BUILDING

STRENGTH

CONCRETE PRESTRESSING
PRODUCT HANDBOOK

D A Y T O N S U P E R I O R . C O M

Prestress Strand Restraining Devices

The following is taken from the Prestressed Concrete Institute Manual for Quality Control for Plants and Production of Precast/Prestressed Concrete Products, and relates to certain safety requirements. Precast/ prestressers are urged to refer to the manual for a thorough understanding of all aspects of quality control during the prestressing process.

Section 2 Safety
4.2.1 General Considerations
The large tensioning forces which are necessary in all prestressing operations inevitably result in such construction being very hazardous. The Prestressed Concrete Institute has an in-depth PCI Safety and Loss Prevention Manual program. It outlines general safety practices as it relates to the prestressing industry and existing Federal regulations. Each prestressing plant and each employee in the plant shall be required to comply with the PCI safety and Loss Prevention Manual. The purpose of this section is to outline some of the more important safety measures particularly applicable to prestressing plants. The potential hazards discussed in this section are generally understood by producers and workmen alike; however, it is human nature that people who are constantly exposed to potentially dangerous situations tend over a period of time to lose their conscious fear unless they are constantly reminded of the danger. It shall be the responsibility of the supervisory personnel to insure safety is never subordinated to personal apathy or production expediency. Any employee who will not abide by prescribed safety rules shall not be permitted to work in a prestressing plant. The most important consideration, which should be kept in mind by all levels of personnel in prestressed concrete plants, is tendons under tension as high as 190,000 psi (1,300 MPa) represent energy which, upon sudden release, can have serious results. This is a condition peculiar to the manufacture of prestressed concrete and must be constantly recognized and planned for if a good safety record is to be established. This section is intended to outline safety practices for prestressed concrete plants in a broad manner and cannot be considered to include every conceivable hazard that may be present in a prestressed concrete plant; however, the recognition of hazards, the establishment of good safety practices and the requirement that all personnel abide by safety rules will result in a more efficient and safer operation in any plant.
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Dayton Superior Strand Restraining Devices

Prestress Strand Restraining Devices

Dayton Superior Strand Restraining Devices

Prestress Strand Restraining Devices

4.2.2 Safety Measures for All Tensioning Operations
The operation of tensioning has more potential for serious accidents than all other phases of prestressed concrete production combined. The following basic rules applicable to tensioning shall be included in the safety requirements of all plants: (1) Prior to tensioning any bed, a visible and audible signal shall be given and all personnel not required to perform the tensioning shall leave the area adjacent to the bed. (2) Jacks shall be held by means preventing the jack from flying longitudinally or laterally in case of tendon failure. (3) Personnel shall never be permitted to stand at either end of the bed, directly in line with the tendon being tensioned. (4) Personnel shall not stand over tendons being tensioned to make elongation measurements. Such measurements shall be preferably be made by jigs or templates from the side or from behind shields. (5) For personnel engaged in the tensioning operation, protection shall be provided by means of effective shields adequate to stop a flying tendon. These shields should be provided at both ends of the bed and should be of reinforced concrete or heavy timbers. Shields of wire mesh are not satisfactory as broken strands often fly end first and may penetrate the wire openings. (6) Eye protection shall be provided for personnel engaged in wedging and anchoring operations as a protection from flying pieces of steel.

4.2.3. Safety Measures for Pretensioning

Principal causes and remedies for tendon failure during pretensioning include the following: (1) Defective or improper strand vises: Clean, inspect and lubricate strand vises between each use. Use of at least a threepower illuminated magnifying glass for inspecting strand vises is recommended. Discard any worn or distorted chucks. A small amount of sand or dirt between chucks and the barrel can cause failure or slippage of the strand. (2) Improper alignment of strand vises: See that vises are in line with pull and are seated normally. (3) Overstressing: Check elongation and keep tension-indicating devices properly calibrated. (4) Kinks or nicks in strand: Use care in handling strand to avoid damage. Do not begin tensioning if a strand has been nicked. (5) Failure of individual wires in strand: These often occur in factory welds and cannot be avoided. Do not tension any strand with a broken wire. (6) Heating of a tensioned strand: Keep all torches and welding equipment away from tensioned strand. (7) Sudden multiple revolutions of strand being pulled from a coil: Use approved swivel grips or other effective methods. (8) Local overstress due to friction in tensioning of draped strands: For strands tensioned in the draped position, use roller bearings at all hold-down and support points. Before placing concrete, the bearings within the members can be replaced with less expensive devices. For strands tensioned in a straight line and subsequently deflected, do all deflecting simultaneously or on a predetermined schedule symmetrically about the center of the bed.

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Prestress Strand Restraining Devices

Since 1958 Dayton Superior has been working closely with prestressed concrete producers to develop and patent a most comprehensive line of restraining devices. The various designs are available to meet the many applications found in todays prestressed concrete industry. With Dayton Superior quality engineered and manufactured strand restraining devices deflecting part of the prestressing tendons a more favorable distribution of stresses within the prestressed beam can be obtained. The reduced tensile stresses at the concrete beams ends can increase the load carrying capacity of the beam by amounts equal to the weight of the beam itself.
Spacer Strand Restrainer Bushings Free Turning Strand Roller Lock Nut

Hi-Strength Roller Bolts Retainer Ring Coil Threaded Swivel Lug

Exploded View of a Typical Strand Restraining Device

Typical Application of a Strand Restraining Device

Warning: Safe construction practice requires that all strand retaining device instructions, safe working loads and warnings/cautions be followed. Strand retaining devices are designed for a one-time use only. Using a unit as a hold-up and then reusing it as either a hold-up or hold-down may result in an unexpected failure.

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Dayton Superior Strand Restraining Devices

Prestress Strand Restraining Devices

Strand Restraining Devices

Dayton Superior

Prestress Strand Restraining Devices

Hold-up Applications
When strand retaining devices are to be used as hold-up units, it is critical that a qualified person verify the loads that will be applied. Generally, the loads at hold-up points will be twice the loads that are to be applied to the hold-down units and require the use of two strand retaining devices to meet the safe working load requirements. Dayton Superior recommends that hold-up units be spaced at least 18 (450 mm) apart. Warning: When strand retaining devices are used as a hold-up unit, they should be used only one time and then discarded. Reuse can
result in fatigue and wear and result in unexpected failures. Dayton Superior does not recommend using a strand restraining device more than one time.

