New technology in hose reinforcing machines.

Our records and information indicate that braiding as reinforcement in hose manufacturing was introduced at the turn of the last century. At first, reinforcing was in the form of yarn braiding using vertical-type braiders. Wire reinforcing was introduced to the hose industry in the mid-1920s, and by 1929 horizontal-type machinery was being produced to manufacture wire hose on steel mandrels 15 to 18 meters in length. These early braiding machines were slow, employed the maypole principle and had carrier designs as used in the textile fields that produced such items as lace, corset cord, etc. The advent of automotive hydraulic brakes in the mid-1930s and more widespread use of hydraulics on machine tools, construction, mining and drilling equipment during the 1940s and 1950s rapidly expanded the hose market. Consequently, new and established hose manufacturers began demanding machinery that would be faster, more reliable and more economical to operate. Many hose braiding manufacturers, such as Magnatech International (formerly Rockwell Inter.Graphic & Systems Division), Mayer Industries, Wardwell, Spirka, Cartar and Panjin Rubber & Plastic Machinery Works have made many braiding machines and winding machines for rubber hose manufacturers. This article mainly introduces their current situation, development, applications in the rubber hose industry, as well as related components, as a reference for choosing suitable equipment for hose manufacturers.

Magnatech 225-II high speed braider

During the mid-1960s, design efforts were started on the first high-speed, large supply package hose reinforcing braider. The first efforts in improving hose reinforcing braiders came in the form of carrier design changes. The means for strand tensioning were improved, and braid strand supply package sizes were increased. The increase in package size, especially in the case of wire, approached the limitations of the conventional horn gear type maypole braider. The cast iron carrier feet, subjected to constantly changing angular acceleration force, were further plagued by 300 to 400 pounds (1,335 to 1,780 Newtons) of force exerted by the cantilevered supply packages. Carrier feet, deck plates and horn gears were being strained to their maximum limits. In order to meet the requirements of rubber hose manufacturers, Rockwell developed and produced the 225-II shuttle-type maypole braider (maypole working principle) with a braiding speed of 225 rpm. That means: 45 carrier rpm for the 20-carrier module, 37.5 carrier rpm for the 24-carrier module and 25 carrier rpm for the 36-carrier module. The wire capacity for every bobbin is 8.15 kg and the yarn package is 2,376 cu. cm. (145 cu. in.). Moving of the carrier core is controlled by a positive shuttle system. This module can be utilized to make a completed system for producing high pressure rubber hoses when combined with other modules such as RB-2 Braider, WSW-III precision wire spiral winder, haul off, spiral tape winder, wire helix server, let-offs and take-ups.

RB-2 rotary braider

During the 1970s, the engineers designing braiding machines began to develop other new braiding machines. The development of a unique modified four-bar linkage for guiding the outer-carrier braid strands over and under large inner carrier supply packages was the breakthrough that insured that their goal was achievable. The only forces this linkage had to withstand were braid strand tensions of 30 pounds (133.5 Newtons) and dynamic forces in the order of 150 pounds (668 Newtons). Five years of design, extensive laboratory development and field-testing resulted in the 1980 introduction of the Rockwell RB-2 rotary braider. This braider is one of the key rubber hose reinforcing braiders that emerged as carrier design changed, the means for strand tensioning was improved and braid strand supply package sizes were increased. The increase in package size (especially in the case of wire) approached the limitations of the conventional horn gear type maypole braider. This eliminated the speed limitations due to the dynamic reversal forces, the unbalancing with loads and the high cantilever forces that are associated with maypole up to 8.17 kg/bobbin. The machinery data of a Standard RB-2 rotary braider is as shown in table 1.

