Design:

This range of products is designed to overcome the problems of ‘O’-Ring extrusion when the system pressures are greater than the sealing capabilities of an unsupported ‘O’-Ring. The use of P.T.F.E. for anti-extrusion rings has many advantages over ‘hard rubber’ materials, particularly at high system pressures. The cold flow characteristics of PTFE are used to full advantage in reducing the extrusion gaps to a minimum and allowing automatic compensation for wear. The capability of specialist compounding to suit extremes of duty combined with a high resistance to virtually all chemicals, low friction and wear rates render PTFE as the ideal material for anti-extrusion devices.

 

Spiral

The spiral back up ring is the most common style in use being effectively self adjusting to diametral tolerances. Spiral back up rings are manufactured from virgin PTFE only.

Manufactured to suit O-Rings to BS1806, BS4518, JISB2401, JW17000, MS28782 standards Order as part number shown on table.e.g. BS 210 or as below…

BS1806 … BS006                                    JISB2401 … JISP003

BS4518 … BS0031-16                             JW17000 … SJWI7001 MS28782 … MS28782-001

Endless

The endless back up ring is used where problems can occur with the rotation of a screwed endcaps which on assembly could cause a spiral type to unwind. Endless back up rings are normally manufactured from virgin PTFE.

Manufactured to suit O-Rings to BS1806, BS4518, JISB2401, MS27595 standards.

 

Order as part number shown on the table with suffix E, e.g. BS 210/E or as below…

BS1806 … BS006/E                                BS4518 … BS0031-16/E

JISB2401… JISP003/E                            MS27595 … MS27595-004

The endless split back up ring is manufactured as the endless style but is split at 30^o to facilitate ease of assembly in certain applications. Endless split back up rings are normally manufactured from virgin PTFE.Endless Split

Manufactured to suit O-Rings to BS1806, BS4518, JISB2401, MS28774, AS8791/1 standards. Order as part number shown on the table with the suffix ES, e.g. BS 210/ES or as below…

BS1806 … BS006/ES                             BS4518 … BS0031-16/ES

JISB2401 … JISP003/ES                        MS28774 … MS28774-004/ES AS8791/1 … M8791-004/ES

How to order:

All the above can be supplied in a variety of PTFE materials including Virgin PTFE, Glass Filled PTFE and material specifications to MIL-R-8791/1.

The Endless and Endless Split Styles can also be supplied in Acetal, Nylon and Peek materials along with a variety of other filled PTFE grades such as Carbon and Bronze.

 

Housing:

For surface finish and recommended lead in chamfers refer to the illustration below. For housing dimensions and machining

tolerances refer to the catalogue page of selected seal. Refer to appendix 4 for value of tolerance symbols.

Fitting:

For the back up ring to function correctly, it is important that care be taken in fitting the backup within its housing.
For a detailed checklist, refer to Appendix 3.

 

Operating conditions:

Housing groove dimensions for ‘O’-Rings to BS1806 and BS4518 fitted with back-up rings in Dynamic and Static diametral applications.

Tables 1 & 2 refer to the housing drawings.

IMPERIAL
Housing groove dimensions for O-Rings to BS1806 fitted with back-up rings in Dynamic & Static diametrical applications.
O-Ring Section	Radial Width ‘S’		Groove Width L1				Radius ‘R1’ Max.	Cham. ‘C’ Min.
			One back-up ring		Two back-up rings
	Max.	Min.	Max.	Min.	Max.	Min.
0.070″	0.062″	0.060″	0.152″	0.147″	0.210″	0.205″	0.030″	0.085″
0.103″	0.094″	0.091″	0.199″	0.194″	0.257″	0.252″	0.030″	0.097″
0.139″	0.125″	0.122″	0.247″	0.241″	0.305″	0.299″	0.030″	0.103″
0.210″	0.188″	0.184″	0.355″	0.348″	0.427″	0.420″	0.030″	0.156″
0.275″	0.250″	0.245″	0.480″	0.473″	0.582″	0.576″	0.030″	0.187″