Typical Hold-up Restraining Application

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How To Calculate Uplift Loads On Strand Restraining Devices

Hold-Up 18 (450 mm) Minimum Hold-Up

Bulkhead

H v

Pu
Beam

Pu

Pu
Beam

Pu

Gu

Hold-Down

Gu Pu = H
v h

Gu or Gu = H
v h

Gu

Pu Gu H V h HDF HDF

= Uplift load per strand = Load per strand at intermediate hold-up point = Horizontal pull = Amount of strand deflection = Distance from hold-up to hold-down = Total hold-down force (Pu) x (Number of strands) = Total hold-up force (Gu) x (Number of strands)

Example: Pu = H v
h

H = 28,900 lbs. (128.5 kN) V = 3-0 (914 mm) h = 30-0 (9,000 mm) Pu = 28,900 (128.5 kN) x 3-0 (914 mm) 30-0 (9,000 mm)

Example: Assume 6 strands at hold-down and hold-up positions and that swivel units will be used. HDF = (6 strands) x [2,890 lbs. (12.8 kN) per strand x 1.05 friction loss] HDF = 18,207 lbs. (80.9 kN) Use any swivel unit that satisfies strand pattern, individual SWL per strand and SWL for unit.

*Pu = 2,890 lbs. (12.8 kN) per strand *Gu = 2,890 lbs. (12.8 kN) per strand *Total uplift load per strand should be determined by adding a percentage increase for friction losses (Add 5% friction loss for swivel units and 15% friction loss for nonswivel units).

Warning: Safe construction practice requires that all strand retaining device instructions, safe working loads and warnings/cautions be
followed. Strand retaining devices are designed for a one-time use only. Using a unit as a hold-up and then reusing it as either a hold-up or hold-down may result in an unexpected failure.

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Strand Restraining Devices

Dayton Superior

Prestress Strand Restraining Devices

Dayton Superior Strand Restraining Devices

Prestress Strand Restraining Devices

General Strand Restraining Device Notes:
1. Safe working loads shown in this publication provide a factor of safety of approximately 1.5:1. 2. Safe working loads should be determined by calculating the upward forces and adding a percentage increase for friction losses. (Add 5% friction for swivel units and 15% for non-swivel units). 3. Strand restraining devices are rated by uplift per strand as well as total uplift per unit. Care must be taken to see that neither rating is exceeded. 4. Maximum number of strands per unit is determined by dividing the maximum safe working load per unit by the actual strand load plus friction losses. 5. When H-53 Strand Restraining Devices are required: A. With one through four strands, the device will be supplied with single side frames. B. With five or more strands, the device will be supplied with double side frames and heat treated lugs. 6. When H-40 units are required: A. With one through three strands, the device will be supplied with single side frames. B. With four or more strands, the device will be supplied with double side frames and heat treated lugs. 7. H-41, H-41-R, H-56, H-56-R or H-56-S units are supplied with double side frames and heat treated lugs. 8. Any unit with a B dimension of 6 (150 mm) or greater will be supplied with a Spacer Bolt and Nut above the swivel lug.

Stressing Notes:
A. All strand restraining devices should be loaded (stressed) in descending order from top strand(s) down to lower strand(s). B. Two vertical strand restraining devices should be loaded by stressing alternating strands. Loading more than one strand per side at one time will cause unbalanced loading that may result in premature failure of the unit. C. Three vertical row strand restraining devices should be loaded by stressing the center row first, then alternating the outside rows in a symmetrical manner. Failure to do so may result in a premature failure of the unit.

Bottom of Bed

H-65-R Unit

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H-2 Strand Clamp

Used to position and hold bulkheads during concrete placement. For use with 1/2 (13 mm) and 0.6" (15 mm) diameter strands. Special thread is not affected by vibrating operations. Replacement screws are available on request.

To Order:
Specify: (1) quantity, (2) name

H-2 Strand Clamp

#56220 - 1/2" #128577 - 0.6"

Example:
50, H-2 Strand Clamps.

H-15 Multi-Strand Push-Down Anchor

Used to depress 1/2 (13 mm) diameter strand in a single row. Used in double tees, channel slabs and similar prestressed elements requiring moderate strand deflection. Through hole in casting accepts a 3/4 (19 mm) diameter stem pin that must protrude through the hole and be in contact with the strand. The stem pins end is chamfered to prevent strand damage. Notes: Safe working loads have not been assigned to this product due to the variable methods used to depress the strands. Tests indicate that high vertical loads are maintained when the strands remain vertical and do not override one another. Overriding strands may cause the open end of the anchor to spread. Effective use of the H-15 anchor depends on proper pin diameter, maintaining vertical plumb and having minimal strand override. The H-15 anchor is not recommended for use with threaded pushdown rods.
3-1/8 4-1/8 5-5/8 H-15 #3 1 to 3 Strand #56003

H-15 #5 4 & 5 Strand #56005 H-15 #8 6 to 8 Strand #56008

H-15 Multi-Strand Push-Down Anchors

To Order:
Specify: (1) quantity, (2) name, (3) size

Example:
200, H-15 Multi-Strand Push-Down Anchors, #5 size.

Taper Push Down Rod By Others 3/4 o Stem Pin x 1-11/16 By Others

H-15 #5

H-15 Multi-Strand Push-Down Anchor Typical Application

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Strand Restraining Devices

Dayton Superior

Prestress Strand Restraining Devices

Dayton Superior Strand Restraining Devices

Prestress Strand Restraining Devices

H-21 Strand Restraining Device
Specifications:
High Strength Coil Rod Diameter 3/4 (19 mm). Max. safe working load per strand 3,000 lbs. (13.3 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) See Note 3 on Page 8. (A) Horizontal spacing Not applicable. (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 2-3/8 (60 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.
C C D

H-24 Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 3/4 (19 mm). Max. safe working load per strand 6,000 lbs. (26.6 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) See Note 3 on Page 8. (A) Horizontal spacing 2.0 (50 mm). (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 3-7/8 (98 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.
C D A

H-23 Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 3/4 (19 mm). Max. safe working load per strand 8,000 lbs. (35.4 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) See Note 3 on Page 8. (A) Horizontal spacing Not applicable. (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 2-3/8 (60 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.
C C

H-24-R Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 3/4 (19 mm). Max. safe working load per strand 6,000 lbs. (26.6 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) See Note 3 on Page 8. (A) Horizontal spacing 2.0 (50 mm).
B D A

(B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 3-7/8 (98 mm).

Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.

To Order Strand Restraining Devices:

Specify: (1) quantity, (2) name

Example:
500, H-21 Strand Restraining Devices.
10 4-09

H-25* Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 3/4 (19 mm). Max. safe working load per strand 7,500 lbs. (33.3 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) See Note 3 on Page 8. (A) Horizontal spacing 2.0 (50 mm). (B) Min. vertical spacing (form to centerline of first strand) Not applicable. (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 3-7/8 (98 mm).
D D A

H-25-S Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 3/4 (19 mm). Max. safe working load per strand 7,500 lbs. (33.3 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) See Note 3 on Page 8. (A) Horizontal spacing 2.0 (50 mm). (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 3-7/8 (98 mm).
D A

Warning: Safe working load B displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts. *Patented unit.

Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.

H-25-R* Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 3/4 (19 mm). Max. safe working load per D strand 7,500 lbs. (33.3 kN) See Note 3 on Page 8. A Max. safe working load per unit 24,000 lbs. (106.0 kN) See Note 3 on Page 8. (A) Horizontal spacing 2.0 (50 mm). (B) Min. vertical spacing (form to centerline of first C strand) Not applicable. (C) Standard vertical spacing 2.0 (50 mm). C (D) Overall width 3-7/8 (98 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts. *Patented unit.
C

H-26 Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 6,000 lbs. (26.6 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) See Note 3 on Page 8. (A) Horizontal spacing 2-3/16 (55 mm). (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 3-7/8 (98 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.
D A

To Order Strand Restraining Devices:

Specify: (1) quantity, (2) name

Example:
500, H-25-S Strand Restraining Devices.
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Dayton Superior Strand Restraining Devices

Prestress Strand Restraining Devices

Dayton Superior Strand Restraining Devices

Prestress Strand Restraining Devices

H-26-R Strand Restraining Device
Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 6,000 lbs. (26.6 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) See Note 3 on Page 8. (A) Horizontal spacing 2-3/16 (55 mm). (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 3-7/8 (98 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.
C D A

H-41 Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 6,000 lbs. (26.6 kN) See Note 3 on Page 8. Max. safe working load per unit 40,000 lbs. (177.9 kN) See Note 7 on Page 8. (A) Horizontal spacing 2-1/2 (63 mm). (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 4-3/8 (111 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.
C D A

H-40 Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 8,000 lbs. (35.4 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) or 40,000 lbs. (177.9 kN) See Note 6 on Page 8. (A) Horizontal spacing Not applicable. (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (D) Overall width 2-7/8 (73 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.
C

H-41-R Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 6,500 lbs. (28.8 kN) See Note 3 on Page 8. Max. safe working load per unit 40,000 lbs. (177.9 kN) See Note 7 on Page 8. (A) Horizontal spacing 2-1/2 (63 mm). (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 4-3/8 (111 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.
C D A

(C) Standard vertical spacing 2.0 (50 mm).

To Order Strand Restraining Devices:

Specify: (1) quantity, (2) name

Example:
500, H-41 Strand Restraining Devices.
12 4-09

H-42 Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 8,000 lbs. (35.4 kN) See Note 3 on Page 8. Max. safe working load per unit 42,000 lbs. (186.8 kN) See Note 3 on Page 8. (A) Horizontal spacing 2.0 (50 mm). (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2/0 (50 mm). (D) Overall width 3-7/8 (98 mm).
D A

H-53 Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 6,000 lbs. (26.6 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) or 48,000 lbs. (212.0 kN) See Note 5 on Page 8. (A) Horizontal spacing Not applicable. (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 3-3/8 (92 mm).
D

Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.

Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.

H-42-R Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 8,000 lbs. (35.4 kN) See Note 3 on Page 8. Max. safe working load per unit 42,000 lbs. (186.8 kN) See Note 3 on Page 8. (A) Horizontal spacing 2.0 (50). (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 3-7/8 (98 mm).
D A

H-55 Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 4,000 lbs. (17.7 kN) See Note 3 on Page 8. Max. safe working load per unit 48,000 lbs. (212.0 kN) See Note 3 on Page 8. (A) Horizontal spacing 2.0 (50mm). (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 6-7/8 (174.6 mm).
D A A

B Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.

Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.

To Order Strand Restraining Devices:

Specify: (1) quantity, (2) name

Example:
500, H-55 Strand Restraining Devices.
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Strand Restraining Devices

Dayton Superior

Prestress Strand Restraining Devices

Dayton Superior Strand Restraining Devices

Prestress Strand Restraining Devices

H-55-R Strand Restraining Device
Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 4,000 lbs. (17.7 kN) See Note 3 on Page 8. C Max. safe working load per unit 48,000 lbs. (212.0 kN) See Note 3 C on Page 8. (A) Horizontal spacing 2.0 (50 mm). C (B) Min. vertical spacing (form to centerline of first strand) 2.0 (50 B mm). (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 6-7/8 (174.6 mm).
D A A

H-56-R Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 7,500 lbs. (33.3 kN) See Note 3 on Page 8. Max. safe working load per unit 24,000 lbs. (106.0 kN) or 48,000 lbs. (212.0 kN) See Note 7 on Page 8. (A) Horizontal spacing 2.0 (50 mm). (B) Min. vertical spacing (form to centerline of first strand) Not applicable. (C) Standard vertical spacing 2.0 (50 mm). (D) Overall width 4-3/8 (111 mm).
D A

Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.

3/4

Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.