According to the data in table 1, the RB-2 can be installed with 16 carriers, 20 carriers, 24 carriers or 36 carriers, decreasing change time of carriers. For example, a 24 carrier RB2 rotary braider using yarn in the carriers has a turn speed of 75 rpm. When we use this braider to produce 12.7 mm (0.5 inch) diameter yarn-reinforced hoses, the annual output of this hose will be 880,000 meters. If we use a 36 carrier braider to produce yarn reinforced hose, for example, the turn speed will be 50 rpm, the inner diameter of hose is 25.4 mm and the annual output would be 1,460,000 meters. If producing wire-reinforced rubber hoses, when its turn speed is 40 rpm, the annual output would be 1,160,000 meters. Whether 24 carrier or 36 carrier braider, the bobbin capacity for wire is still 11.3 kg (25 pounds) and the bobbin capacity for yarn is 3,606 cm (220 inches). The RB-2 braider is divided into two upper parts and two lower parts in the construction with advanced design. It has excellent machinery properties, such as fast braiding speed, large bobbin capacity and easy operating for operators, etc. Compared to a traditional braider, the RB-2 braider's productivity is increased up to 200%, the bobbin changing time is decreased up to 35% and it simplifies the process of threading yarn or wire. Also, the bobbin size for yarn is the same as the bobbin size for wire. The operators can operate this braider easily because of the following features:

* The power former can produce a uniform locked in braid;

* an automatic track oil system for the inner carriers;

* the exhausted (empty) bobbin has photoelectric stop motion;

* the deck speed is precisely controlled by change gears:

* patented motion provides positive control and a defined path for outer strands; and

* an on-demand let off and a simple path for strand tension reliability.

Very important is the MICS electronic control system installed in the RB-2 wire-yarn rotary braider, so the braider has excellent reliability and adaptability. The RB-2 yarn-wire rotary braider is made with standard components and design. According to the demands of rubber hose production, it can be combined with winding machines such as a WSW-III precision wire spiral winder, tape winder and haul off to manufacture high pressure rubber hoses with high quality. Thus, people have paid more attention to this braider, and many hose manufacturers continue to use this kind of braider to this day.

MR-11S braider

Mayer Industries introduced the MR-11S, a patented braiding system, in the 1970s in order to meet the requirements of rubber hose manufacturers. The MR-11S system is a maypole braider that produces a two-over, two-under braid pattern. It has been proven over the years for its high productivity, low maintenance and versatility in hose size and design. The shuttle and carrier of the MR-11S system accepts a variety of bobbins and bobbin configurations, including: single let-off wire (9 Kg/20 lbs.), single let-off yarn (4,097.5 cm./250 in.), super large yarn package (5,162.8 cm./315 in.) and double let-off wire (6.3 kg/36 lbs.). Because of its unique design, the MR-11S system is the only braider that can produce wire-reinforced hoses ranging in size from 4 mm to larger than 38 mm on the same deck. And no other braider has a package size large enough to produce a yarn-reinforced hydraulic hose exceeding 3,000 meters (100,000 ft.) in length. This kind of braider has superior braiding technology for superior quality and performance.

It has a positively controlled shuttle transfer. Since the MR-11S has no deck plates, the open junctions of conventional braiders are eliminated. The shuttle smoothly transfers from one rotor to the next by a cam track system that reduces shuttle movement.

The MR-11S eliminates angular acceleration. At any position during the inner or outer cycle, the MR-11S takes the outer or inner braid point from the carrier with a minimum of interference. This is achieved by planetary gears that compensate for the angular acceleration and align the payoff roller to the braid point. This maintains a consistent tension pattern, resulting in better quality of both yarn and wire braiding.

The MR-11S has a minimum tension cycle. The slack between the outer and inner cycle is stored on the compensator plates, thus minimizing the tension variation to less than 20% during the braiding cycle. This is a value not achieved by any other braiding system.

Also, the machine uses ultrasonic sensors to maximize productivity. Exclusive on the MR-11S are ultrasonic sensors that constantly measure the diameter of the yarn/wire bobbins on the deck in order to maximize the speeds according to the bobbin weight. The MR-11S operates on the principle that as the bobbin weight decreases, the machine speeds up, thereby increasing productivity. Measuring the bobbin diameter and correlating the product on the MR-11S, the ultrasonic sensors calculate the proper rotor rpm for the largest rotor. The rpm is then adjusted and will be corrected accordingly on a continual basis throughout the production process. The MR-11S features a microprocessing system to assist in operating and monitoring the machine for the ultimate in cost saving efficiency and quality control. This system has additional capabilities such as:

* Providing data for statistical process control;

* automatically operating and monitoring its performance;

* recording production in meters or feet;

* indicating maintenance schedules;

* informing the operator of all operations/malfunctions at all times:

* recording machine stops and displaying the reason for the stop, such as broken braid, broken wire, low oil pressure, empty bobbin, bobbin change, etc.; and

* it can display the running efficiency of the machine.

