MC-Bauchemie MC-Centrament Accele 350
A chloride-free accelerating admixture from MC-Bauchemie that pushes early cement hydration so concrete stiffens sooner, gains strength faster and lets formwork come off ahead of schedule.
What is it?
A liquid, chloride-free accelerating admixture (MC-Bauchemie Centrament accelerator family) that shortens the setting time of Portland-cement concrete and mortar and boosts early-age strength.
Where is it used?
Precast yards, cold-weather and winter pours, fast-track slabs, repair mortars and any pour where early formwork stripping or early loading is on the critical path.
Why use it?
It brings forward the strength curve without chloride, so cycle times drop and steel stays protected from corrosion risk.
How is it applied?
Dosed into the mix water or added at the batching plant at the rate confirmed on the current MC-Bauchemie datasheet for your cement, then mixed to a uniform blend before placing.
About MC-Bauchemie MC-Centrament Accele 350
Concreting to a clock is one of the hardest parts of any programme. In a precast bed you want the element ready to demould in a single shift; on a winter site the ambient temperature drags hydration to a crawl and the pour simply refuses to set; on a repair job the traffic has to come back on. MC-Centrament Accele 350 belongs to MC-Bauchemie’s Centrament family of set and hardening accelerators, formulated to attack exactly this bottleneck. It is a chloride-free liquid that works with ordinary Portland cements to shorten the dormant period, so the mix stiffens and starts building strength earlier than an untreated reference batch.
What separates a modern accelerator like this from the old calcium-chloride shortcuts is the chemistry. Chloride accelerates concrete beautifully but leaves free chloride ions sitting against the reinforcement, and over years that is a direct driver of rebar corrosion and spalling. MC-Bauchemie’s chloride-free formulation delivers the same early-age push using non-chloride reactive components, which is why it is considered safe for reinforced and prestressed work where a chloride admixture would be prohibited outright. For engineers in Delhi NCR and across India, that combination of faster turnaround and durability compliance is the whole point: you accelerate the programme without accelerating the deterioration.
The technical insight
Cement setting is governed by the hydration of two phases in particular, tricalcium silicate (C3S) and tricalcium aluminate (C3A). Freshly mixed concrete sits in a dormant period while these phases slowly start to react; the accelerator’s job is to shorten that dormancy. The reactive components in a chloride-free accelerator raise the rate at which C3S and C3A hydrate, so calcium-silicate-hydrate gel and ettringite form sooner. The practical result is that the mix passes through initial and final set earlier and the 24-hour strength climbs faster than a plain control batch. The effect is most pronounced where hydration is naturally sluggish, i.e. at low temperatures, which is exactly why accelerators earn their keep on cold-weather and winter pours. Because the mechanism speeds up hydration that would have happened anyway rather than adding chloride, a correctly dosed chloride-free accelerator is not expected to compromise the long-term 28-day strength or the durability of the hardened concrete.