H-56-S Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 7,500 lbs. (33.3 kN) See Note 3 on Page 8. Max. safe working load per D unit 24,000 lbs. (106.0 A kN) or 48,000 lbs. (212.0 kN) See Note 7 on Page 8. (A) Horizontal spacing 2.0 (50 mm). (B) Min. vertical spacing (form to centerline of first C strand) 2.0 (50 mm). (C) Standard vertical C spacing 2.0 (50 mm). (D) Overall width 4-3/8 (111 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.
C

H-56 Strand Restraining Device

Specifications:
High Strength Coil Rod Diameter 1.0 (25 mm). Max. safe working load per strand 7,500 lbs. (33.3 kN) See Note 3 on Page 8. D Max. safe working load per A unit 24,000 lbs. (106.0 kN) or 48,000 lbs. (212.0 kN) See Note 7 on Page 8. (A) Horizontal spacing 2.0 (50 mm). (B) Min. vertical spacing C (form to centerline of first strand) Not applicable. (C) Standard vertical spacing 2.0 (50 mm). C (D) Overall width 4-3/8 (111 mm).
Warning: Safe working load displayed can only be achieved by utilizing Dayton Superior B-12 High Strength Coil Rod and B-25 Heavy Coil Nuts.
C

To Order:
Specify: (1) quantity, (2) name

Example:
500, H-56 R Strand Strand Restraining Devices
14 4-09

Special Custom Units

Many special or custom variations of strand restraining devices are available. The interchangeability of Dayton Superior designs and individual parts allow for great flexibility and economy in the fabrication of specials.

Special Heavy Duty Unit

Special Triple Row Unit

Special Stacked Strand Unit

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15

Strand Restraining Devices

Dayton Superior

Prestress Strand Restraining Devices

Notes

16

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CCL Stressing Systems

Stressing Systems For Concrete Construction

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17

CCL Stressing Systems for Concrete Construction

CCL Stressing Systems

CCL Stressing Systems

CCL Stressing Systems for Concrete Construction

Quality Assurance
CCL Stressing Systems provides technical assistance with the selection of appropriate products for precast concrete. A well staffed and trained technical department will be pleased to discuss specific applications. CCL Stressing Systems products are designed to the quality requirements of BS ISO 9001.

CCL Stressing Systems has long been dedicated to the design and manufacture of quality equipment for prestressing concrete. This dedication has produced a state-of-the-art product line accepted as the industry leader throughout the world. In an effort to provide the most reliable products available, each product component is tested individually. The chuck barrels are checked with ultra violet lights for cracks and/or imperfections. Each wedge is scanned by laser to determine acceptability and then checked visually for defects. Finally, after heat treating, the wedges are tested for core hardness and ductility. Hydraulic equipment undergoes equally rigorous testing procedures to ensure that the products will perform to the excellence implied by the CCL Stressing Systems name.

Prestressing Products
CCL Stressing Systems range of prestressing products includes Jacks and Pumps, Open Chucks, Spring Loaded Anchors and Double Ended Joints. Spring Loaded Anchors are available as either bayonet cap or threaded cap type anchors. The bayonet cap provides a quick release mechanism to facilitate cleaning and maintenance. When stressing beds are partially empty, Double Ended Joints can be used to connect two lengths of wire or strand in order to reduce waste. They are also used to create reducing joints by joining strands of different sizes.

Post Tension Refurbishment

The single-strand line of CCL Stressing Systems Jacks can be used for the refurbishment of post-tensioning systems. In conjunction with the Double-Ended Joints, both bonded and un-bonded systems can be repaired using the standard system available for prestressed/ precast concrete.

18

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CCL Stressing Systems

H-60-A Spring Loaded Anchors

Spring Loaded Anchors should always be used at the non-stressing end of the bed. They promote correct seating of the wedges and prevent them from being dislodged from the barrel at the non-stressing end while preparation work is carried out at the stressing end. However, if using a jack without power lock-off to carry out the prestressing operation, Spring Loaded Anchors must be used at the stressing end of the bed, also. Two kinds of Spring Loaded Anchors are available: one features a bayonet cap and the other a threaded cap. Both models incorporate the same wedge as the Open Chuck, but have longer barrels and a spring. A double ended joint can be created by joining two threaded cap anchors with a center plug. The strand chucks are sold in the bayonet style, while the wire chucks are sold in the threaded style. H-60-A XL2 Wire Threaded Cap Chuck The bayonet cap anchor has a quick release Wire (mm) 4 5 5.25 6 feature that allows for easy cleaning and inspection operations. Outside diameter (mm) d 25 25 25 25
Safety Note: Always use spring loaded anchors at the non-stressing end of the bed. If using a jack without power lock-off, spring loaded anchors should also be used at the stressing end of the bed. Outside diameter (in) d Length (mm) Length (in) Chuck Weight (lb) Complete Chuck Code Barrel Code Wedge Code l l 1 66 2.64 14,400 0.61 603601 603520 603701 1 66 2.64 14,400 0.61 603603 603520 6036703 1 66 2.64 14,400 0.61 603602 603520 603714 1 66 2.64 14,400 0.61 603604 603520 603704 CCL Stressing Systems for Concrete Construction

7
25 1 66 2.64 14,400 0.61 603605 603520 603705

To Order: Specify: (1) quantity, (2) description, (3) product code. Example: 200, H-60-A CCL Stressing Systems Spring Loaded Anchors with 5 mm XL2 Wire Threaded Cap Chuck, 603603.
l

Maximum Barrel Load (lbs)

These are maximum barrel loads. For strand/wire ratings contact your supplier. Refer to full safety instructions included with each pack of CCL Stressing System Chucks.

Strand Bayonet Chuck

Wire Threaded Chuck

H-60-A XLX Strand Bayonet Chuck 1/2 13
44 1.76 88 3.52 47,025 1.66 604024 604124 604204

H-60-A XL Strand Bayonet Chuck Strand (in) Strand (mm)

Outside diameter (mm) Outside diameter (in) Length (mm) Length (in) Chuck Weight (lb) Complete Chuck Code Barrel Code Wedge Code d d l l

5/16 8
35 1.4 84 3.36 22,950 0.85 604081 604132 604201

3/8 9.6
35 1.4 84 3.36 22,950 0.85 604068 604132 604202

7/16 11
40 1.6 77 3.08 31,275 1.21 604023 604123 604203

0.6 15
50 2 109 4.36 67,500 2.42 604049 604129 604225

3/8 (7/16 form) 7/16 (1/2 form) 9.6 (11 form)

40 1.6 77 3.08 31,275 1.21 604026XLX 604123 604245

11 (13 form)
44 1.76 88 3.52 47,025 1.66 604027XLX 604124 604246

Maximum Barrel Load (lbs)

These are maximum barrel loads. For strand/wire ratings contact your supplier. Refer to full safety instructions included with each pack of CCL Stressing System Chucks.

