Concrete Pole Mold Operation Attention

Attentions During Concrete Pole Production

The Centrifugal Spinning Machine For Concrete Pole Should Match Concrete Pole Mould 

 1. The steel of riding wheel and running wheel should match.

The spinning friction of riding wheel of centrifugal spinning machine revolves the running wheel of concrete spun pole steel mould, so the steel of both should match. Therefore, the rigidity of both should be confirmed before the order of the equipments. The supplement or update of the centrifuge machine should also pay attention to the match and it should be recorded in machine archives for the future reference.
 2. Match of the Angle between Concrete Pole Mould and Centrifugal Spinning Machine
The angle should not be too big or two little. More smaller, more shaking of the pole mould, namely the more revolving force , the more shaking of the mould . So, the angle should be

  Overhang  of both ends of pole mould should be avoided or length of overhang should be shortened

 The distance of riding wheel of centrifugals spinning machine for concrete spun electric poles usually is 2m.If the number of length of the pole mould is odd number(7,9,11m), the length of hangover of both end outside the machine is 0.5m; if the number of length is even number(6,8,12m),the length of hangover is 1m. The deflection of the hangover is in proportion to the length of hangover. Longer, the deflection is bigger and the shaking will be more obvious when spinning which will not only affects the density of concrete but also speed up the deformation, damage. To this, below measures shall be taken:
 1.when the centrifuge machine with the length of wheel distance 2m is used and the number of length of the product finished is odd number, the length of hangover of the concrete pole mould shall be controlled within 0.5m; if the number is even number, no length of hangover, namely the ends of mould are running wheels.
2. The distance of riding wheel of centrifugal spinning machine is still 2m, but if the distance of one end is changed into 1.5m and the length is even number, and the distance of running wheels of one end is also changed into 1.5m, and the length of hangover is only 0.25m; when the production length is uneven number, without 1.5m riding wheels, the length of hangover of steel mould should keep 0.5m.

 2.The deformation of concrete spun pole mould should be avoided from the improper operation

 1. The bearing platform of concrete pole mould should be at the same level.
The bearing platform of concrete pole mould means the platform bearing the concrete pole mould when operated, such as the pouring platform, link bolt platform. If the bearing platform is not flat, the wavy deformation will happen to the mould. When the bolt is fastened, the bent shape will be kept for the mould on the bearing platform.
2. The prestressed steel should be tensioned as a whole part.
3. If tensioned with single steel, every prestressed controlling value is difficult of keep same, meanwhile, the pressures born by the mould will not be consistent. The pole mould will deform when it’s worst.
3. The method of twisting the link bolts should be noted.
There are two factors of reasonable procedure for twisting link bolts. One is two sides are symmetrically operated at the same time. If one side is twisted first, then another side, then the latter one is difficult to screw up. The bolt is easy to loosen. Another is twisting from big end to small end or conversely or from the middle to the two sides.
4. Reasonable fulcrum of hanging the mould
 During production, the hoist of pole mould is usually accepted that keeping the mould horizontal by controlling the mould is ok. Actually, the flat should be the one with the guarantee of the deflection of hangover and deflection of midspan match which will usually be neglected. When confirming the location of the hanging rings of moulds, the span of hangover of mould should be equally to the bending moment of mid span. When using the steel mould whose prestress is generated by the tension with the small end anchoring the big end, the anchoring plate should be in the same position with the tensioning plate. One hanging point will be set 0.21L from the small end, and then attempt to lift the big end of the mould with steel wire rope to move to keep the mould horizontal. The mould will bend and deform after a long period of use if the flat is not on the base of equal bending moment, fitting deflection.

3. Pay much attention to link bolt 
 1. the link bolt needs improving.
The current link of mould is shown as the drawing (a). Considered in theory, the tongue and groove plate is welded closely, so the rigidity is just ok for the hoist of mould but compared to the bearing the prestressed pressure, no better than the flush plate and tongue and grooved board. There is shortage in the use of current link: one is the welding seam of link is so easy to crack that the whole link will come off; the second is the less bearing surface for the link will be worn and incline outward which resulting to the loosening of the bolt when centrifugal spinning; the third is difficult closing of the link of running wheels and the ones of the seam-closed of mould. If changed to the one as per the drawing (b), changing the close weld of the tongue and groove board to flush board, will have two advantages except overcoming the above shortages： one is the seam-closed will be more tight; another is simple manufacturing.






