a vacation. But instead of sun and surf, he's got Sadat, Begin and Carter. Moreover, he's at the helm of an embassy where the phones haven't stopped ringing for a week, where the teletype machines provide a clackety Muzak and where laughter is embroidered with a frantic note.

"This place," says Ambassador Ghorbal, excusing himself for a brief, clipped discussion with a colleague in Arabic, "this place is a beehive." Around him is the controlled chaos that has characterized the embassy since peace with Israel was announced shy of two weeks ago.

For one thing, as a staff man noted, the invitations to the signing are just about the hottest commodity in town with thousands of requests.

The embassy officer who is over- seeing protocol for President Anwar Sadat's arrival tomorrow and the ceremonies surrounding the treatysigning on Monday tries to describe the treadmill of diplomatic decisions. He sighs, and says: "Everything has to be tackled at once." And the press counselor, chomping on a cigar and finishing up plans for the Egyptian press and a group he calls "Cronkite, Chancellor and Barbara," explains: "We are up in arms."

Another meeting is over. The ambassador, a short, balding man who wears tinted glasses and an impeccable gray atriped suit, shoots a no-nonsense look toward his staff. Regrets are not the style of a school diplomat. "I have given up my vacation for history," says Ghorbal. "I'm gratified I'm here at this glorious moment."

No one actually looks nervous at the Egyptian embassy but they all do looked consumed with anxiety. a secretary picks up a phone, answers a greeting with "Good morning? What's good about it?" There's an almost palpable tension, like a cigareette- clouded study hall the night before a final examination.

Details needing attention:

the preparation of the ambassador's residence for President Sadat.

the vacating by the ambassador and his family.

polite thank-yous and refusals of 15 offers of honorary degrees for Sadat next week.

negotiations with A.T.&T. and COMSAT for satellite time so Egyptian television can receive the treaty- signing live.

the treaty itself -- its language to be verified in Arabic, Hebrew and English.

Ambassador Ghorbal looks amused, he's a pro and he knows he sounds too casual: "This week of 14-hour days is all for a cause. Once President Carter returned to Egypt, things were in gear. It passed the point of no return. The only tension is working against the clock."

Ever since Ghorbal, a Garvard-educated political scientist, was first assigned to Washington in the late 1960s he has found himself in strained situations. First he was an ambassador without credentials. For five years he worked at the Indian embassy because Egypt and the United States had no diplomatic relations. But he was always outspoken, always offering the scholarly explanation, always requesting equal treatment in a country where the pro-Israeli interests were well-or- ganized. Two years ago he made international news as one of three ambassadors who negotiated with armed Hanafi Muslims who were holding 124 hostages in three downtown Washington buildings.

In the six days Ambassador Ghorbal has been back from Cairo, he says, his schedule has been hectic but not crisis- ridden. The staff meetings, sometimes twice a day, have gone smoothly. His five-bedroom residence has received a spring cleaning and freshcut flowers for every room. The refrigerator was not stocked. "The president is on a very strict diet. He eats only one meal a day and very little, maybe some soup at lunch," says Amal Ghorbal, the ambassador's wife. The Sadats are bringing their four children.

The only really uneasy moment in the past week, recalls Ambassador Ghorbal, was when the phones started ringing with the angry reaction of Arab ambassadors to Israeli Prime Minister Begin's Knesset speech. "I know words are used for internal consumption. But it made Wednesday very tedious," says Ghorbal. "The ambassadors were saying how do you reconcile with Prime Minister Begin. I had warned my colleagues against Begin's statements, told them to 'watch about your blood pressure.'" He sips coffee, smiling.

"I can't get tense, then I wouldn't be able to think straight. Then everyone else will go haywire," says the ambassador, in his broad accents."On Monday I will be a joyful and happy participant, one man among the delegation."

Perhaps the cool mood of the Egyptian embassy is the result of practice. President Sadat has visited Washington five times in three years. "There are no contradictions in the embassy's views and the views of the staff in Cairo about how the visit should go," says Bedair El Ghamrawy, the first secretary, who has responsibility for protocol and security.

"We consider this a peace visit and are concentrating only on events that reflect on the treaty and normalization," says Ghamrawy. All invitations outside Washington, all honorary degrees were refused. The last 10 days have been spent juggling Sadat's schedule -- where he should go, whom he should meet. "On every visit we are careful about our contacts with Congress," says Ghamrawy, and adds that Tuesday night's dinner with the U.S. Chamber of Commerce was scheduled "because economic development, normalization and peace" are interrelated. Then there are the schedule arrangements for Sadat.

What has overwhelmed the staff has been the number of requests for invitations to the treaty-signing. "The numbers are fantastic, in the thousands.There are people who call, people who send telegrams, peopld who come by," says Ghamrawy, breaking from his diplomat's reserve to marvel. But then, the diplomat's answer. "We tell them we do what we can but the final decision is up to the White House."

"Hey, I talked to them yesterday (a big network) and told them, one photo opportunity in the beginning, then leave them in peace," says press counselor Mohammed Hakki. He loves the whirlwind of the Mideast negotiations, the pace, the surprises, the tensions since President Sadat went to Jerusalem in 1977.

"Who doesn't think they should have 10 minutes of President Sadat's time?" Hakki waves the air, waiting until the sould of a copying machine coughing in overtime dies down. In his office in one of the two well-worn buildings of the embassy, there's a painting and a sculpture people have sent as presents for the Sadats. "Then there are these groups, the Egyptian students, the businessmen, the leaders of the Jewish Community, leaders of the Christian community, the writers, the television interviewers." And Hakki has divided the journalists into "one-on-one, talk shows, out-of-town, European and Canadian."

"The real problem with Sadat is time," says Kakki unnecessarily. The journalists have to come after people like U.N. Secretary General Kurt Waldheim and World Bank President Robert McNamara. Hakki, a journalist for 30 years. also has to handle 50 representatives of Egyptian newspapers and magazines. "There's Amina Lel Said, a feminist, an old horse and old fighter, sharp and witty. And Avis Mansour, who's a voracious reader. We will go right to Sidney Kramer's and Saville's and he will probably spend $1,000."

He doesn't expect any surprises, such as two weeks ago when President Carter decided to return to Cairo and Hakki had hundreds of journalists and no telexes at the airport. "There's Carter saying we have done it and I have seven busloads of journalists who have two hours to file their story."

A friend calls, asking Hakki if he has time for lunch. A long laugh follows as Hakki holds the mouthpiece four to six inches away. "Well, I'm almost mummified with ribbons of problems," he says. Another time, "We are trying to keep all the focus on the historical importance of the visit, no excesses," he says. "And Sadat agrees, he says this is Jimmy Carter's show, this is peace, peace above all."

One problem hasn't been solved yet. A class at Longfellow Elementary School, Oak Park, Ill., voted that President Sadat would enjoy that," says the ambassador's secretary. "Now it's a matter of where the schedule has a break."