301 GB/T 3103.2-1982 紧固件公差 用于精密机械的螺栓、螺钉和螺母 Tolerances for fasteners--Bolts, screws and nuts for fine mechanics
302 GB/T 3103.3-1982 紧固件公差 平垫圈 Tolerances for fasteners--Washers
303 GB/T 3103.4-1992 紧固件公差 耐热用螺纹连接副 Tolerances for fasteners--Components for bolted connections made mainly from materials with a high temperature strength
304 GB/T 3104-1982 紧固件 六角产品的对边宽度 Fasteners--Widths across flats of hexagon products
305 GB/T 3105-1982 螺栓和螺钉的头下圆角半径 Radii under the head of bolts and screws
306 GB/T 3106-1982 螺栓、螺钉和螺柱的公称长度和普通螺栓的螺纹长度 Bolts, screws and studs--Nominal lengths, and thread lengths for general purpose bolts
307 GB/T 3162-1991 滑动轴承薄壁轴瓦尺寸、结构要素与公差 Plain bearings—Thin-walled bearing shells—Dimensions, structure elements and tolerances
308 GB/T 3287-1982 可锻铸铁管路连接件技术条件 Technical requirements of malleable cast iron pipe fittings
309 GB/T 3288-1982 可锻铸铁管路连接件验收规则 Delivery requirements of malleable cast iron pipe fittings
310 GB/T 3289.1-1982 可锻铸铁管路连接件型式尺寸 管件结构尺寸表 Malleable cast iron pipe fittings--Type size--Dimensions list of pipe fittings structure
311 GB/T 3289.2-1982 可锻铸铁管路连接件型式尺寸 弯头 内外丝弯头 Malleable cast iron pipe fittings--Type size--Elbows male and female elbows
312 GB/T 3289.3-1982 可锻铸铁管路连接件型式尺寸 45°弯头 45°内外丝弯头 Malleable cast iron pipe fittings--Type size--Elbows 45°, male and female elbows 45°
313 GB/T 3289.4-1982 可锻铸铁管路连接件型式尺寸 异径弯头 Malleable cast iron pipe fittings--Type size--Reducing elbows
314 GB/T 3289.5-1982 可锻铸铁管路连接件型式尺寸 异径内外丝弯头 Malleable cast iron pipe fittings--Type size--Male and female reducing elbows
315 GB/T 3289.6-1982 可锻铸铁管路连接件型式尺寸 侧孔弯头 Malleable cast iron pipe fittings--Type size--Side outlet elbows
316 GB/T 3289.7-1982 可锻铸铁管路连接件型式尺寸 月弯 内外丝月弯 外丝月弯 Malleable cast iron pipe fittings--Type size--Return bends, male and female return bends, thread return bends
317 GB/T 3289.8-1982 可锻铸铁管路连接件型式尺寸 45°月弯45°内外丝月弯45°外丝月弯 Malleable cast iron pipe fittings--Type size--Long sweep bends 45°，male and female long sweep bends 45°,male long sweep bends 45°
318 GB/T 3289.9-1982 可锻铸铁管路连接件型式尺寸 U型弯头 Malleable cast iron pipe fittings--Type size--U-Elbows(return bends)
319 GB/T 3289.10-1982 可锻铸铁管路连接件型式尺寸 三通 内外丝三通 Malleable cast iron pipe fittings--Type size--Tees, male and female tees
320 GB/T 3289.11-1982 可锻铸铁管路连接件型式尺寸 异径内外丝三通 Malleable cast iron pipe fittings--Type size--Male and female reducing tees
321 GB/T 3289.12-1982 可锻铸铁管路连接件型式尺寸 中大异径三通 Malleable cast iron pipe fittings--Type size--Medium-large reducing tees [tees(increasing on the branch)]
322 GB/T 3289.13-1982 可锻铸铁管路连接件型式尺寸 侧大异径三通 Malleable cast iron pipe fittings--Type size--Lateral-large reducing tees
323 GB/T 3289.14-1982 可锻铸铁管路连接件型式尺寸 中小异径三通 Malleable cast iron pipe fittings--Type size--Medium-less reducing tees
324 GB/T 3289.15-1982 可锻铸铁管路连接件型式尺寸 侧小异径三通 Malleable cast iron pipe fittings--Type size--Lateral-less reducing tees