Table 1

METRIC
Housing groove dimensions for O-Rings to BS4518 fitted with back-up rings in Dynamic & Static diametrical applications.
O-Ring Section	Radial Width ‘S’		Groove Width L1				Radius ‘R1’ Max.	Chamf. ‘C’ Min.
			One back-up ring		Two back-up rings
	Max.	Min.	Max.	Min.	Max.	Min.
1.6 mm	1.3 mm	1.25 mm	4.0 mm	3.8 mm	5.4 mm	5.2 mm	0.5 mm	2.2 mm
2.4 mm	2.09 mm	1.97 mm	4.8 mm	4.6 mm	6.2 mm	6.0 mm	0.5 mm	2.2 mm
3.0 mm	2.65 mm	2.50 mm	5.6 mm	5.4 mm	7.0 mm	6.8 mm	1.0 mm	2.6 mm
5.7 mm	5.18 mm	4.95 mm	9.5 mm	9.3 mm	11.3 mm	11.1 mm	1.0 mm	3.7 mm

Table 2

Claron Part Number			Nominal Dimensions Ød           ØD         T Max.        O-Ring 1                          1                                        Section					Claron Part Number			Nominal Dimensions Ød           ØD         T Max.       O-Ring 1                          1                                        Section
BS 005 BS 006 BS 007 BS 008 BS 009 BS 010 BS 011 BS 012 BS 013 BS 014 BS 015 BS 016 BS 017 BS 018 BS 019 BS 020 BS 021 BS 022 BS 023 BS 024		0.109 0.125 0.156 0.187 0.219 0.250 0.312 0.375 0.437 0.500 0.562 0.625 0.687 0.750 0.812 0.875 0.937 1.000 1.062 1.125		0.234 0.250 0.281 0.312 0.344 0.375 0.437 0.500 0.562 0.625 0.687 0.750 0.812 0.875 0.937 1.000 1.062 1.125 1.187 1.250		BS 113 BS 114 BS 115 BS 116 BS 117 BS 118 BS 119 BS 120 BS 121 BS 122 BS 123 BS 124 BS 125 BS 126 BS 127 BS 128 BS 129 BS 130 BS 131 BS 132				0.562 0.625 0.687 0.750 0.812 0.875 0.937 1.000 1.062 1.125 1.187 1.250 1.312 1.375 1.437 1.500 1.562 1.625 1.687 1.750		0.750 0.812 0.875 0.937 1.000 1.062 1.125 1.187 1.250 1.312 1.375 1.437 1.500 1.562 1.625 1.687 1.750 1.812 1.875 1.937
BS 025 BS 026 BS 027 BS 028 BS 029 BS 030 BS 031 BS 032 BS 033 BS 034 BS 035 BS 036 BS 037 BS 038 BS 039 BS 040 BS 041 BS 042 BS 043 BS 044 BS 045 BS 046 BS 047 BS 048 BS 049 BS 050 BS 108 BS 109 BS 110 BS 111 BS 112		1.187 1.250 1.312 1.375 1.500 1.625 1.750 1.875 2.000 2.125 2.250 2.375 2.500 2.625 2.750 2.875 3.000 3.250 3.500 3.750 4.000 4.250 4.500 4.750 5.000 5.250 0.250 0.312 0.375 0.437 0.500		1.312 1.375 1.437 1.500 1.625 1.750 1.875 2.000 2.125 2.250 2.375 2.500 2.625 2.750 2.875 3.000 3.125 3.375 3.625 3.875 4.125 4.375 4.625 4.875 5.125 5.375 0.437 0.500 0.562 0.625 0.687	0.058         0.070 0.058         0.103				BS 133 BS 134 BS 135 BS 136 BS 137 BS 138 BS 139 BS 140 BS 141 BS 142 BS 143 BS 144 BS 145 BS 146 BS 147 BS 148 BS 149 BS 150 BS 151 BS 152 BS 153 BS 154 BS 155 BS 156 BS 157 BS 158 BS 159 BS 160 BS 161 BS 162	1.812 1.875 1.937 2.000 2.062 2.125 2.187 2.250 2.312 2.375 2.437 2.500 2.562 2.625 2.687 2.750 2.812 2.875 3.000 3.250 3.500 3.750 4.000 4.250 4.500 4.750 5.000 5.250 5.500 5.750		2.000 2.062 2.125 2.187 2.250 2.312 2.375 2.437 2.500 2.562 2.625 2.687 2.750 2.812 2.875 2.937 3.000 3.062 3.187 3.437 3.687 3.937 4.187 4.437 4.687 4.937 5.187 5.437 5.687 5.937	0.058         0.103

