Page 386 - ParkerBrassCatalog2010

Parker Hannifn Corporation

Parker Brass Products Division

Otsego, Michigan

Catalog 3501E

General Technical

N6

N

Peripheral sealing of

parallel threads

Pressure-tight joints of screwed

connections with parallel threads

are achieved by placing a seal

between the two machined faces

Flat seals

Washers and rings are

manufactured in many different

materials including copper,

aluminium, fber, plastics, etc.

The tightening torque at assembly

must be carefully selected so as

to avoid compressing the seal to

the point of extrusion. As a general

rule, the ftting should be tightened

with an additional 1/4 wrench turn

from the fngertight position.

O-rings

Depending upon the confguration

of the female port or male thread,

O-Ring seals are ftted with or

without back-up washers, and can

be fully retained in a captive seal.

Pipe Thread Assembly

The two British Standard pipe thread forms used for Parker’s standard

product are manufactured in a tighter tolerance range than required by

the standards in order to facilitate the assembly and mating of fttings

produced by the two different standards. In general, BS21 threads

do not necessarily mate with BS2779 threads at tolerance overlap

conditions, but fttings located within this catalog can be assembled as

follows:

External Thread

Mating Internal Thread

G-BS2779 (parallel)

Rp-BS21* (parallel)

Rs-BS21 (parallel)

Rp-BS21 (parallel)

G-BS2779 (parallel)

R-BS21 (taper)

Rp-BS21 (parallel)

Rc-BS21 (taper)

G-BS2779 (parallel)

*This thread must be manufactured within a

reduced tolerance range to always assemble with

the G series external thread.

British Standard ISO Metric Screw Threads

They are commonly used in miniature pneumatic applications

because of the availability of small thread diameters and are also used

extensively in the automotive industry. There are two forms of sealing

on metric screw threads.

• O-ring sealing into a profled port in accordance with ISO 6149.

• Peripheral sealing with a copper or bonded washer in accordance

with ISO 261 and 262.

Flaring Instructions

In order to properly fare copping tubing for use with Parker 45° Flared

Fittings and Inverted Flared Fittings, the following procedures and

specifcations should be met in preparation and make-up of fares.

1) CUTTUBEWITHTUBE CUTTER:

To minimize the burr and workhardening, use a light feed on the

cutting wheel and make several revolutions.

2) REAMTHETUBING:

Cutting with a tube cutter will always create a burr. The burr must be

removed to obtain maximum sealing surface. Remove only the burr,

do not remove material from the original wall thickness. Also clean

the tube end thoroughly to remove burrs.

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ebuT

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retemaiD

elgniSB

suidaReralF

elgniSD

llaWeralF

ssenkcihT

ni

.xaM

.niM

?

10.0

.xaM

8/1

61/3

4/1

61/5

181.0

942.0

523.0

404.0

171.0

932.0

513.0

883.0

20.0

530.0

940.0

8/3

61/7

2/1

61/9

784.0

165.0

326.0

676.0

174.0

545.0

706.0

066.0

20.0

560.0

380.0

8/5

4/3

8/7

1

847.0

619.0

140.1

751.1

237.0

009.0

520.1

141.1

20.0

590.0

901.0

021.0

TUBE

OD

A

SLIGHT FLAT PERMISSIBLE

D

B

91

°

89

°

FLARE

SEAT

47

°

43

°

3) FLARETUBING:

Flare with a compression or generating type faring tool. Follow tool

manufacturer’s instructions for: (A) positioning the tube in tool and

(B) for the correct number of turns on the feed handle.

4) INSPECTTUBING:

The fare cone should be checked for a smooth surface on the I.D. of

the cone and measure with micrometer over largest O.D. for proper

size. (See dimensions below for fare size for each tubing size.)