2. Complete the link bolts


 The shortage of link bolt will cause the space when closing the mould thus resulting to the paste-leaking. If the shortage occurs near the running wheels, the diameter of the running wheel will be expanded when spinning leading to the deformation and running out of mould. Meanwhile, there will be a impact to the riding wheel of centrifugal spinning with the frequency of 800~1000rpm when the spinning speed is 400~500rpm from the seam of running wheel.
Some people think , some vibration is allowed in the moulding of the products. Yes, that is necessary for the compactness process the initial moulding. But the later vibration will cause the compacted products cracked seam, isolation which will do harm to the products. Moreover, the impact of mould to the centrifuge machine will cause the vicious circle of damage of pole steel mould and centrifugal spinning machine.

 Production of shorter poles with longer moulds is not recommended
With no-load on one end of mould, producing the shorter poles with longer moulds will cause the run out surely. The run out will mainly cause the deforming and damage of the mould besides affecting the density.

 keep exterior clean of steel mould
During the production, the eccentric force caused by piled on residual slurry is often neglected. For example, when the work is done, some factories won’t clear away the residual slurry in the mould and when mould is hoisted away from the centrifugal spinning machine ,the residual slurry will flow outward. The accumulation of days and days will increase the attached weight of mould and then the eccentricity run out will be caused when spinning which will exacerbate the shaking of the hangover the mould which will not only affect the quality but also damage the mould easily.

  Strengthen the maintenance of centrifugal spinning machine
The centrifugal spinning machine for concrete spun pole mould and the steel pole mould interact on each other. So, if to protect the mould, the maintenance of the centrifuge machine must be strengthened. When put into normal production, there will be a specially-assigned worker for the maintenance. When holiday of the factory, concentrate more efforts on the examination, correct the deviation, eliminate the hidden danger and keep the centrifuge in good condition all the time.

Concrete Pipe Making Process of Suspension Roller Type and Quality Control

1 Overview

The current concrete pipe mainly includes prestressed concrete pipe, concrete pipe and reinforced concrete pipe. The reinforced concrete pipe is mainly used in highways and the pipe making method mainly includes centrifugal, suspension roller type, vertical extrusion and vertical vibration. Compared with other pipe making process it has the advantages of high strength of pipe external pressure, heavy external load, no leaking, high compactness, good permeability, long durability.

concrete pipe machine

2 Pipe Forming Process

The suspension roller type pipe making process utilize the suspension roller driven by the motor drive the mould with the friction of roller and concrete pipe mould. And then with the centrifuge produced by the mould revolving, the concrete mixer will adhere to the inner wall of mould evenly. With the increase of material, the pipe wall will get thicker. When the concrete thickness excesses beyond the mouth of pipe, the mouth will leave the suspension roller. At this moment, the concrete in the pipe inner wall with contact with revolving roller directly. The mould revolves relying on the friction. Meanwhile, the overhang roller will roll press repeatedly. With the increase of thickness of concrete, the pressure on the pipe wall is heavier, the less time will take to compact the concrete and form the smooth surface.

3 The features of pipe making with suspension roller method

3.1 Stiff concrete, compacted pipe wall, the pipe body can bear higher load.

3.2 The feeding time is short, as well as molding time, the production efficiency is high.

3.3 The waste of concrete is less, no waste cement slurry, no pollution.

3.4 The intensity of high frequency produced during pipe forming process is lower.

3.5 The operative technique is difficult and if can't controlled appropriately the problems such as anti-permeability is not good, the pipe body is not smooth, the pipe wall is quite thick and the slump of pipe wall.

4 Quality Control

4.1 Raw Materials

Cement: the cement should conform to the national standard, and the cement strength grade should not be less than the concrete pipe design strength grade.

Reinforcing bar: the quality of bar should meet the national standard. The bars should be examined by batch when entering the workyard.

Ballast: the quality of ballast should meet the standard of nation. The content of needle shape ballast no more than 15%, the sand content no more than 1%, clay lump content no more than 0.5%, maximum size of ballast no more than 1/3 thickness of pipe wall as well as 3/4 clear distance of circumferential reinforcing bar.

Sand: the quality of sand should accord with national standard. The silt content should not be more than 3%. If the concrete pipes are made of sea sand, the chlorine salt content can't be more 0.1%. when entering the workyard they should be examined by batch.

Additive: the quality of additive should conform to the national standard. The concrete pipes should not be mixed with concrete additive which have corrosive effect on reinforcing bars.

4.2 Mix Ratio

The mixture ratio is the important factor affecting the concrete strength. the concrete used in concrete pipes with hanging roller method is different from general concrete. With the method of suspension roller making pipes, the harsh concrete is necessary. Water cement ratio is generally controlled in 0.3~0.36 or so. Vebe Consistometer is controlled in 20~50s or so. More specific mix ratio differs according to requirements of design strength of concrete pipe. So, it should be confirmed in test room with test mix.

