Product introduction

Multi-Purpose Gland Packing for
Chemical Applications
1. Introduction
To date, various types of carbon-fiber products, whichhave heat and chemical resistance, have been used as
gland packings for chemical applications. However, for aparticular product, different types of packing should beused depending on how the product is used. When
PTFE dispersion, graphite
particulate, lubricating oil

several types of packing are taken from stock and used,
there is a risk that the wrong type of packing might beincurring safety risks.

Figure1

Winter 2018

Carbon fiber

used, possibly causing damage to plant operation andOutline illustration of No. 6137 series

We have developed a new product based on carbon
fiber like the conventional product, but when used in asingle product, different types of packing are notrequired depending on how the single product is used.
The new product can also be used under diverse

No.34

conditions in a single product, and offers the same heat,pressure and chemical resistance. Therefore, the new
packing improves the stability and safety of operation,and helps reduce inventory.

2. Composition
No. 6137 series is based on gland packing manufactured
as follows:（1）Carbon fiber is treated with PTFE

Figure2External view of No. 6137 series

3. Characteristics

dispersion.（2）The cross section of the treated carbon① No. 6137 series is suitable for a wide range offiber is braided into a square shape.（3）The shaped

applications, including valves, pumps, equipment,carbon fiber is finished with PTFE dispersion andand others.

graphite particulate. Both oil-containing and oil-free② The main materials of No. 6137 series are carbon

types are available. The three types, No. 6137, No. 6137-

fiber and PTFE dispersion, which have excellent

O, No. 6137-SO, can be selected depending on thechemical resistance. Therefore, No. 6137 series canapplication.

be used for most fluids except strongly oxidizing
fluids.
③ No. 6137 series is suitable for a wide range of38

Multi-Purpose Gland Packing for Chemical Applications

applications, resulting in excellent cost performance（inventory reduction）.

6. Specifications
Nominal dimension: □ 3.0–25.0 mm
Packing unit: 3 m（Ring-shape molding is also available.）

4. Applications
・Common applications of No. 6137 series
N o. 6137 series can be used for valves, pumps,

7. Results of functional tests

packings of seal devices, etc., all of which handle

7-1）Evaluation of basic characteristics

chemical fluids（except for oxidizing acids andBasic-characteristics tests are conducted to evaluateoxidizing agents including concentrated sulfuric acidcompressive-strain characteristics, sliding characteristics,

and concentrated nitric acid）.

sealing characteristics in valves, and use as glandpacking.

・‌No. 6137 can be used in valves and devices forapplications designated as oil-free processing, requiring

Test conditions:
Table2no contamination by lubricating-oil, and for prevent
softening and loosening of the packing due tolubricating-oil reduction.
・‌No. 6137-O can be used for valves and devices as well

Winter 2018as high-speed pumps including turbo pumps, all of

No.6137-O，No.6232（1）Refer to“Figure 3. Outline illustration ofTest equipment
basic-characteristics test equipment.”
Evaluation of basic characteristics
Packing dimension φ20×φ33×6.5H

It can also be used as a substitute for No. 6232 and No.

Packing qty
Stem radialclearance
Packing stress6262（thus reducing inventory through part-number

Fluid

Nitrogen gas

Fluid pressure

1.0 ～ 9.8 MPa

which require low torque and gas-sealing performance.

integration）.
・‌No. 6137-SO can be used for high-speed pumps such as

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Gland packing

Test conditions

turbo pumps, which need greater heat resistance than

6 rings
0.5mm
4.9 ～ 58.8 MPa

Note（1）: No. 6232 is used for valves and reciprocating equipment.

Outline of the test method:

No. 6137-O in devices which require low torque and①

Mount the gland packing in a test jig.

gas-sealing performance.

②

F asten the packing under a given contactpressure using a compression tester.

③ Measure the height and stem torque of the packing.

5. Usable range
Table1
Application
Maximum service
temperature
Maximum
service pressure
ANSI rating
Maximum
service speed
PV tolerance
pH range④Product specifications

Valve

Pump

the leak rate.
Device260 ℃
15.5 MPa

1.6MPa⑤

I ncrease the packing

stress in a stepwise

fashion, and repeat steps ② to ④ .
9.8MPaClass 900―――

20m/s（1）5m/s（1）―

14.7MPa･m/s（1）―0 〜 14Note（1）: ‌Maximum service speed and PV tolerance are applicable toNo. 6137-O and No. 6137-SO.