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19

CCL Stressing Systems

H-60-B Open Chucks

CCL Stressing Systems for Concrete Construction

CCL Stressing Systems Open Chucks are the most popular multi-functional chucks in use worldwide. The Open Chuck is comprised of a wedge contained within a barrel. The wedge is manufactured in two segments for prestressing applications using wire and in three segments for strand stressing applications. AnO ring is used to hold the segments of the wedge together.
l

H-60-B XL2 Wire Open Chuck Wire (mm)

Outside diameter (in) Length (in) Maximum Barrel Load (lbs) Chuck Weight (lb)

4
0.96 1.08 14,400 0.20 603001 603510 603701

5
0.96 1.08 14,400 0.20 603003 603510 603703

5.25
0.96 1.08 14,400 0.20 603002 603510 603714

6
0.96 1.08 14,400 0.20 603004 603510 603704

7
0.96 1.08 14,400 0.20 603005 603510 603705

Open Chuck

The design of the Open Chuck enabled the user Complete Chuck Code to check the position of the wedge during use. Throughout the detensioning stage the Open Chuck Barrel Code is easily accessible. Wedge Code The Open Chuck is cost effective and is easily cleaned and maintained.

Safety Note: Dayton Superior strongly recommends that open grips only be used with a hydraulic jack that has a power lockoff mechanism. This ensures that the load is born by the jack while the wedges are correctly positioned. The wedges are then locked off while the strand remains in tension. Spring loaded anchors with either threaded or bayonet caps should always be used at the non-stressing end of the bed or when using a jack without a power lock-off mechanism.

The maximum barrel loads referenced above refer only to the chuck. For strand/ wire ratings please contact your supplier. Please refer to full safety instructions included with each pack of CCL Stressing System grips.

To Order:
Specify: (1) quantity, (2) description, (3) product code.

Example:
200, H-60-B CCL Stressing Systems 7/16 XL Strand Open Chuck, 604003.

H-60-B XL Strand Open Chuck Strand (in) Strand (mm)

Outside diameter (mm) Outside diameter (in) Length (mm) Length (in) Maximum Barrel Load (lbs) Chuck Weight (lb) Complete Chuck Code Barrel Code Wedge Code

H-60-B XLX Strand Open Chuck 1/2 13

44 1.76 47 1.88

5/16 8
35 1.4 36 1.44 22,950 0.58 604001 604101 604201

3/8 9.6
35 1.4 36 1.44 22,950 0.56 604002 604101 604202

7/16 11
40 1.6 45 1.8 31,275 0.92 604003 604103 604203

.6 15
50 2 57 2.28 67,500 1.76 604071 604145 604225

3/4 18
60 2.4 72 2.88 85,500 3.22 604006 604106 604206

3/8 (7/16 form) 7/16 (1/2 form) 9.6 (11 form)

40 1.6 45 1.8 31,275 0.92 604045XLX 604103 604245

11 (13 form)
44 1.76 47 1.88 47,025 1.17 604043XLX 604104 604246

47,025 1.17 604004 604104 604204

The maximum barrel loads referenced above refer only to the chuck. For strand/wire ratings please contact your supplier. Please refer to full safety instructions included with each pack of CCL Stressing System grips.

20

4-09

CCL Stressing Systems

H-60-C Double Ended Strand Joints
Double Ended Strand Joints consist of two barrels joined by means of a hexagonal center plug. Both of the chamfered ends and the hexagonal center plugs incorporate wrench flats to facilitate quick and easy assembly. The Double Ended Joint also features safety pegs to ensure that the wedge and strand are fully engaged. Use of Double Ended Joints provides various costs savings, i.e., reducing waste, connecting different sizes of strands (reducing joint) and permits the use of one size jack head, nose and wedge when using more than one size of strands in a concrete unit.
Safety Note: When a reducing joint is formed, the prestressing force must be reduced to that of the smallest strand. CCL Stressing Systems for Concrete Construction

Double Ended Joint

l

Joint Reducer
l

To Order:
Specify: (1) quantity, (2) description (3) product code

Example:
d 200, H-60-C CCL Stressing Systems 7/16" XL2 Strand Double Ended Joints, 604065

H-60-D XL2 Wire Double Ended Joints Wire (mm) Wire (in)
Outside diameter (in) Length (in) Chuck Weight (lb) Complete Chuck Code Barrel Code Wedge Code Plug Code Spring Code d l

Joint Reducer 6 0.24

0.96 4.72 14,400 0.80 603654 603510 603704 603340 603420

4 0.16
0.96 4.72 14,400 0.80 603651 603510 603701 603340 603420

5 0.20
0.96 4.72 14,400 0.80 603653 603510 603703 603340 603420

5.25 0.21
0.96 4.72 14,400 0.80 603652 603510 603714 603340 603420

7 0.28
0.96 4.72 14,400 0.80 603655 603510 603705 603340 603420

Strands To Be Spliced
3/8 - 5mm 3/8 - 7mm 1/2 - 3/8 1/2 - 7/16 .6 - 1/2

Plug Code
603345 603345 604357 604356 604355

Maximum* Barrel Load (lbs)

The maximum barrel loads referenced above refer only to the chuck. For strand/wire ratings please contact your supplier. Please refer to full safety instructions included with each pack of CCL Stressing System grips. 4-09 21

CCL Stressing Systems

H-60-D Double Ended Wire Joints

CCL Stressing Systems for Concrete Construction

In some situations it may be necessary to connect two lengths of wire together. CCL Stressing Systems Double Ended Joints can be used to accomplish this task. Double Ended Joints consist of two tapered barrels each containing a wedge and spring. The two are joined by a knurled center plug. A simple and safe assembly. The chamfered ends of the joints are designed to help reduce the likelihood of two joints becoming trapped against one another during prestressing operations.

