The phrase "a reliable part" is correct and usable in written English.
It can be used to describe a component or element that is dependable or trustworthy in a particular context, such as machinery, software, or a team.
Example: "In our project, having a reliable part is crucial to ensure everything functions smoothly."
Alternatives: "a dependable component" or "a trustworthy element."
Defensemen Scott Stevens and Ken Daneyko, whose combined 37 N.H.L. seasons make them a reliable part of the furniture.
The elderly were once a reliable part of the Democratic coalition, but opinion polls suggest that Republicans won a majority of their votes in the last three House elections.
But since Hollywood's studio leadership has always been a reliable part of the pro-Clinton phalanx, you won't be seeing much of the Starr report on the silver screen.
Catholics were a reliable part of the urban, New Deal coalition for many years but trended Republican in the 1970s and 1980s, becoming an important element of the so-called Reagan Democrats.
The spirit of Henry Clay and the nationalist Whigs died, and Democratic Kentucky, despite occasional internal differences over matters of railroad development and mining, became a reliable part of the Solid South.
The bassist Mark Helias has been a reliable part of a lot of groups around New York for the last few decades, but his own trio is the best setting in which to hear him, as it engages his compositional sense as well as his convincing bounce.
A more reliable part of the proposed policy is the adoption of a relative cutoff point of 15%% of the extracted terms.
In another sign Mr. Obama is looking toward the general election, he's reaching out to Jewish voters — a typically reliable part of the Democratic base.
Whether black theatergoers become a larger, reliable part of the Broadway audience remains to be seen, as do the range and quality of the shows that are offered to appeal to them.
And it's an equally reliable part of this quadrennial trajectory that, once the action starts, all the disasters are forgotten.
It's plain that older Americans have become a more important and reliable part of the audience that goes to movie theatres.