4.3 concrete pipe mould

The mould is an important factor affecting the appearance of concrete pipe. The dimension of every part of the mould is in allowable range, there is no obvious gap in the both ends and joints; the connection of all parts should be tight and reliable. The mould should be made from the steel plate with certain rigidity. The dimension allowance meets the quality requirement; the whole rigidity can meet the construction requirements. The inner surface is clean, no rust.

Technical Requirement of Concrete Pole Mould of CICQ Industry

1 Basic Requirement

1.1 The concrete pole mould should meet the standard requirement and be made according to the drawing authorized by regulatory procedure and technical documents.

1.2 The safety and sanitary requirements of design and manufacture of products should conform to GB 5083.

1.3 The general tolerance of linear dimension of drawing should conform to M Level of GB/T 1804-1992 in machining working parts; and the non-machining parts should conform to C level of GB/T 1804-1992.

2 Requirements of Main Parts

2.1 segmented moulds

2.1.1 Deviation of space of adjacent two running wheels is ±1mm.

2.1.2 The perpendicularity connecting surface of flange with cylinder center line tolerance is 0.25mm.

2.1.3 A seam no more than 0.5mm is allowed on the parting surface of tongued and grooved board; the seam more than 0.5mm and less than 1mm is on half mould. The single segment length should be not more than 100mmm. the accumulated length should not be more than 1/10 of segmented mould; seam more than 1mm is not allowed.

2.1.4 The grade of tolerance of diameter of supporting board and holder mouth of connecting flange is IT9. The maximum allowable value of surface roughness R is 6.3µm.

2.1.5 The defects such as crack, hard spot, delamination, scars and rusting are not allowed on the inner surface of moulds.

2.1.6 When process with riveting, a hole no more than 1mm is allowed around the rivet of inner wall of moulds, however should be rounding off.

2.2 Running Wheel

2.2.1 The tolerance grade of diameter of working surface is IT9 and the maximum allowance value of surface roughness R is 12.5um.

2.2.2 The grade of tolerance of inner diameter supporting positioning is IT9. The maximum allowance value of surface roughness R is 6.3µm.

3 Requirements of Materials

3.1 The materials should conform to the regulations of GB/T699 and GB/T700. The mechanical performance of moulds, tongued and grooved board, ribbed slab, flange materials should not go lower than the requirements of Q235-A; the mechanical performance of bolt should not be lower than than 8.8 grade of GB/T 3098.1-1982, the mechanical performance of nut materials should not be lower than 8 grade of GB/T3098.2-1982.

3.2 The steel casting should conform to the regulations of JC/T 401.2-JC/T 401.4. And mechanical performance of running wheel materials should not be lower than requirements of ZG270-500 of JC/T 401.2-199.

4 Welding Requirements

4.1 The welding should conform to the regulations of JC532. And the surface quality of welded joint between running wheel and holding flange, connecting flange and end flange and moulds should not be lower than Ⅲ grade of JC 532-1994.

4.2 Assemble RequirementsThe weld-seam on the inner surface of mould should be finished and maximum allowable value of grinding surface roughness is 25µm.

5 Assembling Requirements

5.1 The dimension limit deviation of inner diameter of mould is +2, -1mm; the dimension deviation of inner diameter of parting surface is +4, -2mm and should be rounding off.

5.2 The deviation of tessellation line straightness of inner surface of mould in the full length range is L/2500 but should be no more than 5mm.

5.3 The length deviation of mould should not be more than 0.5%.

5.4 Joint gap of inner surface is no more than 0.25mm; the circular gap of connecting the inner surface of flange is no more than 0.25mm.

5.5 The joint displacement of inner surface is no more than 1mm; inner surface of connecting flange is no more than1mm and should be grinded smooth. The grinding inclination is no more than 1/100, the matched displacement of connecting flange is no more than 1mm.

5.6 The distance of running wheel is 2m and the deviation should not be more than 2mm; any tread of two running wheels is integral multiple of 2m. And deviation is not more than 4mm.

5.7 The axiality tolerance of running wheel and mould Φ is 2mm.

5.8 After the link bolt is fastened, the nut should come out of bolt, but the emerging length is not more than 15mm.

6 Appearance Quality

6.1 there should not be burr, sharp edge, welding slag and bruise such defects.

6.2 the placement of longitudinal and circumferential slabbed plate should be straight and flat.

6.3 After the linked bolt is fastened, the external side of link lock should not incline toward the parting surface.

6.4 the painting requirement should conform to the regulations of JC/T402.