For a complementary braiding system, add the MC-2 caterpillar haul off. Whether it is a wire or yarn braided product, there is less pressure with the MC-2 caterpillar haul off. It is the ideal solution for flexible, rigid and mandrel-less operations. Pressure on the hose is distributed better than on competitive systems because of the long track length, 812 mm (32 in.). The MC-2 also features front mounting pads, available in a variety of materials to match required specifications. These can be removed from the chain while still on the machine for easy maintenance. Other features include a hose guide at each end; a timing belt shell drive for quiet, long-life operation; change gears for easy speed settings (same gears as MR-11S); an optional P.I.V. drive: a tension scale allowing repeatable pressure setting; permanently lubricated sealed gear boxes, etc. (table 2).

WSW-III precision wire spiral winder

In order to meet the requirements for making high or super-high pressure hose, many hose manufacturers need a WSW wire spiral winder to meet requirements such as in SAE J517, for making four spiral wire, four spiral heavy wire hose (100R10) and six spiral heavy wire hoses (100R12). Rockwell designed and produced the WSW-III precision wire spiral winder early in the 1980s. Many hose manufacturers have paid more attention to this wire spiral winder because of its super properties, such as a very high productivity of its turntable up to 75 rpm, a wire carrying capacity of up to 1,400 lbs. per turntable, preforming of wire immediately prior to laying wire onto the hose tube and a choice of bobbin assemblies to suit the production demands.

The WSW-III offers new capabilities of wire reinforcing for broad ranges of hose constructions, such as making super pressure hose with diameters from 6 mm to 51 mm--90, 120, 150 or 180 ends per turntable.

Bobbins are mounted on needle bearings and equipped with a disc brake to prevent bobbin overrun. Only one external adjustment is necessary for all bobbins within a group (dividing 3 group, 4 group, 5 group or 6 group). Turntable speed is accomplished by utilizing only one change gear, enabling greater control of the helix angle. Self-centered preforming insures wire-to-wire uniformity in both tension and preform. It is possible to adopt a longitudinal or spiral interlayer stock method. A fully enclosed change gear precisely controls turntable speed (each turntable's spiral angle will be 54[degrees], 44' or other spiral angle, as shown in table 3).

Pneumatic braking of the turntable was adopted to prevent unwinding of spiral lays when the machine stopped. This winder can be utilized with a bobbin winder, such as the BW-6a-1. Constant bobbin speed is 1,000 rpm. The wire capacity for one bobbin can be used for a whole group of bobbin assemblies, because the pre-determined length (feet or meters), reset counter and totalizer, and wire breakage stop system are installed in this module. Thus, the wire length of every bobbin is correctly the same.

A precision wire spiral winder with excellent properties should wind high performance rubber hose to meet related standards or specifications, and should have high productivity (that means the winder should have large wire carrying capacity and shorter time of changing bobbin wire). This kind of winder has great advantages in these areas. The number of bobbins in a turntable depends on the hose size. More bobbins enable a greater hose size range, but the capacity of each is relatively small. So the engineers design four sets of bobbin groups, including: 3/group, 4/group. 5/group and 6/group. Adopting the 6/group allows 180 ends per turntable for producing rubber hoses that are from 6 to 51 mm diameter (table 4). Using table 4, if we adopt 4/group, the wire capacity is large (more than 6/group by about 50%) and productivity is higher (more than 70%).

Specifications for a WSW-III include: Size Of 2.180 mm x 1,632 mm, weight of 3,030 kg; haul off size of 2,121 mm x 1,156 mm and weight of 2,562 kg.