To Order:
Specify: (1) quantity, (2) description, (3) product code.

Example:
200, H-60-D CCL Stressing Systems 5 mm XL2 Wire Double Ended Joints, 603653.

Wire Double Ended Joint

H-60-D XL2 Wire Double Ended Joints Wire (mm) Wire (in)
Outside diameter (in) Length (in) Chuck Weight (lb) Complete Chuck Code Barrel Code Wedge Code Plug Code Spring Code d l

4 0.16
0.96 4.72 14,400 0.80 603651 603510 603701 603340 603420

5 0.20
0.96 4.72 14,400 0.80 603653 603510 603703 603340 603420

5.25 0.21
0.96 4.72 14,400 0.80 603652 603510 603714 603340 603420

6 0.24
0.96 4.72 14,400 0.80 603654 603510 603704 603340 603420

7 0.28
0.96 4.72 14,400 0.80 603655 603510 603705 603340 603420

Maximum* Barrel Load (lbs)

These are maximum barrel loads. For strand/wire ratings contact your supplier. Refer to full safety instructions included with each pack of CCL Stressing System Chucks. 22 4-09

CCL Stressing Systems

H-64 Stressomatic Prestressing Jacks

CCL Stressing Systems quality engineered jacks provide accurate and reliable prestressing. Durable construction and hardwearing seals contribute to an extended service life. The location of the pulling wedges close to the jacks nose allows attachment to be made with only a short length of the wire or strand. As the jack extends, the strand is grasped automatically. When retraction is complete, the strand is released. This extension and retraction is carried out rapidly. Any length of strand can be prestressed. All CCL Prestressing Jacks incorporate a power lock-off safety feature that ensures the wedges are correctly seated and prevents the release of the strand under load. See additional information about the power lock-off below. All jacks are designed to be stripped down quickly and easily for cleaning and maintenance. Tools are provided for this purpose. CCL Prestressing Jacks are available in three sizes capable of delivering maximum forces of 13,500 lbs., 36,000 lbs. and 54,000 lbs., respectively. Jack specifications are shown in the accompanying table. Long stroke versions of the 36,000 lbs. and 54,000 lbf jacks are also available.
CCL Stressing Systems for Concrete Construction

H-64 Stressomatic Jacks Jack Size

Maximum Force (lbs) Wire Diameters (mm) Strand Diameters (in) Stroke (in) Weight (lbs) Closed Length (in)

Type 60 Type 160 Type 160L Type 300 Type 300L

13,500 4-7 8 31.0 25.4 36,000 8 63.8 29.0 36,000 20 77.0 42.2 54,000 1/2 - 3/4 8 99.0 28.9 54,000 1/2 - 3/4 16.5 112.2 37.2

5/16 - 1/2 5/16 - 1/2

Optional Force Control System

An optional force control system is available to provide a more accurate and consistent prestressing force. The required force is entered into the computer and can be fixed to prevent operator error. The output is delivered via a multi-trip meter that provides a direct reading of the force applied. The force control unit gives a choice of trip positions that can be used for the full prestressing force and to stop the jack at intermediate force positions. A printout showing results can also be obtained. The prestressing system is designed to identify when the force control option is in use. In the event of computer failure or disconnection, it can be switched to manual operation.
Safety Note: CCL Stressing Systems Stressomatic Jacks are operated by means of a remote push button control box. This allows the operator to carry out the prestressing operation while standing at a safe distance from the jack.

Power Lock-Off Feature

In order to ensure that anchoring chucks are correctly seated on the strand, CCL jacks incorporate a power lockoff mechanism. This important safety feature minimizes the risk of the strand being released when the jack is retracted. 1. The strand or wire is tensioned. The load is being held by the prestressing jack. The wedges are in position prior to lock-off. 2. The piston moves forward locking off the wedges while the strand or wire remains under tension. This design allows for the use of open grips that are much less expensive than spring loaded anchors.

To Order:
Specify: (1) quantity, (2) name, (3) type.

Example:
12, H-64 Stressomatic Prestressing Jacks, Type 160.

4-09

23

CCL Stressing Systems

H-66 Prestressing Pumps

CCL Stressing Systems for Concrete Construction

CCL Prestressing Systems pump unit (Series 3000), will operate any CCL jack head. The pumps modular design facilitates service and maintenance operations and their durable construction affords excellent job site protection. Pump specifications are shown in the table below. Standard electric motors are available to suit 110 VAC, 220/240 VAC and 380/415 VAC, 3 phase (50 or 60 Hz). A six inch pressure gauge is fitted to provide an alternate method of measuring force. A digital pressure gauge is available as optional equipment all pumps are fitted with high quality 9-3/4 hoses that incorporate quick release couplings to enable jack heads to be switched quickly. The dolly is all steel with side cradles to accommodate the jacks when not in use. A steel protective frame is also available.

Pump Delivery And Maximum Pump Pressure

The Series 3000 Pump delivers hydraulic oil at a rate of 1.67 gallons per minute to an adjustable maximum pressure of 5,000 psi, then at 0.55 gallons per minute to 8,000 psi.
a

SR 3000 Series Pump Unit

b

d/e

Pump Specifications and Dimensions Jack/Pump Speeds (in/s) Jack Type

SR3000 Pump Up to Changeover Pressure SR3000 Pump After Changeover Pressure

Pump 300
0.80

SR3000
8.45 352 a b c d 42.0 26.5 20.8 39.4 33.6

60
2.20

160
1.22

160L
1.22

300L
0.80

Oil Reservoir (gallons) Pump Weight* (lbs) Maximum Length (in) Maximum Width (in) Axle Width (in) Height With Frame (in)

0.84

0.44

0.44

0.31

0.31

*Speeds quoted are extend speeds

Height Without Frame (in) e *Weight includes trolley, oil and frame

To Order:
Specify: (1) quantity, (2) name, (3) series.

Example:
2, H-66 CCL Prestressing Pumps, Series 3000.

24

4-09

CCL Stressing Systems

Prestressing Accessories
A comprehensive group of prestressing accessories are available for use with CCL Stressing Systems prestressing products.