325 GB/T 3289.16-1982 可锻铸铁管路连接件型式尺寸 中小偏心异径三通 Malleable cast iron pipe fittings--Type size--Medium-less eccentric reducing tees
326 GB/T 3289.17-1982 可锻铸铁管路连接件型式尺寸 45°三通 Y型三通 Malleable cast iron pipe fittings--Type size--Tees45°, Y pieces(tees)
327 GB/T 3289.18-1982 可锻铸铁管路连接件型式尺寸 Y型异径三通 Malleable cast iron pipe fittings--Type size--Y Piece reducing(tees)
328 GB/T 3289.19-1982 可锻铸铁管路连接件型式尺寸 侧孔三通 Malleable cast iron pipe fittings--Type size--Side outlet tees
329 GB/T 3289.20-1982 可锻铸铁管路连接件型式尺寸 四通 Malleable cast iron pipe fittings--Type size--Crosses
330 GB/T 3289.21-1982 可锻铸铁管路连接件型式尺寸 异径四通 Malleable cast iron pipe fittings--Type size--Reducing crosses
331 GB/T 3289.22-1982 可锻铸铁管路连接件型式尺寸 外接头 内外丝接头 Malleable cast iron pipe fittings--Type size--Male joints(sockets), male and female joints (sockets)
332 GB/T 3289.23-1982 可锻铸铁管路连接件型式尺寸 无方内接头 Malleable cast iron pipe fittings--Type size--No-square inner joint (nipples)
333 GB/T 3289.24-1982 可锻铸铁管路连接件型式尺寸 异径外接头 Malleable cast iron pipe fittings--Type size--Reducing male joints (sockets)
334 GB/T 3289.25-1982 可锻铸铁管路连接件型式尺寸 偏心异径外接头 Malleable cast iron pipe fittings--Type size--Eccentric reducing male joints (sockets)
335 GB/T 3289.26-1982 可锻铸铁管路连接件型式尺寸 内接头 Malleable cast iron pipe fittings--Type size--Inner joints (nipples hexagon)
336 GB/T 3289.27-1982 可锻铸铁管路连接件型式尺寸 异径内接头 Malleable cast iron pipe fittings--Type size--Reducing inner joints(nipples hexagon)
337 GB/T 3289.28-1982 可锻铸铁管路连接件型式尺寸 内外螺丝 Malleable cast iron pipe fittings--Type size--Male and female screws (bushings)
338 GB/T 3289.29-1982 可锻铸铁管路连接件型式尺寸 通丝外接头 Malleable cast iron pipe fittings--Type size--Through thread male joint (sockets)
339 GB/T 3289.30-1982 可锻铸铁管路连接件型式尺寸 锁紧螺母 Malleable cast iron pipe fittings--Type size--Backnuts
340 GB/T 3289.31-1982 可锻铸铁管路连接件型式尺寸 外方管堵 Malleable cast iron pipe fittings--Type size--Outer-square plugs

341 GB/T 3289.32-1982 可锻铸铁管路连接件型式尺寸 带边外方管堵 Malleable cast iron pipe fittings--Type size--Outer-square beaded plugs
342 GB/T 3289.33-1982 可锻铸铁管路连接件型式尺寸 内方管堵 Malleable cast iron pipe fittings--Type size--Inner-square plugs
343 GB/T 3289.34-1982 可锻铸铁管路连接件型式尺寸 管帽 Malleable cast iron pipe fittings--Type size--Tube caps (caps plugs)
344 GB/T 3289.35-1982 可锻铸铁管路连接件型式尺寸 活接弯头 内外丝活接弯头 Malleable cast iron pipe fittings--Type size--Union elbows, male and female union elbows
345 GB/T 3289.36-1982 可锻铸铁管路连接件型式尺寸 活接三通 Malleable cast iron pipe fittings--Type size--Union tees
346 GB/T 3289.37-1982 可锻铸铁管路连接件型式尺寸 平形活接头 Malleable cast iron pipe fittings--Type size--Parallel unions
347 GB/T 3289.38-1982 可锻铸铁管路连接件型式尺寸 锥形活接头 Malleable cast iron pipe fittings--Type size--Taper unions
348 GB/T 3289.39-1982 可锻铸铁管路连接件型式尺寸 平形活接头垫圈 Malleable cast iron pipe fittings--Type size--Parallel union gaskets
349 GB/T 3374-1992 齿轮基本术语 Basic terminology of gears
350 GB/T 3478.1-1995 圆柱直齿渐开线花键模数 基本齿廓 公差 Straight cylindrical involute splines--Modules, basic rack profiles and tolerances