Concrete Repair Posts

Injection Ports for Concrete Crack Repair

Posted by John Bors on Fri, Jun 8, 2012 @ 16:06 PM

 

Do you always consider alternative porting methods as you prepare to execute an epoxy crack injection repair project? 

Maybe not. Yet the method selected by your field technician may make a significant difference in the quality, linear footage productivity and job profitability. Many crack injection specifications intentionally leave this option to the practical experience and judgment of the concrete repair contractor.

With a goal of filling a crack with epoxy quickly, neatly, and completely, several factors to consider are:

 surface_port_epoxy_crack_injection

  • Crack width and substrate thickness
  • Application temperature and moisture
  • Orientation (ceiling, wall or floor)
  • Gross linear footage
  • Access limitations
  • Surface appearance after repair
  • Average time duration on port
  • Choice of surface seal material (epoxy vs other)

 Many of our concrete restoration contractors use a combination of several porting methods:

     Taped surface ports 

Stripseal-removable-seal-for-epoxy-injectionLow cost ports are established as gaps in the surface seal with quarter inch masking tape applied at the proper interval prior to the surface seal. The tape is pulled before the seal hardens completely. With hand pressure, the injection mix head directly contacts the open gaps left by the tape though a compressible rubber grommet or rubber tip such as our part # B07 which is available in two sizes (see last image below). After the port is filled, soap or wax is manually rubbed over the crack to seal the port. Some of the long time specialty concrete repair contractors insist that this method is the most efficient practice for most crack injection projects. This method is illustrated in the top image for use on an industrial floor and in the second image (to the left) in conjunction with our peelable surface seal StripSEAL.

     Rubber tips, pins, wire, (finishing) nails, straws, golf tees and toothpicks 

These alternatives to tape often require no drilling. Sometimes they are used in combination. For example, rubber tips (such are our part # B07-3 or B07-12) can be located along the crack with toothpicks, (or pins or nails) prior to the seal application. To inject, the toothpicks are withdrawn and the mix head nozzle is inserted into the tip. Conical shaped golf tees work better than standard tees (because of their thicker shaft) but are hard to find.

     Surface ports  plastic-injection-surface-ports-for-crack-injection

Injection molded of PE plastic or nylon, surface ports for crack injection have become very popular in the last 10 years. These consist of a flat base flange perpendicular to a small diameter tube for easy connection to the injection equipment using a 1/8” NPT press-to-fit connection. Although more costly from a disposable parts cost standpoint, field technicians appreciate the benefit of not having to manually hold the injection head against the port, particularly on ceilings or when time on port will be high.

     Packers, Zerk fittings and grease fittings

These port options for epoxy injection are popular when high pressures are used and are standards for use with chemical grouting, a term usually affiliated with polyurethane (PU) injection. PU is a material option for waterproofing and leakproofing but is not considered for structural repairs. Almost always these types of port connections are a most expensive cost option and are used with a drilled hole (see below). These connectors are often self-sealing with a spring loaded ball so the field technician doesn’t have to worry about material leaking from an uncapped port.

     Drilled Injection Ports

Port connections for drilled holes can be made by the contractor at low cost by cutting sections from 1/4 or 3/8” polypropylene supply hose (same as used for the water supply line for an icemaker), purchased as pre-molded units or supplied as a tapered Semko® tip. This method is one of the first choices when injection flows are obstructed by the type of crack, surface obstructions, plugging, or  for accessing voids under a sound surface (such as a de-bonded topping slab). If the crack is narrow, a water-flushed core bit is far superior to an impact bit as it is less likely to pack the crack around the hole with drill fines (leading to more obstruction).

rubber-tips-for-surface-port-epoxy-injection

Tags: plastic crack injection ports, concrete crack repair epoxy, concrete restoration epoxy

Why your concrete repair epoxy is out of stock

Posted by John Bors on Fri, Jun 1, 2012 @ 18:06 PM

 

To our industry friends,structural epoxy mortar

On behalf of ChemCo Systems, we hope that your summer is off to a great start!

We are hearing a number of sad stories from concrete repair contractors across North America. They are telling us that getting epoxy and other concrete adhesives, restoration and repair materials on a timely basis has been a frustrating challenge especially this year.

Why are manufacturers and distributors keeping such small inventories? What is taking so long to fill back orders? 

The answer is that the construction chemical business (which includes epoxy adhesives, bonders, grouts and coatings for concrete repair, maintenance and restoration) is notorious for being impossible to forecast. So the manufacturers of the finished polymer based products don’t know how much raw material to inventory especially since the economy has been in the doldrums for so long. Nor can the manufacturers can’t rely on previous year’s results to help with estimating their needs. Another issue has been that the raw material producers have reduced their inventories and discontinued some very useful specialty additives that are hard to replace in formulations (with little or no notice). Finally, because pricing battles between major brand names for the few large orders have reduced profit margins, the corporate bosses have mandated lower inventory levels.

The net result is that even popular epoxy concrete restoration products are frequently out of stock and sometimes unavailable for a month or longer. 

One contractor recently needed to precisely schedule delivery of materials because his customer was setting a narrow time window for a manufacturing shutdown for a concrete resoration project to repair surfaces in some material storage bins. So he contacted the specified product’s manufacturer a month in advance to place his order for two epoxy repair bonders. With less than a week to go, he recontacted the manufacturer to learn that his material had not been made and would not be available for another month. At the last minute, he called ChemCo to see if we could help.

We were able to schedule, package and ship his order in 2 days.

We can act fast because we don’t report to any big bosses. And in the last year we have increased our raw material inventory levels so we can respond to contractors in last minute panic situations including Friday afternoon at 3 pm. Please give us a call any time you need epoxies for concrete repair in a hurry. You won't be disappointed!

ChemCo Systems epoxies for concrete repair

Tags: concrete restoration, out of stock epoxy, concrete repair epoxy, concrete restoration epoxy