Chuck Lubricant
CCL Stressing Systems for Concrete Construction 25

Calibration Control Unit

The calibration Control Unit can be used with all CCL jacks to calibrate the system. It features a clear digital readout and rechargeable battery.

To ensure chuck performance, easy release and maximum length of service, they should be regularly submerged in Super Dippy lubricant between uses.

Detensioning Noses
A range of detensioning noses are available for use with single strand jacks.

Steel Protective Frame

A sturdy steel frame is available to provide protection for the pump unit. It facilitates movement of the pump and offers a useful work surface.

Cleaning Brushes
A range of brushes are available for cleaning wedges and barrels. They can be fitted to any hand-held electric drill motor. The barrel brushes are specially tapered to effectively clean inside of the barrel.

Replacement Parts
Dayton Superior recommends that the user carries a small stock of replacement parts to maintain equipment in good working order. This will help avoid down time in prestressing operations. Approved spares kits are available. Users are encouraged to purchase a spares kit with original equipment orders.

Safety Note: CCL Stressing Systems prestressing equipment is designed with great attention to safety. Always refer to full safety information and operation manuals supplied with the equipment. CCL stressing Systems jacks and pumps form a prestressing system. Dayton Superior recommends that CCL Stressing System chucks and anchors be used with a CCL Stressing Systems jack with power lock-off and load measuring equipment. Use only CCL Stressing Systems chucks, do not mix chucks or chuck parts with those of another manufacturer.

Warning Light
An amber warning light that flashes throughout the prestressing and retracting operations is available and can be magnetically attached to the pump unit or prestressing bed.

See Safety and Maintenance information on page 26.

Release Agent
The proper lubrication of jack wedges is essential. A graphite release agent designed for maximum lubrication is available for this purpose.

4-09

CCL Stressing Systems

Safety Manual For Maintenance and Use of CCL Pretensioning Grips

Important! Read Thoroughly Before Use
CCL Stressing Systems for Concrete Construction

Remember, large potentially lethal forces are being used. These forces can kill. It is vital that to contain these forces, proper procedures for the use and maintenance of CCL grips are followed. Before use, the barrel and wedge should be thoroughly cleaned by either degreasing or using cleaning brushes and lubricated with high pressure lubricant (CCL Super Dippy) before every reuse (See Note 1). Both should be fully inspected prior to being placed in service. If the wedges are fitted with O rings/circlips these should be in place to help prevent stepping (one segment not in line with the others).

1) The use and maintenance of CCL grips General

2) Thread the wedge over the wire or strand and into the rear of the barrel. 3) Tap the wedge lightly into the barrel. A piece of tube is useful for this ensuring the segments do not become stepped. Type B & C Spring-Loaded Grips (SLAs) Spring-loaded grips should always be used at the non-stressing end of the bed. They should also be used at stressing end where jacks without power lock-off are being used. 1) Thread the SLA assembly over the cleaned end of the wire or strand and push up against the bearing surface. It is essential that the front face of the barrel sits fully on the bearing surface and that there are no obstructions on the bearing surface preventing this. Type D & E Double-Ended Joints (DEJs) Double-ended joints/joint reducers are used to connect wire or strand together mid span. Where a reducing joint is used, the prestressing force should never exceed 80% of the manufacturers specified minimum breading load for the smallest wire or strand being used. It is absolutely essential that the double-ended joint is correctly assembled. Ensure that the DEJ screwed barrels are fully threaded onto the center plug. Under no circumstances should a Double Ended Joint be used if either the screwed barrel or center plug threads are damaged and the DEJ can not be correctly assembled. Insert the cleaned end of each wire or strand into the DEJ and push as far as it will go. On strand DEJs, slight resistance will be felt as the safety peg is pushed through the wedge.

Safety
Never fit CCL wedges in other suppliers barrels. Never fit other suppliers wedges in CCL barrels. Never mix CCL wedge segments with those of other suppliers. In the general interests of safety, grips holding wires or strands under load should be shrouded with shrouds of adequate strength to prevent injury or damage in the event of wire or strand failure. The non-jacking end should be shrouded immediately before stressing. The Jacking end should be shrouded immediately after stressing. Double ended joints should be shrouded immediately before stressing and whilst under load stressing should be carried out in a sequence to ensure that the jack operator never stands behind a stressed or un-shrouded wire or strand during stressing. Operators should not stand in line with any stressed wires or strands or stand directly behind the jack. Never walk on stressed strands. Protect open beds with chains or other substantial and suitably constructed guards to protect persons from injury due to sudden wire or strand release. Under no circumstances should a direct hammer blow with a metal-headed hammer be made on the barrel. This could cause a burst or split. Any load/ elongation remaining in the wire/strand must be removed in a controlled manner prior to cutting or burning the wire/strand to remove the grips. Consult Dayton Superior before attempting any prestressing or load/elongation removal procedure that will or may affect the performance of the grips.

(5) Releasing the Grip After Use

In the unlikely event that the wire or strand cannot be pulled out of the grip, insert a grip release tool into the nose of the grip and squeeze together firmly. If it still proves difficult to release the grip, remove it from the stressing area, and providing there is enough wire or strand projecting from the rear of the grip, place a stressing jack onto the wire or strand and pull it out, complete with the wedge. Do not exceed 80% of the manufacturers certified minimum breaking load when using a stressing jack for this operation. If there is insufficient wire or strand projecting, cut the wire or strand about 6mm from the nose end of the grip and using a grip release tool and tube, deliver a sharp blow with a hammer to release. If the hammer blow is still insufficient to release the wedge, a press should be used to push the wedge free of the barrel. Under no circumstances should a direct hammer blow with a metal-headed hammer be made on the barrel. This could cause the barrel to burst or split when used again. Release should be by a blow from a soft material such as wood/plastic, or a hide hammer.

2) Use and maintenance

There are 5 basic types of grip A) Open Grip B) Spring Loaded Grip (Screwed Cap) C) Spring Loaded Grip (Bayonet Cap) D) Double Ended Joint E) Double Ended Joint (Reducer)

(6) Warning

(7) Barrel Maintenance

Terminology Wedge Barrel

A complete wedge comprises 2/3 segments and a retaining o ring.