39Load fluid pressure on the packing and measure

At start
During sliding
At start
During sliding

Simplified μK value

Compression tester

Stem

GlandFluid pressure（MPa）

Product introduction

Packing stress（MPa）

Packing stress（MPa）

Figure6 Sliding characteristics（μk value） Figure7

Sealing properties

7-2）Reciprocation-tolerance test
Gland packing

Reciprocation-tolerance tests are conducted toevaluate the sliding-resistance characteristics andsealing characteristics against reciprocating motions ofthe gland packing for valves.
Table3Pressure port

Test conditions

Gland packing No.6137-O，No.6232（１）Refer to“Figure 9. Outline illustration of a
Test equipment
reciprocation-tolerance tester.”
Packing dimension φ20×φ33×6.5H
Packing qty

Figure3 Outline illustration of basic-characteristics test equipment

The results of the basic-characteristics evaluation are
shown in Figures 4 to 7.
No. 6137-O had a slightly lower compression ratio,
weaker stem resistance, which is a sliding characteristic,
and improved performance than the conventional
product No. 6232. Regarding sealing properties, bothFigure4 Compression characteristics

Stem resistance per unit contact-surface area（N/mm2 ）Compression ratio（％）

specimens showed equivalent results.

Packing stress（MPa）

Packingarrangement
Fluid

Test results:

8 rings（2 rings + lantern ring + 6 rings）
×2

Water and heated water

Test temperature 260℃
Stem radial
0.7 mm（inner diameter = φ21.4）
clearance
Sliding number 1000 reciprocations × 3 cycles（3000 reciprocations）
Initial packing stress: 39.2 MPa
Additional packing stress: 39.2 MPa
Stem stroke: 50 mm
Stem operating
Stem speed: 25 mm/sec
conditions
Stem stop: 1 sec
On heating: 10.2 MPa
Fluid pressure When withstanding pressure at room temperature:
11.0 MPa
Packing stress

Note（1）: No. 6232 is used for valves and reciprocating equipment.
At start
During sliding
At start
During sliding

Test results:
Figure 10 shows the results of the reciprocationtolerance tests.
No. 6137-O had a weaker stem resistance, which is a

Packing stress（MPa）

Figure5 Sliding characteristics

sliding characteristic, and improved performance thanthe conventional product No. 6232. Regarding sealing
properties, both specimens showed equivalent results.

40

Winter 2018

Compression（loading packing stress）

No.34

Multi-Purpose Gland Packing for Chemical Applications

At 260ºC at the time ofpartial heating
When withstanding pressure
at room temperature

Pressure

Staffing box on thefollowing side
Load cell（measuringcontact pressure ofpacking）

Staffing box on thedriving side

Band heater

Pressure port
Gland
Leak-off

Load cell（measuringstem resistance）

Stem1000
reciprocations

Fluid temperature（℃）

Figure81000
reciprocations

1000
reciprocations

Figure9 Outline illustration of a reciprocation-tolerance tester

Outline of test cycles1000 reciprocations

1000 reciprocations

1000 reciprocations

At start
During sliding
At start
During sliding

Leak rate（cc/h）

following side
driving side
following side7-3）Large-bore pressure test

At coolingAt the time of temperature rise

At cooling

Results of reciprocation-tolerance tests

At room temperature

At the time of temperature rise

Figure10

At room temperature

At the time of temperature rise

Tightening

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At cooling
Tightening

driving sideAt room temperature

Winter 2018

Stem resistance（kN）

Hydraulic cylinder
Lantern ringfor driving
Gland packing
Gland packing（below lantern）（above lantern）

Outline of the test method:

Large-bore pressure tests are conducted to evaluate①

Mount the gland packing in a test jig.

the pressure tightness of a gland packing.

②‌Use a torque wrench to tighten the gland packing
to a given packing stress.

Table4

Test conditions

No.6137-O
Refer to“Figure 11. Outline illustration ofTest equipment
large-bore pressure tester.”
Packing dimension φ80×φ112×16.0H③

Gland packing

Packing qty

using a water-pressure booster.
④

packing or leaks.