BS 206		0,500	0,750			BS 256	5,750	6,000
BS 207		0,562	0,812			BS 257	5,875	6,125
BS 208		0,625	0,875			BS 258	6,000	6,250
BS 209		0,687	0,937			BS 259	6,250	6,500
BS 210		0,750	1,000			BS 260	6,500	6,750
BS 211		0,812	1,062			BS 261	6,750	7,000
BS 212		0,875	1,125			BS 262	7,000	7,250
BS 213		0,937	1,187			BS 263	7,250	7,500
BS 214		1,000	1,250			BS 264	7,500	7,750
BS 215		1,062	1,312			BS 265	7,750	8,000
BS 216		1,125	1,375			BS 266	8,000	8,250
BS 217		1,187	1,437			BS 267	8,250	8,500
BS 218		1,250	1,500			BS 268	8,500	8,750
BS 219		1,312	1,562			BS 269	8,750	9,000
BS 220		1,375	1,625			BS 270	9,000	9,250
								0.058         0.139
BS 221		1,437	1,687			BS 271	9,250	9,500
BS 222		1,500	1,750			BS 272	9,500	9,750
BS 223		1,625	1,875			BS 273	9,750	10,000
BS 224		1,750	2,000			BS 274	10,000	10,250
BS 225		1,875	2,125			BS 275	10,500	10,750
BS 226		2,000	2,250			BS 276	11,000	11,250
BS 227		2,125	2,375			BS 277	11,500	11,750
BS 228		2,250	2,500			BS 278	12,000	12,250
BS 229		2,375	2,625	0,058	0,139	BS 279	13,000	13,250
BS 230		2,500	2,750			BS 280	14,000	14,250
BS 231		2,625	2,875			BS 281	15,000	15,250
BS 232		2,750	3,000			BS 282	16,000	16,250
BS 233		2,875	3,125			BS 283	17,000	17,250
BS 234		3,000	3,250			BS 284	18,000	18,250
BS 235		3,125	3,375
BS 236		3,250	3,500			BS 314	0,750	1,125
BS 237		3,375	3,625			BS 315	0,812	1,187
BS 238		3,500	3,750			BS 316	0,875	1,250
BS 239		3,625	3,875			BS 317	0,937	1,312
BS 240		3,750	4,000			BS 318	1,000	1,375
BS 241		3,875	4,125			BS 319	1,062	1,437
BS 242		4,000	4,250			BS 320	1,125	1,500
BS 243		4,125	4,375			BS 321	1,187	1,562
BS 244		4,250	4,500			BS 322	1,250	1,625
BS 245		4,375	4,625			BS 323	1,312	1,687
BS 246		4,500	4,750			BS 324	1,375	1,750
BS 247		4,625	4,875			BS 325	1,500	1,875
BS 248		4,750	5,000			BS 326	1,625	2.000        0.072         0.210
BS 249		4,875	5,125			BS 327	1,750	2,125
BS 250		5,000	5,250			BS 328	1,875	2,250
BS 251		5,125	5,375			BS 329	2,000	2,375
BS 252		5,250	5,500			BS 330	2,125	2,500
BS 253		5,375	5,625			BS 331	2,250	2,625
BS 254		5,500	5,750			BS 332	2,375	2,750
BS 255		5,625	5,875			BS 333	2,500	2,875
						BS 334	2,625	3,000
						BS 335	2,750	3,125
						BS 336	2,875	3,250