3) Preparing a grip for use

1) Dismantle the grip 2) Thoroughly clean and degrease all parts paying particular attention to the taper surfaces and the wedge teeth 3) Apply a suitable release agent to the wedge before use (See Note 1). Dayton Superior recommends Super Dippy applied to the wedge and allowed to dry before use. 4) (DEJs only) Refit safety peg midway along the wedges. 5) Reassemble the grip ensuring that the wedge o ring and (where fitted) the spring and spring cap are correctly placed.

1. The taper bore of the barrel must be clean and free from rust and concrete debris 2. Dayton Superior recommends the use of special tapered cleaning brushes to clean the internal taper. Only brushes supplied by Dayton Superior should be used, as other types may cause damage. 3. Do not release grips by hammering. Under no circumstances should a direct hammer blow with a metal-headed hammer be made on the barrel. This could cause a burst or split when used again. Correct lubrication (CCL Super Dippy) will always enable the release of grips. 4. If the barrel becomes deformed at the back, distortion of the taper bore can occur and prevent correct seating on the wedges. 5. Badly deformed barrels should be discarded. Consult Dayton Superior Technical Services if in any doubt. 6. Barrels have a limited service life and visual inspection should be carried out on a regular basis. It is the end users responsibility to discard any barrels that are badly worn, indented by hammer blows or damaged in any other way.

(8) Wedge Maintenance

Fitting The Grip General

1. The wire or strand must be cut square and ragged edges removed 2. In the case of strand ensure that the lay is maintained 3. Dirt and rust should be removed from the wire or strand where the grips are to be placed

(4) Type of Grips

Type A Open Grip Open grips should only be used at the stressing end of the bed with a hydraulic jack incorporating power lock-off. If power lock-off is not available then spring-loaded grips should be used. 1) Thread the barrel over the cleaned end of the wire or strand and push up against the bearing surface.

When not in use, wedges should be lubricated to prevent rusting. Before each use: 1) Clean Care should be take to clean all rust, dirt and concrete debris from the external taper and the internal teeth. Only if the internal teeth are clear to a maximum depth will good usage and safety be obtained. 2) Brush Dayton Superior recommends the use of brass (not steel) wire cleaning brushes to clean the wedge teeth. 3) Visually inspect for chipping Some chipping of the teeth may eventually take place. If more than 20% of the teeth appear chipped, discard that segment. 4) Visually inspect for cracking Some longitudinal cracking could occur, and will vary in intensity depending on the exact diameter of the strand being used. Discard the segment if the cracking becomes excessive. (See Note 2) Note 1: A suitable release agent allows the wedge to be removed from the barrel after use using a minimum of force. Under no circumstances should a direct hammer blow with a metal-headed hammer be made on the barrel. Note 2: Hairline cracks are acceptable but if there is evidence of the crack opening then the wedge must be discarded.

26

4-09

Safety Information

Improper Use of Concrete Accessories Can Cause Severe Injury or Death

Read, understand and follow the information and instructions in this publication before using any of the Dayton Superior concrete accessories displayed herein. When in doubt about the proper use or installation of any Dayton Superior concrete accessory, immediately contact the nearest Dayton Superior Service Center or Technical Service Department for clarification. See back cover for your nearest location.

Dayton Superior products are intended for use by trained, qualified and experienced workmen only. Misuse or lack of supervision and/or inspection can contribute to serious accidents or deaths. Any application other than those shown in this publication should be carefully tested before use. The user of Dayton Superior products must evaluate the product application, determine the safe working load and control all field conditions to prevent applications of loads in excess of a products safe working load. Safety factors shown in this publication are approximate minimum values. The data used to develop safe working loads for products displayed in this publication are a combination of actual testing and/or other industry sources. Recommended safe working loads given for the products in this publication must never be exceeded.

For safety, concrete accessories must be properly used and maintained. Concrete accessories shown in this publication may be subject to wear, overloading, corrosion, deformation, intentional alteration and other factors that may affect the devices performance. All reusable accessories must be inspected regularly by the user to determine if they may be used at the rated safe working load or should be removed from service. The frequency of inspections depends upon factors such as (but not limited to) the amount of use, period of service and environment. It is the responsibility of the user to schedule accessory hardware inspections for wear and remove the hardware from service when wear is noted.

Worn Working Parts

Shop or Field Modification

Welding can compromise a products safe working load value and cause hazardous situations. Knowledge of materials, heat treating and welding procedures is necessary for proper welding. Consult a local welding supply dealer for assistance in determining required welding procedures. Since Dayton Superior cannot control workmanship or conditions in which modifications are done, Dayton Superior cannot be responsible for any product altered in the field.

Interchangeability
Many concrete accessory products that Dayton Superior manufactures are designed as part of a system. Dayton Superior strongly discourages efforts to interchange products supplied by other manufacturers with components supplied by Dayton Superior. When used properly, and in accordance with published instructions, Dayton Superior products have proven to be among the best designed and safest in the industry. Used improperly or with incompatible components supplied by other manufacturers, Dayton Superior products or systems may be rendered unsafe.

Design Changes
Dayton Superior reserves the right to change product designs, rated loads and product dimensions at any time without prior notice.
Note: See Safety Notes and Safety Factor Information on Pages 3 & 4

4-09

27

We have the most complete dealer network in North America. For the dealer nearest your project, simply call the office in your region.

GREAT PLAINS DISTRICT Kansas City 4226 Kansas Avenue Kansas City, KS 66106 1-877-416-3439

ELK GROVE VILLAGE

DAy To N SUpER I o R co R p o R AT I o N 7 7 7 7 WA S H I N G T o N v I L L A G E D R I v E , S U I T E 13 0 DAy To N , o H 45 459 pH o N E: 937- 428.636 0 To L L FR EE co R p o R AT E: 877- 632.9866 T o L L F R E E c U S T o M E R S E R v I c E : 8 8 8 - 9 7 7. 9 6 0 0 To L L FR EE T Ec H N Ic A L SERv Ic E: 877-266.7732 FA x : 937- 428.956 0 DAy To NSUpER I o R .co M

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