Stem radial clearance 1.2 mm（inner diameter = φ82.3）
39.2 MPa

Temperature

Room temperature

FluidFluid pressure

41Water
15.5 MPa, 19.4 MPa, 23.3 MPa（Maximum, ANSI Class 900 × 1.5）

‌After keeping the pressure for 30 minutes,
check whether the fluid penetrates through the6 rings

Packing stress‌Apply a given fluid pressure to the sample⑤‌ncrease the fluid pressure in a stepwise fashion,
and repeat the check of step ④ .

Product introduction

equipment. Through the alternate switching, theperipheral speed and discharge pressure are varied,

StemPacking presser
Gland packing

creating much more severe conditions than underregular operation. Under such conditions, the leak rateand stem-torque characteristics were evaluated.

Stop
Pressure port

Figure11

Outline illustration of a large-bore pressure tester

Test results:
Table 5 shows the results of the large-bore pressure

Figure12

Inverter activation cycle

Test pump : General-purpose, single-suction centrifugal pump
Motor: 4-phase, 200 V（60 Hz）, 4 poles, 5.5 kW
Pump bore : 65 × 50
① : Test pump
② : Pump for pressing pressure

test.
Pressure tightness was improved from the diameter

Thermometer

6232; No. 6137-O can be used at the diameter of up toValve for discharge-pressureadjustment

ANSI Class 900.
Table5Results of large-bore pressure tests

Fluid pressure（MPa）

19.4

23.3

ANSI rating

Class 900 × 1.25

Class 900 × 1.5

Penetrating

None

None

Leakage

None

None

Figure13 Outline illustration of a long-term inverter-tolerance tester

Test results:
Tables 7 and Figure 14 show the results of theinverter-tolerance tests.

7-4）‌Test to evaluate long-term durability

In the tests, varying pressures and peripheral speeds

against inverter using an actual

were applied to the samples through inverter

equipment pump

operation of a rotary pump of actual equipment.

In inverter-tolerance tests, the rotation of a rotary

Under varying pressures and peripheral speeds, No.

pump’s motor is switched alternatingly between 60

6137-O showed stable tolerance and had equivalent

Hz and 30 Hz using an inverter in the pump of actual

leak rate and sliding resistance to the conventional

Table6

product No. 6262.

Test conditions

Test equipment

Refer to“Figure 13. Outline illustration of along-term inverter-tolerance tester.”Gland packing

No.6137-O，No.6262（１）Packing dimensionＨ
φ35×φ51×8（4rings）

FluidWaterTemperature

Course of events

Pushing pressure

0.5MPaTest frequency

60Hz30Hz

Rotation

1800rpm

900rpmPeripheral speed

3.30m ／ s

1.65m ／ s

Discharge pressure

0.8MPa0.6MPaPV value

2.64MPa・m ／ s

0.99 MPa・m ／ s

Winter 2018of ANSI Class 600 for the conventional product No.

Pressure 1：Pressing pressuregauge
2：Discharge pressure

Water tank

Table7

Results of inverter tests

Operation time
Fluid temperature（1）Gland packing
Frequency
Minimum value
Leak rate（２）Maximum value（cc/min）
Average

Approximately 1000 hours
Course of events
No.6137-O
No.6262（３）60Hz30Hz
60Hz30Hz
66991815909014132626

Note（1）: ‌Fluid temperature fluctuates depending on packing’s
frictional heat and piping resistance.
（2）: ‌Leak rate just after inverter activation（3）: ‌Test results do not include time for running-in and initialadjustment.

Note（1）: No. 6262 is used for rotary pumps and rotary devices.

42No.34

Leak rate

Multi-Purpose Gland Packing for Chemical Applications

Temperature（℃）

Operation time（h）

Winter 2018

Sliding torque（N・m）

Operation time（h）

Operation time（h）

Figure14 Results of inverter tests

8. Conclusion
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inventory management and reducing the risk
associated with product mis-selection.

With the products described here, different types ofWe will continue to develop new products to satisfy

products do not need to be selected depending on thethe varying needs of individual users.

application, thus improving the efficiency of the43

Syuuzi Sugawa

Masato Hamade

Corporate Research andDevelopment Group
Product Development DivisionⅠ

Corporate Research andDevelopment Group
Product Development DivisionⅠ