BS 337		3,000		3,375
BS 338		3,125		3,500
BS 339		3,250		3,625
BS 340		3,375		3,750
BS 341		3,500		3,875
BS 342		3,625		4,000
BS 343		3,750		4,125
BS 344		3,875		4,250
BS 345		4,000		4,375
BS 346		4,125		4,500
BS 347		4,250		4,625
BS 348		4,375		4,750
BS 349		4,500		4,875
BS 350		4,625		5,000
BS 351		4,750		5,125
BS 352		4,875		5,250
BS 353		5,000		5,375
BS 354		5,125		5,500
BS 355		5,250		5,625
BS 356		5,375		5,750
BS 357		5,500		5,875
BS 358		5,625		6,000
BS 359		5,750		6,125
BS 360		5,875		6,250
BS 361		6,000		6,375
BS 362		6,250		6,625
BS 363		6,500		6,875
BS 364		6,750		7,125
BS 365		7,000		7,375
BS 366		7,250		7,625
BS 367		7,500		7,875
BS 368		7,750		8,125
BS 369		8,000		8,375
BS 370		8,250		8,625
BS 371		8,500		8,875
BS 372		8,750		9,125
BS 373		9,000		9,375
BS 374		9,250		9,625
BS 375		9,500		9,875
BS 376		9,750		10,125
BS 377		10,000		10,375
BS 378		10,500		10,875
BS 379		11,000		11,375
BS 380		11,500		11,875
BS 381		12,000		12,375
BS 382		13,000		13,375
BS 383		14,000		14,375
BS 384		15,000		15,375
BS 385		16,000		16,375
BS 386		17,000		17,375
BS 387		18,000		18,375
BS 388		19,000		19,375
BS 389		20,000		20,375
BS 390		21,000		21,375
BS 391		22,000		22,375
BS 392		23,000		23,375
BS 393		24,000		24,375
BS 394		25,000		25,375
BS 395		26,000		26,375
issue 1 – 20/10/98
BS 425						4,500	5,000
BS 426						4,625	5,125
BS 427						4,750	5,250
BS 428						4,875	5,375
BS 429						5,000	5,500
BS 430						5,125	5,625
BS 431						5,250	5,750
BS 432						5,375	5,875
BS 433						5,500	6,000
BS 434						5,625	6,125
BS 435						5,750	6,250
BS 436						5,875	6,375
BS 437						6,000	6,500
BS 438						6,250	6,750
BS 439						6,500	7,000
BS 440						6,750	7,250
BS 441						7,000	7,500
BS 442						7,250	7,750
BS 443						7,500	8,000
BS 444						7,750	8,250
BS 445						8,000	8,500
BS 445A						8,250	8,750
BS 446						8,500	9,000
BS 446A						8,750	9,250
BS 447						9,000	9,500
BS 447A						9,250	9,750
.210                       BS 448                9.500      10.000      0.104         0.275
BS 448A						9,750	10,250
BS 449						10,000	10,500
BS 449A						10,250	10,750
BS 450						10,500	11,000
BS 450A						10,750	11,250
BS 451						11,000	11,500
BS 451A						11,250	11,750
BS 452						11,500	12,000
BS 452A						11,750	12,250
BS 453						12,000	12,500
BS 454						12,500	13,000
BS 455						13,000	13,500
BS 456						13,500	14,000
BS 457						14,000	14,500
BS 458						14,500	15,000
BS 459						15,000	15,500
BS 460						15,500	16,000
BS 461						16,000	16,500
BS 462						16,500	17,000
BS 463						17,000	17,500
BS 464						17,500	18,000
BS 465						18,000	18,500
BS 466						18,500	19,000
BS 467						19,000	19,500
BS 468						19,500	20,000
BS 469						20,000	20,500
BS 470						21,000	21,500
BS 471						22,000	22,500
BS 472						23,000	23,500
BS 473						24,000	24,500
BS 474						25,000	25,500
BS 475						26,000	26,500
0.072         0