Where it is used
- Precast and prestressed element production where a fast demould cycle drives yard output
- Cold-weather and winter concreting, where low ambient temperature otherwise stalls setting
- Fast-track slabs and structures that need early formwork stripping to keep the programme moving
- Concrete and mortar repairs where early strength lets the area be reopened or reloaded sooner
- Early loading of construction joints and successive lifts
- Ready-mixed concrete requiring controlled acceleration of set and early strength
- General reinforced and prestressed concrete where a chloride accelerator is not permitted
Key advantages
- Chloride-free, so it is safe for reinforced and prestressed concrete without the corrosion risk of calcium-chloride accelerators
- Shortens initial and final setting times, bringing early strength forward and shortening cycle times
- Restores workable hydration on cold-weather pours where setting would otherwise stall
- Speeds precast demoulding and formwork stripping, directly improving productivity and formwork turnover
- Liquid form disperses cleanly in the mix water for uniform, repeatable batching
- Correctly dosed, it accelerates early age without sacrificing long-term 28-day strength
- Backed by MC-Bauchemie’s global admixture technology and supplied with full technical support through Space Arc
Limitations & considerations
- Not a frost-proofing agent: it speeds hydration but does not replace proper cold-weather protection, insulation or heating below freezing
- Overdosing can cause rapid, uncontrolled stiffening and reduced workability, so trial mixes are essential
- Acceleration and dosage response vary with cement type, temperature and mix design, so plant calibration is needed for each mix
- Exact dosage, current grade designation and standards classification must be confirmed against the latest MC-Bauchemie technical datasheet before use
- As an accelerator it shortens working time; placing, compacting and finishing must be planned to keep pace
- Compatibility with other admixtures in the mix should be verified before combining
Selection & best practice
Always start from the current MC-Bauchemie technical datasheet for the exact grade and dose it by mass or volume of cement within the stated range, never by guesswork. Add the accelerator to the mix water or introduce it at the batching plant, and mix thoroughly so it is uniformly distributed before discharge. Run trial batches with your actual cement and aggregates at the temperature you expect on site, and record set times and early strengths so the plant is calibrated for the real conditions rather than a lab ideal. Because acceleration shortens the working window, have placing, compaction and finishing crews ready before the concrete arrives, and reduce haul and standing time. On genuinely cold pours, treat the accelerator as one part of a cold-weather regime alongside protection and, where needed, heating; it speeds the reaction but is not a substitute for keeping the concrete above the required temperature. Keep the product from freezing in storage and stir before use if the datasheet calls for it.
Specifications
| Product family | MC-Bauchemie Centrament accelerating admixture range |
| Function | Set and hardening accelerator for concrete and cement mortar |
| Base chemistry | Chloride-free, non-chloride reactive accelerating components |
| Form | Liquid admixture, dosed into mix water / at the batching plant |
| Chloride content | Chloride-free (safe for reinforced and prestressed concrete) |
| Suitable cements | Ordinary Portland cements |
| Effect on 28-day strength | No adverse effect when correctly dosed |
| Dosage | Per current MC-Bauchemie technical datasheet for the specific grade — confirm before use |
Industry use cases
Precast Concrete Manufacturing
Yards use the accelerator to reach demould strength within a single shift, freeing beds and moulds faster and lifting daily element output.
Winter and Cold-Region Construction
On low-temperature pours the admixture restores a workable rate of set so hydration does not stall, keeping the programme on track through cold months.
Infrastructure and Repair
Bridge deck patches, industrial floor repairs and joint work gain early strength so lanes, bays or plant can be reopened and reloaded sooner.
Fast-Track Building Works
On tight-cycle structural frames it allows earlier formwork stripping between lifts, compressing the floor-to-floor cycle without chloride risk to the reinforcement.
Frequently asked questions
Is MC-Centrament Accele 350 chloride-free and safe for reinforced concrete?
How much does it accelerate the set?
What dosage should I use?
Will it reduce my long-term strength?
Can I use it as antifreeze in sub-zero concreting?
Can Space Arc supply this across Delhi NCR and pan-India with technical support?
How we position MC-Bauchemie MC-Centrament Accele 350
Choose MC-Centrament Accele 350 when you want an MC-Bauchemie chloride-free accelerator to bring the strength curve forward on precast, cold-weather or fast-track work. Within MC-Bauchemie’s own admixture family it pairs naturally with a Centrament-range water reducer or superplasticiser when you need flow as well as early strength, and it sits opposite Centrament Retard 350, MC-Bauchemie’s set retarder, which is what you reach for when the requirement is to slow the set for long hauls or hot-weather placing. Across our other brands, the closest and most widely specified equivalent is Fosroc Conplast NC, a chloride-free accelerating admixture our engineers often recommend where a project is standardised on the Fosroc system. Our team can help you match the right accelerator, retarder or plasticiser to the actual pour rather than defaulting to a single product.
Fosroc Conplast NC — Specify the Fosroc option when the project is standardised on the Fosroc admixture system or the spec calls for BS 5075 Part 1 and ASTM C494 Type C compliance, as Conplast NC is a directly equivalent chloride-free accelerating admixture.
Related Concrete Admixtures products
Source MC-Bauchemie MC-Centrament Accele 350 for your project
Authorised distribution, technical advice & professional application across Delhi NCR and Pan-India.