Karg rotary vertical braiding machine

Karg is another braiding machine manufacturing that designs and produces some rotary vertical braiding machines, such as Model 36-V and Model 24/24H. The machinery is the same in principle. The Model 36-V machine has a rotary braiding deck consisting of 36 carriers in a circular path: 18 rotate clockwise and 18 rotate counterclockwise. This braiding machine is designed to produce a two over two braiding pattern with suitable braiding materials. The minimum practical tension level for most types of yarn used on this machine in hose construction is 2.5 lbs (1.13 kg); while the carriers and braiding mechanism have been designed to operate from a tension level of 1.0 to 10 lbs. (0.45 to 4.5 kg). Through testing, we have found that 2.5 lbs. (1.13 kg) is the practical lower tension limit at 64 rpm. The minimum tension level for braiding at 64 rpm is dependent on several factors, such as the weight per unit length of yarn, the surface characteristics of the yarn and the uniformity of winding of multiple ends of yarn. The machine capacity for braided hose is 2" (50.8 mm) diameter maximum, as measured over the completed braid. The braid pitch is adjustable, via change gears, from 0.86" (21.8 mm) to 21.6" (548 mm). The maximum operating speed is 64 carrier revolutions per minute, and the minimum is 40 carrier revolutions per minute. The braiding machine is equipped with an automatic lubricator for the track assembly. The machine is also equipped with a solid-state yarn depletion detection device, which can automatically turn off the machine in the event of yarn depletion or yarn breakage. The machine is equipped with a 40" (1,016 mm) capstan haul off designed for a maximum pull-off force of 400 lbs. (181.1 kg) and will accept a braiding diameter up to 2.0" (50.8 mm). The overall dimensions of the Model 36-V are 73.25 inches wide x 87.5 inches deep x 96.25 inches high (1,860.5 mm x 2,222.5 mm x 2,444.7 mm). It is equipped with four change gears, two braiding point dies, a complete set of carrier tension springs and a capstan pressure roll. The weight for this braiding machine is 3,500 lbs. (1,591 kg). The braiding machine can be equipped with an auxiliary overhead haul off, a precision braider former, as well as a cam heater system for running treated yarns.

BW-5L bobbin wire winder

The Magnatech BW-5L bobbin winder is a supplementary machine lot the RB-2 rotary braider, 225-II shuttle type winder and WSW-III precision wire spiral winder. Because these machines can run at high speed with advanced design, high productivity, uniform wire stress and tensile, its advantages include the capability of winding up to 12 ends (24 ends with optional let-off fixtures) and three constant bobbin spindle speeds of 670, 1,000 or 1,250 rpm. It incorporates a positive infinitely-variable drive system, operator safety guards with electrical interlock, a recessed and completely enclosed control panel, a pre-determined feet or meter reset control and totalizer, wire breakage stop motion, double wheel equalizing/measuring system, an attachment for lubricating the wire, a positive wire guide (to point of lay or on the bobbin) and an electrical full bobbin safety stop motion. The standard winder can install 12 reel let-off fixtures, with each accommodating supply reels holding approximately 65 pounds of steel wire. The specifications for some other bobbin winders are listed in table 5.

The braiding machines' other properties and related data are seen in table 6.

Summary

Most of the rubber hose reinforcing machines have been reviewed, such as yarn and wire rotary braiders, wire-spiral winders, as well as related equipment, including bobbin winders made by Rockwell, Magnatech, Mayer Industrial, Karg, etc. Their development, history, machinery properties, features, advantages and their applications in the rubber hose industry were reviewed. The technology will be further improved as computer control, other advanced technologies and more advanced materials are applied in this field. They will have a good future as the rubber hose industry grows in the new century.

Table 1--RB-2 rotary braider

No. of carriers              16       20       24       36
Carrier rpm
  Yarn                      100       90       75       50
  Wire                       90       80       69       45
[m.sup.2] floor space
  Deck                      4.5      4.5      4.5      4.5
  Haul off                  1.3      1.3      1.3      1.3
kg gross wt.
  Deck                    3,061    3,198    3,352    4,205
  Haul off                1,497    1,497    1,497    1,497
Bobbin capacity
  Yarn, [cm.sup.3]        3,606    3,606    3,606    3,606
  Wire, kg                11.34    11.34    11.34    11.34
Carrier tension
  Yarn                            1.8 kg to 5.44 kg
                                  Up to 13.60 kg