BS  0031-16		3,5	6,0				BS  0195-30	20	25
BS  0041-16 BS  0051-16		4.5 5.5	7,0				BS  0215-30	22	27
BS  0061-16 BS  0071-16		6.5 7.5	9,0				BS 0225-30 BS 0245-30	23 25	28 30
BS 0081-16		8,5	11,0				BS 0255-30	26	31
BS 0091-16 BS 0101-16 BS 0111-16		9.5 10.5 11.5	12.0 13.0				BS 0265-30 BS 0275-30	27 28	32
BS 0121-16		12,5	15,0				BS 0295-30	30	35
BS 0131-16		13,5	16,0				BS 0315-30	32	37
BS 0141-16		14,5	17,0	1,4		1,6	BS 0325-30	33	38
BS 0151-16 BS 0161-16 BS 0171-16		15.5 16.5 17.5	18.0 19.0				BS 0345-30 BS 0355-30	35 36	40
BS 0181-16		18,5	21,0				BS 0365-30	37	42
BS 0191-16		19,5	22,0				BS 0375-30	38	43
BS 0221-16 BS 0251-16 BS 0271-16		22.5 25.5 27.5	25.0 28.0 30.0				BS 0395-30 BS 0415-30 BS 0425-30	40 42 43	45 48
BS 0291-16		29,5	32,0
BS 0321-16		32,5	35,0				BS 0445-30	45	50
BS 0351-16 BS 0371-16		35.5 37.5	38.0 40.0				BS 0495-30 BS 0545-30	50 55	55
BS 0036-24 BS 0046-24		4 5	8 9				BS 0555-30 BS 0575-30	56 58	61 63
BS 0056-24		6	10
BS 0066-24		7	11				BS 0595-30	60	65
BS 0076-24		8	12				BS 0635-30	64	69
BS 0086-24 BS 0096-24 BS 0106-24		9 10 11	13 14 15				BS 0645-30 BS 0695-30 BS 0745-30	65 70 75	70 75 80
BS 0116-24		12	16
BS 0126-24		13	17				BS 0795-30	80	85
BS 0136-24 BS 0146-24		14 15	18 19				BS 0845-30 BS 0895-30	85 90	90 95	1,4	3,0
BS 0156-24		16	20				BS 0945-30	95	100
BS 0166-24		17	21				BS 0995-30	100	105
BS 0176-24		18	22
BS 0186-24 BS 0196-24 BS 0206-24		19 20 21	23 24 25				BS 1045-30 BS 1095-30 BS 1145-30	105 110 115	110 115 120
BS 0216-24		22	26				BS 1195-30	120	125
BS 0246-24		25	29				BS 1245-30	125	130
BS 0276-24 BS 0296-24 BS 0316-24		28 30 32	32 34	1,4		2,4	BS 1295-30 BS 1345-30	130 135	135
BS 0346-24		35	39				BS 1395-30	140	145
BS 0356-24		36	40				BS 1445-30	145	150
BS 0376-24		38	42				BS 1495-30	150	155
BS 0396-24 BS 0416-24		40 42	44				BS 1545-30	155	160
BS 0446-24		45	49				BS 1595-30	160	165
BS 0456-24		46	50				BS 1645-30	165	170
BS 0476-24 BS 0496-24		48 50	52 54				BS 1695-30 BS 1745-30	170 175	175 180
BS 0516-24 BS 0536-24		52 54	56				BS  1795-30	180	185
BS 0546-24		55	59				BS  1845-30	185	190
BS 0576-24 BS 0586-24 BS 0596-24		58 59 60	62 63 64				BS  1895-30 BS  1945-30 BS  1995-30	190 195 200	195 200 205
BS 0616-24		62	66
BS  0626-24		63	67				BS  2045-30	205	210
BS  0646-24 BS  0676-24 BS  0696-24		65 68 70	69 72 74				BS  2095-30 BS  2195-30 BS  2295-30 BS  2395-30	210 220 230 240	215 235
BS  2495-30

BS  0443-57 BS  0453-57 BS 0493-57 BS 0523-57 BS 0543-57 BS 0553-57 BS 0593-57 BS 0623-57 BS 0643-57 BS 0693-57 BS 0743-57 BS 0793-57 BS 0843-57 BS 0893-57 BS 0943-57 BS 0993-57 BS 1043-57 BS 1093-57 BS 1143-57 BS 1193-57 BS 1243-57 BS 1293-57 BS 1343-57 BS 1393-57 BS 1443-57 BS 1493-57 BS 1543-57 BS 1593-57 BS 1643-57 BS 1693-57

45 46 50 53 55 56 60 63 65 70 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170

55 56 60 63 65 66 70 73 75 80 85 90 95 100 105 110 115 120 125 130 135 140 145 150 155 160 165 170 175 180

1.8            5.7

BS  1743-57 BS  1793-57 BS  1843-57 BS  1893-57 BS  1943-57 BS  1993-57 BS  2043-57 BS  2093-57 BS  2143-57 BS  2193-57 BS  2293-57 BS  2393-57 BS  2493-57 BS  2593-57 BS  2693-57 BS  2793-57 BS  2893-57 BS  2993-57 BS  3193-57 BS  3393-57 BS  3593-57 BS  3793-57 BS  3993-57 BS  4193-57 BS  4393-57 BS  4593-57 BS  4793-57 BS  4893-57 BS  4993-57

175 180 185 190 195 200 205 210 215 220 230 240 250 260 270 280 290 300 320 340 360 380 400 420 440 460 480 490 500

185 190 195 200 205 210 215 220 225 230 240 250 260 270 280 290 300 310 330 350 370 390 410 430 450 470 490 500 510

1,8

5,7