7 Requirements of Test Run

7.1 Non-load running of mould should be steady and no abnormal noise.

7.2 Loaded running of mould should be steady and no abnormal noise. And there will no be paste leaking occurring on the joints and flange connection when running with loaded.

Principle and Manufacturing Technology of Concrete Spun Pole Moulds

Two centrifugal methods manufacturing circumferential concrete poles with centrifugal spinning machines in domestic: centrifugal method of lathe type and friction roller drive. The former only make non-prestressed concrete poles and the latter can make various circumferential concrete poles such as non-prestressed concrete poles, prestressed poles, partial prestressed concrete poles and steel cylinder concrete poles.

The article only briefly introduces manufacturing, installation, maintenance and repair of concrete poles manufacturing circumferential prestressed concrete poles with friction roller method. To make circumferential prestressed concrete poles on the concrete pole spinning machines with different kinds and different length, it's essential to learn the national standard of circumferential prestressed concrete poles. The standard stipulates 19 kinds of poles and 60 specifications. The length of whole pole is 6m of short poles; the longest poles is 15m. According to the national standard (JC/T364-2001), the wheel distance of running wheel is 2m. If the whole circumferential prestressed concrete pole with 15m is produced on the centrifugal spinning machine, then 8 running wheels which are supported on the roller will be necessary. In design of steel moulds there are two structure types: one is half-opening type; another is all-opening type. The notch is existed only in one side of half-opening mold. The feature of this kind mould is no paste-leaking; the good coaxiality of concrete electric pole steel moulds; the low requirements of centrifugal spinning machines. The disadvantages are the waxing top-pushing technique during the processing of poles, so the surface of poles is not enough smooth and also one complete set of equipments of wax irrigation and wax recycle and one set of top-pushing equipments and concrete injection pump. All these cause a great investment cost. Therefore, this is not applicable to most of concrete products factories. Another is whole-opening type. The  two half are positioned with chase mortises and then integrate molds with bolts on the parting surfaces. This type is widely used by most of concrete factories. The structure of this type is as shown in picture 11-3-1.

During manufacturing the half moulds, the steel plate of 8mm is usually used in the cylinder body. As the taper ratio of taper poles in the national standard is 1:75. So the cylinder plate will be processed in the special conical mould with cold pressure.As the limitation of width of steel plate shearer, and limitation of length heat of cold pressure mould , equipments of cold working, in generally, the factory will design the pipe wall plate length 2m, and then connect with segments. In addition, as the limitation of manufacturing range of machining equipments and restriction on delivery vehicles and roads, so the length is designed among 4m, and some special will be among 5m. To ensure the steady and high-speed run and non-deformation, the supporting plate and lining board will be welded on the cylinder; the reinforcing plate should be welded on the slot-coupling, the connect flange in the segmented welding joint. The reliability of of cylinder plate of 8mm can be ensured during high speed running. So the rigidity of longitudinal and horizontal of cylinder surface should be improved. The common practice is to weld the longitudinal and horizontal ribbed plate and weld the end-plate flange which is connected with longitudinal reinforcing plate. How integrate two half moulds? According to standard of JC/T364-2001, two reinforcing plates thicker than cylinder plate will be riveted on the cylinder plate of parting surface.

One is to rigidity of horizontal end and the second is to plane the mortise on the reinforcing plates to merge into whole mould. The reinforcing plate and pipe wall plate is connected with riveting meanwhile, couples of lug bolts can be welded on the reinforcing plate. The crane rings of slinging and rolling moulds can be weled on the reinforcing plates.

Hot Sale Concrete Electric Pole Making Machines

Hot Sale Concrete Electric Pole Making Machines

The mould has the characteristics of high strength, good rigidity and durability etc., and it is an indispensable mould for making pre-stressing steel bar and concrete electric-pole, as well as non-prestressing steel bar and concrete electric-pole.

Centrifugal Spinning Machine of Concrete Electric Pole Making Machines 
With centrifugal forming method, the machine is main equipment for making various annular electric-pole concrete wares with various nominal diameters and lengths, matched with stepless motor and control equipment.

Product standard

Steel mould small end inner diameter(mm)	Length (m)	Wheel Span	Wheel diameter (mm)
130	6-8	2000mm	560
150	8-10	2000mm	600
190	9-15	2000mm	600
230	6-15	2000mm	680
310	6-9	2000mm	680
350	6-15	2000mm	680
390	6-9	2000mm	680
430	6	2000mm	680
470	6	2000	750
510	6	2000	750
550	6	2000	850
Equal diameter 300	6-9	2000	600
Equal diameter 400	6-9	2000	680