Table 2--MR-11S maypole braiding machine

Deck                      16        20        24        36
                        carrier   carrier   carrier   carrier

Length (mm)               910       910       910      1,016
Width (mm)               1,496     1,496     1,496     2,166
Height (mm)              2,017     2,017     2,017     2,858
Weight (kg)              2,200     2,300     2,400     5,000
Centerline (mm)          1,264     1,264     1,264     1,575

Wire
  Package size          1,600 cu. cm. (98 cu. in.)
  Weight                9.1 kg (20 lbs.)
  Speed (rpm)           235-275 rotor
                        58.7-68.7 carrier/47-55 carrier/
                        39.1-45.8 carrier/26-30.5 carrier
Yarn
  Package size          3,800 cu. cm (233 cu. in.)
  Weight                2.15 kg (4.75 lbs.)
  Speed (rpm)           245-260 rotor
                        61-65 carrier/49-52 carrier/
                        40.8-43.3 carrier/27-28.8 carrier

Super pack size         4,900 cu. cm (300 cu. in.)
  Super pack weight     4.5 kg (10 lbs.)
  Speed (rpm)           235-250 rotor
                        58.7-62 carrier/47-50 carrier/
                        39.1-41.6 carrier/26-28 carrier

Carrier tension         19.6 to 133.4N (4.4-30 lbs.)
Electrical              230/460 volt, 60/50 Hz [+ or -] 10%
Enclosure (mm)
  Single deck        2,135 x 1,933 x 2,977 2,135 x 1,933 x 2,977
                     2,135 x 1,933 x 2,977 2,686 x 2,616 x 3,417
  Double deck        4,103 x 1,933 x 2,977 4,103 x 1,933 x
2,977
                     4,103 x 1,933 x 2,977 4,976 x 2,616 x 3,417
  Triple deck        6,236 x 1,933 x 2,977 6,236 x 1,933 x 2,977

Table 3--spiral angles of wire spiral hose for some hose manufacturers

Spiral        U.K             France           Italy
ply           BTR             Kleber          Pirelli
No.         Diameter         Diameter         Diameter
           25 mm x 4S       19 mm x 4S       19 mm x 4S

1         56[degrees]     52[degrees]50'   54[degrees]44'
2        56[degrees]30'   54[degrees]44'   54[degrees]44'
3         57[degrees]     54[degrees]44'    57[degrees]
4        57[degrees]30'   55[degrees]10'    57[degrees]
5
6

Spiral               Japan                     China
ply          Togawa           Tokai          S.R.D.R.P.
No.         Diameter         Diameter         Diameter
           25 mm x 6S       51 mm x 6S       19 mm x 4S

1        51[degrees]30'    52[degrees]     52[degrees]50'
2         52[degrees]     52[degrees]50'   54[degrees]44'
3        54[degrees]30'   54[degrees]40'   54[degrees]44'
4        54[degrees]30'   56[degrees]20'   55[degrees]20'
5         56[degrees]     56[degrees]40'
6        57[degrees]30'   57[degrees]30'

Table 4--group type and wire capacity for
WSW-III precision wire spiral winder

Bobbin assemblies   Wire capacity   Ends for every
 group type for       a bobbin        turntable
     3/group           7.0 kg             90
     4/group           5.0 kg            120
     5/group           3.7 kg            150

Table 5--specifications for some bobbin winders

                    Spindle speed         Ends for
                         rpm             winding up

BW-6a-1                 1,200                6
  Bobbin winder
BW-5L wire         670,1,000,1,250       Up to 12 or 24
  Bobbin winder                      with optional let
YBW-1 yarn          150 to 1,800          Up to 8
  Bobbin winder
BW-7 wire            520 meter/m      3 to 36 ends of
  Bobbin winder         2,500            0.2-0.6 mm

                     Floor space     Weight
                          mm           kg

BW-6a-1              851 x 1,549       662
  Bobbin winder
BW-5L wire          1,676 x 1,397     1,406
  Bobbin winder
YBW-1 yarn           1,321 x 495       263
  Bobbin winder
BW-7 wire           1,400 x 1,400      315
  Bobbin winder        x 1,890

Table 6--braiding machines' properties and related data for some
braiding machine manufacturers

Company                 Karg             Mayer       Wardwell
                        U.S.            MR-IIS            US.
                                          U.S.

