Why China refuses to play its 'Soviet card'

China's relations with the Soviet Union are likely to remain adversarial for a long time to come, official Chinese sources say.

These sources, who are familiar with the course of Sino-Soviet talks since 1970, see no signs that Moscow is prepared to abandon ''hegemonism,'' Peking's code word for Soviet expansionism.

Western diplomats here believe that even if China succeeds eventually in normalizing relations with the Soviet Union, relations between the two huge communist neighbors are not likely to be much friendlier than those between Washington and Moscow.

Western newspapers have been full of speculation as to whether China was playing a ''Soviet card'' against the United States, much as they speculated in an earlier period that Washington was playing a ''China card'' against the Soviet Union.

But the Chinese insist that Sino-Soviet relations and Sino-American relations are two entirely separate categories. Western diplomats tend to agree with them.

After all, the United States and the Soviet Union confront each other in nearly every important part of the globe. Yet many American farmers depend heavily on Soviet grain purchases to keep them solvent. Washington and Moscow are in constant communication with each other over a host of subjects from trade and cultural exchanges to routine subjects such as how their warships should behave when they encounter each other at sea.

China has very little of this kind of contact with Moscow. A few Soviet athletes have competed in China this year. But there are no Soviet students here , nor any Chinese students in the Soviet Union. (There are some 8,000 Chinese students in the US.)

As for trade, one Chinese source pointed out that last year Sino-American trade reached $5.2 billion while Sino-Soviet trade was $300 million.

Deng Xiaoping, China's top leader, and his colleagues have repeatedly pointed out that from Peking's viewpoint, three principal obstacles prevent normalization of Sino-Soviet relations.

The first is the presence, in Deng's words, of ''1 million Soviet troops'' along the border between China and the Soviet Union, which includes Mongolia.

The second is Soviet support for the Vietnamese occupation of Kampuchea.

The third is the Soviet invasion and occupation of Afghanistan.

China insists on the removal of these obstacles, a Chinese official said, because they feature Soviet actions taking place all around China's periphery. Therefore they constitute a direct threat to China's security as well as a threat to peace in Asia.

The official indicated that the most pressing of these three problems from China's viewpoint is Kampuchea, because fighting is going on there right now, whereas the Sino-Soviet and Sino-Mongol borders are calm. (It is estimated that the Soviets have 50 divisions along the Sino-Soviet border plus 45,000 men in Mongolia.)

China used to accuse the Soviet Union of ''social imperialism,'' one official said. Today it speaks only of ''hegemonism,'' but according to this official, the meaning has not been lost.

Peking does not expect the Soviet Union to abandon ''hegemonism'' in the near future. Therefore Sino-Soviet talks are likely to go on for a long time just as Soviet-American talks over disarmament have gone on for a long time.

Still, the official thought, it's possible to force the Soviet Union to change its tactics on certain specific issues, even though overall its policies remain hegemonistic. He did not spell out what these specific issues might be. As for Sino-American relations, the official said that strategic cooperation remains alive but that sovereignty and the principle of peaceful coexistence take precedence. Taiwan, he indicated, remains the major problem between Peking and Washington, for this is an issue that involves sovereignty.

Sino-Soviet talks have been going on intermittently for 12 years. The latest round began in the Chinese capital Oct. 5 with Soviet Deputy Foreign Minister Leonid Ilyichov and Chinese Deputy Foreign Minister Qian Qichen.

The talks ended Oct. 21 and Ilyichov flew back to Moscow Oct 29. The next round will be held in Moscow, but the date has not yet been fixed.