                    Vertical        Horizontal       Vertical
                      rotary           maypole         rotary
                     braider           braider        braider
Carrier                24,36       16,20,24,36       12,16,24
Size for hose      1/16 to 1              16C:   12C: 3/16 to
(1/D) inch                         3/16 to 3/8         5/416,
                                     20C: 3/16           16C:
                                   to 3/8 24C:   3/16 to 3/8,
                                                         24C:
                                                  3/16 to 1/2
Productivity/         1.5 to         1 million         1.5 to
year               2 million                      2.5 million
Feet
Speed for             24C:70           16C: 56      12C: 150-
carrier               36C:55           20C: 45            200
rpm                                  24C: 37.5   16C: 95-160,
                                                  24C: 70-110
Tension for          1 to 10             Yarn:          Upper
carrier                              3.5 to 30     carrier: 4
pounds                            Wire: 3-5 to          Lower
                                         12-35     carrier: 6
Advantage               High   High speed, big    High speed,
                       speed   capacity, fewer    lower price
                                    components
Defect
                        More              More           More
                     mainte-       preparation    preparation
                       nance              time           time

Company              Magnatech      Magnatech         Spirka
                        225-II           RB-2        Germany
                          U.S.           U.S.

                    Horizontal     Horizontal     Horizontal
                        rotary         rotary         rotary
                       braider        braider        braider
Carrier               20,24,36          24,36    16,20,24,32
                                                    36,40,48
Size for hose             20C:           24C:     Hole diam:
(1/D) inch        3/16 to 3/8,    3/16 to 3/4    16, 20, 24:
                          24C:      36C: 3/16          70 mm
                  3/16 to 3/4,         to 1/4         32,36:
                          36C:                         75 mm
                   3/16 to 1/4
Productivity/        1 million      2 million    (feet/hour)
year                                             16C: 2,600,
                                                     20, 24C
Feet                                                   1,530
                                                     32,36C:
                                                       1,760
Speed for              20C: 45        24C: 60       16C: 120
carrier              24C: 37.5        36C: 40     20,24C: 70
rpm                    36C: 25                    32,36C: 40
                                                  40,48C: 30
Tension for         Wire: 5 to          Wire:     1.5 to 4.0
carrier                     35       10 to 30
pounds              Yarn: 3 to          Yarn:
                            10        4 to 12
Advantage                 High           High     High speed
                    speed, big     speed, big
                     capacity,       capacity
                      both for
                      yarn and
Defect                    wire
                    More spare      Expensive          Small
                   parts, high                  capacity for
                     technical                        bobbin
                       mainte-
                         nance

Company              Carter          Panjin
                       U.K.           China

                 Horizontal      Horizontal
                    maypole         maypole
                    braider         braider
Carrier         16,20,24,32           24,36
                36,46,60,64
Size for hose                    24C: 10 to
(1/D) inch                           31 mm,
                                 36C: 15 to
                                      45 mm
Productivity/          0.66          0.5 to
year                million       1 million
Feet
Speed for           24C: 25         24C: 16
carrier           36C: 16.7         36C: 10
rpm               46C: 12.5
Tension for        Up to 28    Wire: 2.5-17
carrier                                  kg
pounds                                Yarn:
                                 1.5-6.0 kg
Advantage        Many sizes     Lower price,
                for carrier     easy operat-
                                        ing
Defect
                      Small      High noise
               capacity for
                     bobbin

References

(1.) Taiwan Rubber Industry 1997, No. 12, pp. 39-46.

(2.) Magnatech Co. equipment manual 1996.

(3.) Rockwell Co. equipment manual 1986.

(4.) Mayer Industrial Co. products equipment manual 1988, 2000.

(5.) BTR Co. product manual 1990.

(6.) Kleber Co. product manual 1990.

(7.) Pirelli Co. product manual 1988.

(8.) Tokai Co. product manual 1990.

(9.) Karg Co. equipment manual 1988.

(10.) Panjin Rubber & Plastic Machinery Plant, product manual 1988, 1998.